Pipelines 2008: Pipeline Asset Management: Maximizing Performance of our Pipeline Infrastructure

South San Joaquin Irrigation District (SSJID) was faced with a reduced demand for irrigation water while the nearby cities were experiencing increased domestic demand and deteriorating ground water supplies. The District made the decision to supply potable water to the local communities. The project, which is now in service, will supply up to 60 mgd of treated water to the communities of Escalon, Manteca, Lathrop, and Tracy located in the Central Valley of California. The drinking water is treated in a new membrane filtration plant located adjacent to SSJID's Woodard Reservoir. The water is delivered through 37 miles of pipe and five turnouts. Each turnout has an at-grade steel reservoir and booster pumps. The pipeline design and construction included, in addition to the pipe, 10 railroad crossings, two interstate crossings, two microtunneled levee crossings, and a 641-foot-long four span pre-engineered steel truss bridge over the San Joaquin River illustrated in Figure 1. During the design and construction of the San Joaquin River Bridge Crossing the following lessons were learned. 1 Maintain a spirit of cooperation with all stakeholders throughout the entire project. 2 Hold the contractor and the bridge supplier to the requirements of the contract while being responsive to their issues and constraints. 3 Be fully aware of all project and permit constraints so that intelligent options exist. 4 Maintain excellent communication and coordination as a designer with the field inspection and resident engineering staff. In this paper the discussion will focus on how these lessons were learned while facing the challenges this bridge crossing presented.

The present paper investigates the structural stability of thin-walled steel cylinders subjected to uniform external pressure. A brief discussion of unconfined steel cylinder buckling is presented first. Subsequently, motivated by the design of buried pipelines, buckling of confined steel cylinders, surrounded by an elastic medium, is examined. A two dimensional model is developed, assuming no variation of load and deformation along the cylinder axis. The cylinder and the surrounding medium are simulated with nonlinear finite elements that account for both geometric and material nonlinearities. The external pressure response of confined thin-walled steel cylinders is examined, in terms of initial the out-of-roundness of the cylinder, the initial gap between the cylinder and the medium, and the stiffness of the surrounding medium. Numerical results show a rapid drop of pressure after reaching the maximum pressure level. Finally, the numerical results show good comparison with a simplified closed-form expression, proposed elsewhere, which could be used for buried pipeline design purposes.

This paper presents an overview of field tests for buried pipe, which were conducted using steel pipes with 3500 mm diameter and 26 mm thickness. In this full-scale test, five kinds of construction site were employed. The depth of soil cover was approximately 3.0 m in every case. Sheet pile method was employed in Case-5, and open-cut method was conducted in the other cases. Displacement transducers were installed in the pipe and strain gauges were circumferentially attached to the inner of the pipe. The deformation of pipe was observed for over a year by those measures. Therefore, it is found that the behavior of the buried pipe was strongly influenced by backfilling methods. In addition, FEM analyses were conducted to confirm the behavior of soil-pipe interaction. Thus, it is found that the inhomogeneous strength of backfill materials brings local deformation of the pipe.

This paper presents concepts that evolved through a research project sponsored by the Pipeline Research Council International (PRCI). The objective of the project was to investigate methods for the reduction of claims for extra compensation associated with horizontally directionally drilled (HDD) pipeline installations in rock. These claims result from HDD contractors' allegations that rock properties experienced during construction are significantly different from the properties on which the contractors' bids were based. The paper provides information and recommendations that improve exploration and testing methods for assessing the drillability of rock to be encountered on HDD pipeline installations. It is anticipated that these improvements will lead to a better understanding of rock drillability which will in turn lead to more accurate bid prices and more effective drilling plans, thereby reducing claims for extra compensation. The paper also addresses contractual and risk management considerations and alternate dispute resolution.

Minimal disruption water main renewal technologies offer opportunities to extend the life of existing infrastructure with less cost and reduced public inconvenience compared to traditional replacement options. These renewal options cover a wide range of applications, but it is important to understand the project requirements to select an appropriate solution. This paper will provide an overview of the information required to determine which technologies can provide the best option for water main renovation. This includes the existing condition of the host pipe, the current operating conditions, and the level of service that the renovated pipe is expected to provide. In the industry, there are a number of terms used to describe liners. They can be called structural or semi-structural, or interactive or independent, depending on the classification system used. This paper reviews the terminologies, and how they correspond to each other. Understanding these concepts is a requirement in liner selection. This paper will also present brief case studies on two projects completed in 2007 in North America. The case studies deal with polyethylene liners ranging from 12 inches to 24 inches in diameter, installed using two different cross-section-modified techniques, providing interactive and independent liners.

Irrigation project of Khorramshahr area should be started to supply people with a new irrigation system to cover more than 10,000 HEC. Economic assessments led to a selection of an easy and financial scheme using international standards and national independence criteria. Therefore, artificial intelligence designing could be used to solve the problem of costly designing and expensive water transmission. Physical model is based on segmental parts and flexible joints. This model considers spinal cords behavior using three degrees of freedom of movement and bending. Joints are designed to absorb the interactions of soil bed and pipeline displacements. Therefore, tentative joints were made and then orders were given to Iranian factories for such a product. In addition, discharging pipeline for mending purposes may lead to section warping. Huge stresses created in practice should be considered by the factory design department. Maximum deflection is computed by physical models when the pipeline is empty or when it is instantly charged. A result of the physical model is that it can produce circular pipeline with a diameter of 500mm to 3000mm.

Subsurface Utility Engineering (SUE) reduces unnecessary utility relocations, unexpected damages of existing utilities, miss-locations of utilities, change orders and claims, personnel injuries, negative factors for productivity, social and environmental damages, and other problems related to utilities through accurate underground information. The benefits are combined with subsequent savings in time and cost for whole projects. Considerable previous research has shown that using SUE can save money on projects involving underground utilities. This paper describes a benefit-cost analysis (BCA) that quantifies the cost savings of SUE with projects developed in Pennsylvania. This study uses both SUE projects and non-SUE projects to quantify the cost savings of SUE on highway projects. This study focuses on a detailed benefit-cost analysis performed on twenty-two SUE projects and eight non-SUE projects.

The City of Newark, NJ is in the midst of a commendable program to preserve its historic brick sewer system. The City's extensive Brick Sewer System Evaluation Program began in 1990. CDM has been the City's consulting engineer since Phase III/IV of the Program, which began in 1997. To date, CDM has overseen the evaluation of more than 149,000 linear feet of combined brick sewers and the structural rehabilitation of approximately 86,500 linear feet with cured-in-place pipe (CIPP). This sewer rehabilitation work has been conducted through seventeen different construction contracts over the past six years. The City and CDM are presently working on Phase VI of the Program which includes the re-evaluation of sewers inspected previously (approximately 124,000 linear feet) and anticipates the rehabilitation of 24,000 linear feet. Throughout the Program, the City has had the goal of making the rehabilitation as complete and long-lasting as possible. With this goal in mind, the Program has included particular attention to details such as intermediate manhole rehabilitation and sealed connection points between laterals and the lined sewer. Other sound practices include frequent communication with affected residents and business owners, isolating work areas to the extent possible, minimizing road closures, and utilizing temporary bypass pumping. These have also been employed to ensure a sound finished product with minimal disruption to the City. Most of the brick sewers rehabilitated have been egg-shaped and all have been greater than 20 inches in size. Various aspects of the construction process have been refined during the course of the Program. These items include procedures for the verification of sewer sizes and lengths by the contractor and the tube manufacturer prior to fabrication, lateral logging and accounting for each active and inactive connection, stabilization of void areas in the brick sewer prior to lining, and the development and documentation of required pre-lining and post-lining work.

The circumferential joints that join sections of large-diameter welded steel pipe play a critical role in the long-term serviceability of tunnel linings and pipelines. The two types of field-welded circumferential joints typically used are butt joints and bell-and-spigot joints (more commonly called double or single lap-welded joints). Lap-welded joints are quicker, and therefore less costly, to install because fillet welds take less time than butt welds and the fit-up between pipe sections is easier. Single lap-welded joints are common in tunnels where double lap-welded joints cannot be used due to lack of access. They have been used successfully on many projects and tests have shown them to have good ultimate strength. However, lap-welded joints are geometrically eccentric, which introduces additional stresses within the joint. As a result of this eccentricity, several case studies have documented the poor performance of lap-welded joints in earthquakes, which raises concerns about their use in regions of high seismicity. This paper presents a methodology for evaluating the performance of single lap-welded joints in large-diameter steel pipes that experience seismic longitudinal (or axial) loading. A simple two-dimensional analytical methodology that ignores the effect of hoop stresses is proposed. The methodology is used to calculate stress states and determine joint capacity as expressed by joint efficiency. The calculated joint efficiency can then be used to evaluate the performance of various joints under operating stresses and determine whether yielding would occur under seismic loading. Allowable joint efficiencies and joint details as proposed by various codes can be un-conservative in certain circumstances, since the codes do not address the impact of seismic demands. The methodology is applied to an example to demonstrate its practical application.

This paper discusses the application of trenchless technology for replacement of a 1500 foot section of failing concrete gravity sewer, which serves as an outfall interceptor for Kern Sanitation Authority's Wastewater Treatment Plant. Video camera inspection indicated that it was not feasible to rehabilitate the existing gravity sewer which passes beneath a major railroad, highway, irrigation canal and 4 lane overpass structure. Therefore, alternative technology was incorporated using bored and jacked steel casings and PVC carrier pipe to replace the concrete pipe. The existing pipe was then abandoned and filled from the inside to avoid collapse. The project was designed and administered by Kern County Waste Management and was successfully completed for about $805,000 total construction cost, approximately $535 per linear feet of sewer pipe.

Predictability is the key to any planning effort. Municipalities are often persuaded to keep rates low, and their cash inflow cannot keep up with the rising costs. However, at a time when construction costs are rising much higher than the rate of inflation, such predictability is often illusive. Adding to the lack of certainty, urban infrastructure projects are constantly faced with unique project characteristics that make predictability in costs far from the norm. With such issues facing the engineering and construction industry, presented below is one critical analysis performed for estimating the cost of the construction of water mains and the fascinating findings.

This paper presents a case study of a route evaluation and selection process for a 78-inch diameter raw water pipeline near a major metropolitan area in central Texas. The approach used by the project team during preliminary design of the pipeline was developed to take feelings and interpretations out of the route selection process as much as possible. A decision analysis software program was used in evaluating four alternative pipeline routes, ranging in length from 28,000 feet to 42,000 feet. Portions of the alternative routes extended through environmentally-sensitive habitat, road right-of-way, state highway crossings, relatively narrow and congested construction corridors, a lake crossing, suburban neighborhoods and steep topography. These and other differences between the alternative routes made it necessary for the evaluation and selection process to be based on quantifiable criteria that could be readily defended instead of emotions and feelings of stakeholders, owners, and engineers involved. The methodology used in identifying applicable evaluation criteria, establishing a quantitative rating system, and developing an unbiased ranking of the importance of each criterion will be discussed in this paper. Tabular and graphical presentations of data and numeric ranking scores will be included as examples to show how facts and not feelings should be used to select the best route for linear pipeline projects.

Trenchless pipe installations generally require restrained pipe for municipal potable water and sanitary sewer pipelines in Canada due to the methods by which the pipes are installed. Restrained joint pipe systems may also be required for traditional open cut areas with large axial thrust concerns, inadequate or inferior burial conditions, or a seismically sensitive area such as portions of British Columbia. In these cases, the pipeline systems used with frequency in the trenchless industry, become attractive to the open cut market with their inherently restrained and robust joining methodology. A relative newcomer to these types of pipeline applications is fusible polyvinylchloride pipe (FPVCP). This technology, comprised of otherwise industry standard PVC pipe that can be thermally butt-fused together much like high density polyethylene pipe (HDPE), is an attractive offering for water and wastewater municipalities who are used to working with PVC, but require a pipe joining methodology that dovetails with trenchless installation techniques and delivers a completely restrained joint. PVC has gained popularity in Canada due to its material properties which provide a strong plastic that can hold pressure in water applications and also does not corrode or materially degrade over its long service life -even in the generally colder Canadian climate. FPVCP adoption in Canada is increasing due to the unique features of economy in both trenchless installations and open cut — as well as owner's familiarity of the plastic. This paper will provide an overview of FPVCP technology and present the design, selection, and installation information for two pipe projects in Canada that utilized this material — an open cut installation requiring a restrained system and the other a directional drill (trenchless) installation.

The Lake Arrowhead Pipeline is a 13.5 mile long, 54 in. diameter prestressed concrete cylinder pipeline (PCCP), embedded cylinder type without shorting straps, and is one of the primary sources of water for the citizens of the City of Wichita Falls. Since its installation in the late 1960's, the pipeline has experienced eight catastrophic failures. After each failure, the City had only 72 hours of water available before their reserves were exhausted. After a series of studies beginning in 1993, the City hired a consultant in 2007 to assess the condition of this pipeline in a 5.3 mile segment which included most of the failure sites, to determine whether the entire segment or only specific segments warranted replacement. To perform the analysis, the Consultant selected Remote Field Eddy Current/Transformer Coupling (RFTC) technology. The total cost of performing the inspection and risk analysis along with the installation of access manholes and other necessary repairs was significantly less than the projected cost of replacing the 5.3 miles of pipeline. The method proved to be a prudent investment of the City's limited resources.

Current standards of practice for the design of steel water pipelines do not adequately and consistently address the potential longitudinal stresses in a pipeline, especially for high pressure applications. For steel pipelines, the low-pressure applications are typically designed using AWWA design manual M11 and the high pressure pipelines are typically designed using ASCE manual of practice for steel penstocks. In handling the longitudinal stresses in the pipeline due to internal pressure, both documents consider the Poisson's effect, but do not consider the complete pressure-axial strain relation (often known as Bourdon effect). In contrast, most mechanical piping designers use this effect in calculating stresses using piping analysis software, particularly for high pressure applications. Despite this shortcoming, current design practice for water pipelines has resulted in numerous successful projects. However, there have also been several failures due to excessive longitudinal stresses and poor or inadequate design of welded joints and thrust supports. This paper presents a comparison of current design standards by AWWA, ASCE and ASME and a proposed approach for estimating the longitudinal stresses for the design of buried pressure pipelines. Also, the paper presents a verification of this approach using a published case history of a pipeline failure.

The City of Stockton Municipal Utilities Department is moving forward with the Delta Water Supply Project (DWSP) at an estimated cost over $200 million. The project includes more than 13 miles of a 54-inch diameter raw water pipeline that will transport surface water from the San Joaquin River to the new 30-million-gallon-per-day (mgd) treatment plant. More than 7 miles of 36- and 54-inch-diameter treated water pipelines will connect the new water treatment plant to the city's existing distribution system. The pipeline design will resolve several challenges including difficult soil conditions, groundwater dewatering and tunnel crossings of major canals, interstate highway, railroad and major roadways.

Evaluation of longitudinal forces in welded portions of buried steel pipelines and the design to resist those forces has posed a dilemma for many designers. How should the various forces, such as thrust from pressure, temperature change, Poisson's ratio of the hoop stress, and possible sliding forces (soil drag) of pipe on a slope be determined and evaluated? Which forces are additive? What design stress levels should be allowed for each loading condition? This paper is intended to offer answers to these questions and to address conditions that can and have contributed to past failures. While there have been relatively few failures of such pipelines, they have been highly publicized due to the magnitude of the projects. It is important for the project owner to have confidence in the sustainability of any pipeline and to understand any contributing factors when managing existing pipeline assets. It is also important for the designer to understand the economics involved in their design decisions.

The Metropolitan Water District of Southern California (MWD) is retrofitting the Robert A. Skinner Water Treatment Plant (WTP) with new pretreatment consisting of raw water ozonation and expansion of their existing washwater reclamation system. This is a very large, fast track project that must meet a prescribed implementation schedule to maintain water production from this important 630 mgd treatment facility serving Southern California. The project includes furnishing and installation of piping up to 144-inch diameter. In order to meet critical milestones, MWD separated most of the large diameter piping (over 36-inch diameter) into a separate pre-purchase package. This required careful consideration and delineation of limits of responsibility to accommodate the expedited schedule and to result in a complete and functional installation. There were also several tie-ins to existing large diameter pipe that required careful coordination, including protecting the material integrity of the existing piping and limiting the period of time the plant would be removed from service. The routing of 5,600 feet of large diameter steel pipe, including 3,150 feet of 144-inch pipe, through both new and existing portions of the 630 mgd water treatment plant posed challenges to the design and construction of this major upgrade to this important facility. Special issues for the pipelines on this project included: making connections to existing pre-stressed concrete cylinder pipelines without causing immediate or long-term damage to the pre-stressed concrete cylinder pipe, consideration of the structural integrity of existing structures immediately adjacent to deep pipeline construction, maintaining pipeline grades that allow safe access for routine maintenance inspections during the pipeline's service, complexities associated with the fabrication and delivery of 12-foot diameter pipe and fittings. This paper will review the purpose of the project, and discuss the phased construction and other special issues confronted during design and construction of the project's large diameter pipelines. Design and construction solutions developed to deal with these issues will also be discussed.

Collapsible soils undergo considerable reduction of shear strength and deformation modulus due to water wetting. This paper investigates the effects of leak induced sub base soil settlement on deformation and stability of buried flexible pipes. Nonlinear finite element program (Z-Soil 2007) is used to model progressively increased wetting zone around buried HDPE pipes. Wet to dry ratios of deformation modulus, shear strength friction angle, and cohesion of collapsible soil were evaluated using oedometer, direct shear and plate load tests. HDPE pipes of 200 mm diameter and 25 mm thickness with sand bed and cover in the pipe zone and soil backfill up to ground surface were considered. Effects of progressively increasing wetting zone of 0.0 to 70.0 cm depth under the pipe sand bed were investigated. Staged backfill and surface pressure were considered. Results show increasing pipe invert vertical displacement and pipe deformation amplification with increased wetting zone in collapsible soil due to pipe water leak.

In the United States, the American Water Works Association Standard AWWA C900, Polyvinyl Chloride (PVC) Pressure Pipe and Fabricated Fittings, 4 In. Through 12 In. (100 mm Through 300 mm), for Water Transmission and Distribution, is arguably the most widely used of all pipe material standards for water distribution and transmission, as well as for sewer force main applications. Approved by the AWWA Board of Directors in June 2007, the latest version of the standard, AWWA C900-07, became effective on September 1, 2007. The new edition is significantly different from all previous updates in that it departs from status quo with regard to factors of safety, built-in surge allowance, treatment of occasional surges, and the treatment of recurring (cyclic) surges. The goal of the AWWA PVC subcommittee was to harmonize the new revision with other thermoplastic pressure pipe standards from AWWA and ASTM International. Other goals were to improve the design approach in order to more accurately reflect the material's capabilities and to allow greater precision when comparing AWWA C900 to other thermoplastic pressure pipe standards. The primary effect of these changes will be felt by the design engineering community in North America. This paper discusses thermoplastic pressure pipe design, and provides specific examples that compare C900-07 to the previous edition.

Flowable fill was used as the embedment material for an 84-inch diameter corrugated metal pipe (CMP) casing subsequently backfilled with 40-feet of cover. While the Bureau of Reclamation frequently uses flowable fill for pipe embedment, this particular installation was carefully monitored because of the unusually high depth of cover. The space between the casing and the 72-inch carrier pipe meant only minimal pipe deflection could be tolerated. Backfilling over the pipe started one week after the flowable fill was placed. Pipe diameter measurements were made after placement of the flowable fill and before backfilling, and then again 4.5 years later. The pipe deflection was insignificant.

There are several types of process flow and pressure needs for pipes that are included within water and wastewater treatment facilities. Some are low pressure applications and only require gravity flow, whereas, others piping systems require substantial thrust restraint. Typically, treatment plants are fairly compact with regard to location of buried structures and pipes and are generally designed with room for future expansion. This may require exposing buried piping systems and may impact thrust capability of pipe systems if they are not designed to accommodate operation during construction. This paper discusses the need for and selection of thrust restraint methods in treatment plant buried and above ground piping systems to accommodate pressure requirements and operation during expansion projects. Examples where this is important include surface water treatment plants and wastewater treatment plants. Particularly where there are significant area restrictions for the treatment plant site. Antelope Valley, East Kern Water Agency's (AVEK) Acton Water treatment plant Near Palmdale California will be reviewed as an example. This facility is located on a very small with a ruggedly terrained site, with only about 5 acres, with a fall of about 60 to 70 feet across the site. Pipes were designed and installed at this facility to accommodate the pipe pressures, tight spaces between hydraulic structures and anticipated expansion from 4 million gallons per day (MGD) initial capacity to 12 MGD. There was not adequate space for use of thrust blocks on the pipes requiring thrust restraint. Therefore, restrained mechanical joints were incorporated into the design. This allows the pipes to be installed in close quarters and does not compromise integrity for future expansion and connections, should digging near the pipe be required.

The use of horizontal directional drilling (HDD) has become widespread for the installation of many types of utility services including electric lines, water lines, gas lines, and fiber optic. The minimal amount of surface disruption incurred and reduced restoration required when utilizing HDD makes it a desirable solution for many installations. One type of service where HDD has been less commonly used is for the installation of gravity flow sewers, particularly those whose grade is less than 1%. This is largely due to the difficulty in maintaining accurate line and grade throughout the pilot bore and pullback portions of the installation. Nevertheless, HDD is a viable alternative for many gravity sewer installations. This paper discusses the various techniques used for gravity sewer installation with HDD and discusses the advantages and practical limitations of each method. Included in the paper is a discussion of a novel system developed by the Charles Machine Works, Inc. (CMW®) to verify that proper grade is maintained during the pilot bore portion of the installation.

The rehabilitation and replacement of sewer service laterals has traditionally been a difficult, expensive and time-consuming job. They are usually located directly beneath someone's yard, a business entryway or a sidewalk; all of which make open cutting the least attractive lateral rehab option from the resident's point of view. An explosion in lateral pipe bursting has come about recently for several key reasons. Inherently the method is well suited for lateral replacement. It provides a trenchless option for lateral replacement that utilizes the existing line and allows for increase or upsize of the original host pipe diameter.

Accurate pipeline condition assessment is vital to developing a cost effective and sustainable buried asset management system. Maintenance and rehabilitation of pipeline systems pose a major challenge for most municipalities in North America given their budgetary constraints, demand on providing quality service, and the need for preserving their pipeline infrastructure. This paper presents the proof-of-concept for an automated buried pipeline condition assessment system that can provide additional depth perception of defects in addition to surface assessments provided by current technologies. An ultrasound acoustics-based methodology is proposed to acquire depth perception and complement 2-D crack features available from the SSET camera. Experimental results show that the ultrasound immersion methodology provides rich data for building a reliable defect detection and condition assessment system. The proposed automated inspection system can lead to overcoming many limitations of the current manual inspection practice and can provide a more accurate assessment of buried pipe conditions.

The Reclamation table of presumptive E' (Modulus of Soil Reaction) values appears in many standards, guides, and manuals. The E' value represents the stiffness of the soil placed on the sides of the pipe and is used for estimating the deflection of buried flexible pipe. In the Reclamation table, E' varies with the type of embedment soil and the degree of compaction, but not with the depth of cover over the pipe. However, soil moduli generally change with confining pressure. Accordingly, some standards and guides have recently expanded design tables showing E' varying with depth. This study is a new analysis of forty-five field tests where deflection was measured as the depth of cover over the pipe increased. The data show a strong linear relationship between the vertical deflection and the depth of cover, indicating that E' does not vary with depth. Consequently, tables including E' variation with depth may not be warranted for design use for pipe with cover of 25 feet or less, and in many cases, 50 feet.

Because of the use of trenchless technology in the construction of the underground pipeline, it creates problems to detect and accurately locate buried utility. For this purpose, this paper study on detecting long distance & super deep pipeline installed by horizontal directional drilling (HDD). It covers both the fundamentals of the electromagnetic technology and practical applications. The paper begins with the cylindrical magnetic field used for locating wires, pipes, and analyze the H_x, |H_z|, ΔH_x curves and their own normalized profile curves with different depth from 1 to 21 meters separately, also analyze their curves with 3 times electric currents with different depth from 3 to 21 meters separately, and study the applicable condition on using ΔH_x 70% for the determination of the depth of the underground pipeline is analyzed. The paper then proposes some inspection technologic measures to confirm its location and depth, a description is given to raise signal-to-noise ratio, including direct connection, frequency, and electric current and far grounding and so on. The interferential factor on super deep pipeline acquisition is studied. Finally, for showing the validity of this method, the paper describes two examples of probing long distance and particular deep pipelines whose depth is deeper than 5 meters in Guangzhou, PRC.

A lack of reliable information on the location of underground utilities can result in costly conflicts, damages, delays, utility service disruptions, redesigns, claims and even injuries and lost lives during construction activities. While the location of subsurface utilities might be found on plans and records, experience has often shown that the utility locations are not exactly as recorded or the records do not fully account for the buried utility systems. An engineering practice known as Subsurface Utility Engineering (SUE) has proven to be a welcome solution to providing this much-needed underground utility information. Combining geophysics, surveying, civil engineering, and nondestructive excavation technologies, Subsurface Utility Engineering can provide accurate mapping of existing underground utilities in three dimensions during the preconstruction phase to avoid unnecessary relocations, eliminate unexpected conflicts with utilities, and enhance safety during construction. The use of Subsurface Utility Engineering has become a routine requirement on highway and bridge design projects, and is strongly advocated by the Federal Highway Administration (FHWA) and state departments of transportation. A savings of $4.62 for every dollar spent on Subsurface Utility Engineering was quantified by the FHWA from a total of 71 projects. These projects had a combined construction value in excess of $1 billion. Qualitative savings were non-measurable, but it is clear that those savings are also significant and may be many times more valuable than the quantifiable savings. In addition to highway designs, Subsurface Utility Engineering is gaining strong endorsement by other industries and market sectors, involved with design of construction projects involving congested underground utilities. As China's economy grows at a rate leading many other countries, there are more and more utility conflicts occurring daily all over China. Current China best practices provide approximate utility location markings just before construction or the development of city-wide GIS databases. Both are intended to provide approximate location information and lack the precise and accurate depiction of underground location and characteristics needed for engineering and design of projects. There is no clear evidence that a defined process such as Subsurface Utility Engineering exists in China for the engineers, designers, contractors, project owners and utility owners. Such situations existed in North America prior to 1987 before Subsurface Utility Engineering was introduced. Since then Subsurface Utility Engineering has successfully decreased utility conflicts, saved project costs and improved safety by providing accurate utility information for engineering and design. Now, locating and Subsurface Utility Engineering both exist in North America. Locating provides a low quality level of service for construction needs, whereas Subsurface Utility Engineering provides a full range of high quality level engineering services for engineering needs. As we can see, Subsurface Utility Engineering can benefit the development of China's economy.

A Buried Duct/Pipeline Network (BDN) is presently under development representing a joint-use integrated system to facilitate future upgrades of buried communications (telephone, CATV) and power lines. The new type network, being developed through a contract with the U.S. Department of Transportation, provides improved, cost-effective hardware and practices relative to present direct-buried construction procedures, which do not otherwise allow for future upgrades or replacement of initially installed utility cables. The BDN supports and encourages present trends for placing utilities belowground, minimizing future problems with such installations. The shortcomings of conventional direct-buried construction methods can lead to road damage or safety hazards, including risk of gas or power line strikes during reconstruction activities, thereby jeopardizing continuation of the desired trends toward universal belowground facilities. The BDN may be deployed in a variety of applications, ranging from residential communities to thoroughfares and highways. Common applications include road-widening projects, or any other situation in which open-trenching construction is employed. The feasibility of the proposed network was successfully demonstrated during the Phase I effort, which included the participation of three major utilities. This paper provides details of the subsequent 24-month, Phase II study, which was initiated in 2007, and comprises the primary research and development effort.

The design of the shell and reinforcing members of a 120 in. x 120 in. bifurcation (wye branch) for the Olivenhain-Lake Hodges Pumped Storage Project in San Diego County, CA, was a major challenge because of the small acute angle of 34.6° and the high design pressure of 472 psi. The project design criteria for the shell of the wye and reinforcing elements limit the general membrane stresses to the lesser of 2/3 of yield strength or 1/3 of tensile strength of the steel and the surface stresses at points of geometric discontinuities to 3 times the allowable membrane stress. Although AWWA Manual M11 design procedure does not include calculation of discontinuity stresses, preliminary design of the wye and reinforcing elements in conformance with AWWA procedures does not lead to designs that are feasible to fabricate and transport due to the required thickness and depth of the crotch plates. Finite element analyses (FEA) were performed to verify a modified-preliminary AWWA baseline crotch plate reinforcement design and to predict the membrane and discontinuity stresses. Since the project allowable stresses of the baseline design were exceeded, additional FEA analyses were conducted using different crotch plate thicknesses and depths, different shell thicknesses, and additional localized reinforcement schemes. Crotch plates with T cross-sections could not be used because of the small acute angle. The design assumptions and the FEA results are the focus of this paper. The advantages of the nonlinear analysis due to the high discontinuity stresses will be discussed and the supporting data presented. The use of a steel reinforcing pin at the intersection of the crotch plates to reduce the maximum discontinuity effects is also discussed.

Jacking forces are recognized to be an important parameter for the design and installation of pipes through pipe-jacking methods. Moreover, during pipe installation, significant stresses and deformation can develop within the pipes and pipe joints. Although pipe-jacking force has been researched in the recent past, procedures for simulating the pipe deformation and jacking force relationship have not been widely discussed in the literature. In this paper, the so called "t-z" model is utilized for the solution of soil-structure interaction problem at a given stage of the pipe-jacking operation. This soil-structure interaction model can be applied to determine the load-displacement behavior and internal stresses of the structural element when subjected to a jacking force. Here we have applied the method to simulate a series of cases for assessing the jacking force-displacement behavior and pipe stress by varying the soil-structure interaction parameters. In addition, the analysis method is combined with a probabilistic approach to assess the effect of spatial variability upon the jacking force and pipe stress.

At a bend in a pressure pipeline, thrust force is generated according to the bending angle and the internal pressure. Generally a concrete block is installed at the bend to resist thrust force. However, it was reported that the concrete block could be one of weak points during an earthquake due to the inertia force of the concrete block. Therefore, in our previous study, the lightweight thrust restraint using geogrids has been proposed. In this study, shaking table tests were conducted in order to verify the safety of the lightweight thrust restraint in liquefied ground. From the results, it is found that the lateral movement of the bend with the proposed method was smaller than that with the concrete block.

Founded in 1918, the Washington Suburban Sanitary Commission (WSSC) serves the water and wastewater needs of more than 1.5 million residents in the suburban Washington, D.C., counties of Prince George's and Montgomery, Maryland. The town of Washington Grove, located in Montgomery County, was once described by the town's mayor as "a town within a forest, an oasis of tranquility and a rustic jewel in the diadem of the great free state of Maryland." The officials of Washington Grove, in particular, the residents of 4^th Avenue, practice the same environmental principles today as their predecessors did in 1937 when the town was incorporated. This strong environmental sentiment, coupled with a limited right-of-way and aged old trees (one dating back 250 years) along the bore path, made open-cut construction to install new water mains an undesirable option to the town. Engineers at WSSC chose to use the challenges of Washington Grove as an opportunity to introduce horizontal directional drilling (HDD) to the Commission as a viable method for installing new water mains. Research provides clear evidence that flexible restrained joint ductile iron pipe can be installed by HDD using a site-staging technique that is less obstructive and more urban friendly. (Carpenter, et al 2003).

The LVVWD Asset Management group embarked on its initial condition assessment program for bar wrapped steel pipe. The program consists of field investigation of known problem pipes, and evaluation of pipeline critical use. This paper will discuss the first two pipeline field investigations and technologies being considered for future field assessments. The two pipe pipelines investigated are a 16-inch steel mortar lined, mortar coated pipe (MLCP) that was investigated after experiencing a leak failure (Las Vegas Boulevard and Sahara Avenue) (LVBSA), and a 36-inch steel cylinder concrete, pretensioned pipe (SCCP-PT) investigated after a routine hydrant tap attempt (Sandhill - Lamb Transmission Main Pipeline) (SLMTP). The SLMTP is a primary transmission main with a direct source of the reservoir at the LVVWD Campbell Pumping Station. Pervasive corrosion pitting on the steel cylinder and a failed cylinder reinforcing strip were discovered on the transmission main when the tap-in attempt was made in August of 2004, prompting an initial condition investigation at that location. That investigation raised a concern that there could have been a manufacturing problem in the pipe as the chloride content in the mortar lining was found to be relatively high. It was important to determine whether the system, or portions of the system were at sufficient failure risk. The data gathered from this analysis provided information needed to decide if the conditions uncovered during the initial analysis from the East Desert Inn Road near Aloha Street location were specific to that location. The additional investigations ability to alleviate concerns over the condition on the one (1) mile section as a whole resulted in only a small section of the pipeline being replaced. This resulted in a savings of approximately $2.5 million.

Pomerado Pipeline 4 rehabilitation was a fast track infrastructure project, which required the relining of approximately 26,000 linear feet of prestressed concrete cylinder pipe(PCCP) water main in a little over 238 calendar days. The rehabilitation consisted of relining the 69-inch and 84-inch inside diameter(ID) PCCP using a collapsed steel pipe, followed by welding, backfilling the annulus with grout, and cement mortar lining. Due to proximity to existing residential areas and other environmental restrictions along the pipeline alignment within the City of San Diego, the relining work was accomplished from 15 access portals, set 1,300 to 2,600 ft apart, requiring a specially built transporter for carrying the collapsed steel pipe inside the existing PCCP via the access portal. The specifications imposed stringent requirements on the material procurement, fabrication, installation, welding, and non-destructive testing of pipe. In addition, since a portion of the pipeline was located in close proximity to the residential area, the restrictions on the working hours for delivery, installation, and welding made the construction schedule even more challenging. This paper describes some of the lessons learned during the Pomerado pipeline rehabilitation, which can be successfully implemented for similar infrastructure projects.

In a highly developed corridor along Ponce de Leon Avenue in San Juan, Puerto Rico, the Puerto Rico Aqueduct and Sewer Authority (PRASA) have a combined storm water and sanitary sewer collection system that conveys flows into their Puerto Nuevo Wastewater Treatment Plant. To reduce flows and treatment costs, a plan was developed and implemented to separate the storm water and sanitary sewer flows that will minimize disruption to the businesses along the corridor. The existing combined flow channel is approximately 10,700 feet long, located in the center of Ponce de León Avenue, which runs through a mainly business and commercial area within a heavily congested arterial. There are three one-way traffic lanes and a dedicated one-way bus lane. Many of these banks, governmental and private office buildings, will experience disruption during construction activities, so the new sanitary sewer lines had to be carefully planned to minimize impacts to traffic and to the local businesses. To minimize disruption where possible, the design team elected to construct two sanitary sewer collector pipelines, one on each side of the road so that service laterals would not need to extend across multiple traffic lanes. The following steps were followed to complete the planning, design and construction phasing of the project: (1.) Topographic mapping and surveying. (2.) Subsurface Utility Engineering. (3.) CCTV of the existing combined system channel to locate the existing sewer and storm water laterals. (4.) Alignment study for the new collector sewers. (5.) Identification of sections of sections of the collector lines to be constructed by other than open cut methods. (6.) Preliminary Engineering Report summarizing project design, construction sequencing, schedules and cost estimates. (7.) Geotechnical Report (8.) Final design (9.) Bidding (10.) Construction The paper will discuss all aspects about the project and describe the challenges and insights gained.

There are numerous utility locating/potholing companies in the U.S. This is evident when you open any phone book or service directory. A customer can request potholing service on any given day and fully expect the pothole service provider to perform the job exactly as requested with no questions asked, supplying location, diameter, and depth of the utility the customer is looking for. At first glance one might consider this ideal, however from the contractor's perspective "performing the job exactly as requested" can often mean wasted time and expense. In two case studies, the value of subsurface utility engineering is demonstrated from design through job completion. The significance of potholing using a reputable, experienced subcontractor and the ability to transfer field data into CAD drawings and lad based maps is demonstrated.

There is a growing interest in the utilization of structural CIPP liner for the rehabilitation of deteriorated gray cast-iron water mains. However, little data is available on the long-term performance of such rehabilitation systems with respect to static and cyclic internal pressures. Specifically, the impact of the size and the shape of the holes in the host pipe are currently not considered by available design methods. An experimental study was undertaken to develop mathematical relationships between the size and geometry of the hole in the host pipe and the burst pressure of the liner, taking into account both the liner's long-term mechanical characteristic and the loading history (i.e., cyclic loading). Long-term experimental cyclic pressure tests were performed on fully deteriorated pipe specimens lined with a glass fiber reinforced CIPP liner. The tests aimed at measuring the accumulated plastic deformation of the liner under the action of combined fatigue and creep. The specimens were subjected to 350,000 load-unload cycles (60-130-60 psi), the equivalent of 100-year cyclic loading in a typical municipal water distribution system, to evaluate the impact of this loading mechanism on the long-term burst pressure of the lined pipe. The testing program included a host-pipe with gaps ranging between 2" and 4" in diameter. Strain and deflection measurements were taken for each gap in the lined host pipe prior to, during and after each load-unload cycle. In total, over 10 million data points were taken. The data was subjected to a rigorous statistical analysis. Conclusions are made reading the accuracy of creep models commonly used for predicting the mechanical behavior of thermosetting liners, the effect of fatigue and cyclic loads on the long-term performance of glass-fiber reinforce structural liners, and the relationship between the hole diameter, hole orientation, cumulative cyclic loads and the long-term burst pressure of the liner.

Quality Assurance and Quality Control (QA and QC) are normally the contractual responsibility of the Construction Contractor; however, prudent Owners should also provide some level of QA to "check the checkers" and provide an independent level of assurance that the work is proceeding in accordance with the contract documents. The increase in quality of the constructed project will more than offset the time and money spent by the Owner on QA activities. This paper describes the typical roles of Quality Assurance and Quality Control personnel on pipeline projects and the practical applications in the field. The paper also describes some of the best practices for Quality Control inspections, testing procedures, testing frequency, and impacts of poor quality. In particular, the paper focuses upon the following QC activities: 1) In-place density tests and inspection of bedding, embedment, and backfill, 2) Internal pipe deflection measurements and inspections, 3) Field welding tests and inspections, 4) Inspections of heat shrink sleeves using weld after backfill procedures, 5) Hydrostatic and leak testing, 6) Testing of corrosion monitoring and protection systems, 7) Factory tests of pipe.

An experimental reinforced concrete pipe (RCP) installation is designed by University of Nebraska - Lincoln researchers and installed at the landfill of Lincoln, NE. The pipe installation consists of eight pipe segments, 48 in. (1219.2 mm) in diameter, installed under fill heights ranging from 5 ft (152.4 cm) to 20ft (609.6 cm). Pipe was designed according to a proposed design methodology, where, mostly the direct design method is followed while the 0.01" (0.254 mm) crack control criteria is eliminated. Four of the eight segments were over designed and the other four were under designed in terms of the height of fill they carry. Pipe segments were instrumented by eighty vibrating wire strain gages, and sixteen earth pressure cells. Field readings were obtained and monitored. The study is currently undergoing and the paper presents up-to-date findings of the experimental observations as well as inferences made regarding the RCP design considerations. Projected conclusions are such that the current design methods and criteria used for designing RCP are overly conservative.

The Santa Margarita River Crossing is part of a design-build project to replace or update three sewage pump stations and replace their associated forcemains within the Santa Margarita River watershed of the Marine Corps Base at Camp Pendleton (MCBCP) in San Diego County, California. It was determined that the portion of the sewer force main which originally hung from the Stuart Mesa Road bridge across the Santa Margarita River was ideal as a trenchless crossing and could be bored utilizing horizontal directional drilling (HDD). The existing geology and available data were reviewed and an exploration and laboratory-testing program was developed for geotechnical design of the HDD alignment. Scour was critical for the 100-year flood event, dictating the sewer be installed about 50 feet below the streambed. The sewer force main consisted of an 18-inch diameter HDPE pipe installed within a 28-inch diameter HDPE casing in a 42-inch diameter borehole. The HDD design was performed to evaluate the stability and the potential of a collapse of the drilled hole during the HDD installation, as well as the effect of a "frac-out" during HDD installation. There were several environmental challenges associated with this project including: Army Corps permitting; U.S. Fish & Wildlife approvals; schedule restrictions including installation of the pipeline under the river during late fall, but before winter rains; construction and seasonal restrictions within occupied California gnatcatcher and Riparian habitats; Drilling Mud Controls and Frac-out Avoidance Procedures; use of measures to protect the tidewater goby and aquatic habitat at the Santa Margarita River; and minimization of disturbance to wetlands and other waters of the U.S. The horizontal directional drill was successfully completed in November 2006. This paper will discuss the environmental, geotechnical, stream-bed hydrologic and permitting challenges that led to the design and construction decisions for this important component of Camp Pendleton's wastewater infrastructure.

Welded steel wye branches are a key component of most water projects where flows must be divided. They are also a specialty item that requires many engineering considerations. The design of intersecting pipes has been studied by many agencies over the years and good design guidance can be obtained from several sources including the American Water Works Association (AWWA) Manual M11, Steel Water Pipe: A Guide for Design and Installation, where the focus is determination of proportions of steel reinforcement necessary to resist internal pressure. However, fabrication of wye branches is often left to the fabricator and little guidance is offered. There are many design related issues requiring a high degree of skill on the part of the fabricator to complete the design and to make it function reliably as a safe, integral part of a conveyance system, as intended by the designer. This paper will address several areas of wye branch fabrication that are not well covered by other sources including steel selection, geometry, welding, heat treatment, and non-destructive testing. Welding code provisions can be a valuable resource and their contribution to steel wye branch fabrication will be explored.

The Peace River/Manasota Regional Water Supply Authority (PR/MRWSA) is a regional governmental agency that is responsible for supplying potable water to its member governments consisting of Charlotte, DeSoto, Manatee and Sarasota counties, Florida. The Authority is also responsible for developing new sources of water supply for its members to serve the region. A Regional System Planning and Engineering Study has identified potential new water sources. These potential sources include groundwater, surface water, and salt water, and are located throughout the Peace River area. Development of these potential sources as regional supplies will require continued cooperation of the area's utility systems and the construction of an Integrated Loop Transmission System (Loop System) to move water from existing and new sources to the areas of demand. The Loop System project will create a regional potable water transmission system interconnecting water systems in the Authority's four—county service area. The benefits of a Loop System will allow the Region to optimize and most efficiently utilize the Region's Resources. Interconnecting supplies with major demand locations provides the greatest flexibility to the region by allowing multiple sources to supply multiple areas of high demand. Major benefits of the Integrated Loop System include: 1) Provides for rotational capacity and ability to rest sources, 2) Provides for reserve capacity for emergency transfers, 3) Improves reliability and redundancy, 4) Better matches supply and demand on a regional basis, 5) Optimizes the financial investment on a regional basis.

The City of Atlanta is in the process of completely overhauling the city's water and sewer infrastructure in a period of only 10 years. Clean Water Atlanta is a $3.9 billion collection of projects and one of the most ambitious and costly water and sewer improvement programs ever undertaken by a major city in the United States. With many segments of the program already complete, three major sewer separation projects are scheduled for completion this year. The three sewer separation projects are: 1. The Stockade Basin Sewer Separation Project which involves construction of 59,000 feet of new sewers, 360 new manholes and 400 stormwater inlets with traps. 2. The McDaniel Basin Sewer Separation Project which includes construction of 65,000 feet of new sanitary sewers, 400 new manholes, 700 new sewer connections and 360 stormwater inlets with traps. In addition, 55,000 feet of water lines are being replaced. 3. The Greensferry Sewer Separation Project involves construction of 56,700 feet of new sewers, 381 manholes, and more than 900 service connections and replacement of stormwater inlets with traps. The project also included 48,000 linear feet of water distribution lines and service connections. Most of the construction on the three sewer separation projects was done using conventional open cut construction necessitating numerous sidewalk and street closures. However, trenchless construction has played a role in each of the projects with key segments where excavation was difficult or impossible being completed by microtunneling. Huxted Tunneling, Palmetto, FL had the tunneling contract for the McDaniel Basin project. Huxted crews made 17 drives to install 200 linear feet of 20-inch pipe, 1,145 linear feet of 24-inch pipe, and 3,531 linear feet of 30-inch pipe—all Mission Clay No-Dig Pipe installed by Slurry Microtunneling (MT). Huxted had the contract for all microtunneling on the McDaniel Basin project, and subcontracted an additional 2,204 feet of pipe installation completed by Pilot Tube Microtunneling (PTMT) to Allied Contracting, Sylvania, GA, a specialist in microtunneling, pipe jacking, auger boring, and liner plate tunnels.

One of the effects of explosive growth in the Southwest is the rising demand for expedited construction of major infrastructure to serve fast growing areas. As development in Henderson, Nevada extended farther from the City's central Water Reclamation Facility, the existing sanitary sewers have become overburdened, and the need for satellite treatment plants and larger diameter sewer infrastructure has arisen. In the summer of 2004, a 5,000-acre master planned community's updated Sewer Master Plan indicated the need to immediately evaluate the capacity of an existing sewer line. The flow calculations indicated that a 42-inch and 48-inch diameter sewer interceptor, which was thought to be a future pipeline, would be expedited through design and construction immediately by two major land developers and three engineering firms. Establishing the alignment of the pipeline presented many design and schedule constraints. Initially, the sewer would parallel an existing State of Nevada roadside ditch to the north and the existing overburdened sewer to the south. However, the pipeline would also need to connect flows from two existing sewers, be deep enough to allow for future upstream extensions under proposed Regional Flood Control facilities, and cross under newly constructed highway box culverts. The large diameter gravity sewer line needed to cross a newly paved 300 foot State Highway directly (St. Rose Parkway), extend into the embankment of a major unlined channel, and connect to a predetermined pipe invert at the termination of the project. Coordination with three government agencies further complicated the design of the sewer. The Nevada Department of Transportation (NDOT) would not allow the closing of any street crossings, and St. Rose Parkway (State Highway) was considered a `no cut' street. The City of Henderson would require full protection of the existing sewer during excavation of the 20-foot deep trench for the new pipeline and full protection of the pipeline located in the embankment of the unlined channel. In addition to the intricacy of agency coordination, the jurisdictional line between the City of Henderson and the County of Clark jogged across the proposed pipeline alignment at multiple locations. The design of the proposed sewer line appeared to be a standard pipeline project. However, back-to-back physical constraints coupled with a tight schedule were what made this project worthy of documentation.

The purpose of the National Clay Pipe Institute (NCPI) / New York City (NYC) Research Project was to evaluate alternate clay pipe installation systems to address the structural problems associated with construction practices in the City of New York. The standard installation method uses Vitrified Clay Pipe with high strength concrete cradles in an effort to provide a robust system and insure dependability and longevity. The type and location of the beam fractures indicated that the incorporation of a measure of longitudinal flexibility would result in the reduction and possible elimination of the structural concerns. A Research Protocol was developed and agreed upon by NCPI and the City of New York.

Since Prestressed Concrete Cylinder Pipes (PCCP) were first introduced more than thirty years ago the demand for the repair of PCCP has been growing in numbers and diversity in recent times. The current repair methods available (additional post tensioning, steel lining, cured in place pipes, etc.) do not tackle effectively the case of external repair for large diameter pipes inaccessible from the outside. Relining by Carbon Fiber Reinforced Polymer (CFRP) is an appealing solution to this issue, not only because it is an internal repair method, thus not requiring excavation, but also because it adapts to a large range of pipe diameters, and can be expedited with the assistance of automated equipment. The aim of this paper is to outline the considerations involved with both the external post tensioning repair method and the CFRP repair method. Comparative advantages and disadvantages will be discussed. Finally, an automated method for performing CFRP repair will be introduced that may expand the application of CFRP repairs beyond spot, localized repairs and provide additional qualitative improvements to the application process. Concluding paragraphs will explain that the rehabilitation and repair process is a combined effort between owner, designer, and contractor/installer.

As aging water infrastructure and increasing water supply demands become a fact of life across North America, attitudes towards leakage from water mains are changing. Water leaking from pipelines creates a slew of problems, such as cross-contamination, corrosion, and degradation of bedding soils, which can lead to pipeline failures. Water utilities and districts have gone through a learning curve of the key role leakage plays in pipeline failure mechanisms, and are becoming increasingly proactive. One target of the growing concern about leakage is the allowable leakage standard on new pipelines. A hydrostatic pressure test is essential to test structural and mechanical properties. While it was once the best tool available to test for leakage, allowing a certain amount of leakage was unavoidable; hydrostatic tests cannot detect the smallest leaks, and even if detected such leaks can be impossible to locate. Contractors facing a failed hydrostatic test spend enormous resources trying to find leaks, and suffer penalties for extending the length of the contract schedule. The Sahara® Leak Location System is a tethered inline sonic leak location (TISLL) technology that has the proven capability of pinpointing leaks of under 1G/hr, allowing for rapid repair of even such tiny leaks. Tarrant Regional Water District (TRWD) and Freese and Nichols Inc. (FNI) have chosen to take advantage of this proven technology on the Eagle Mountain Connection Pipeline, requiring that the pipeline be surveyed for leaks before the hydrostatic pressure test. This paper describes this project, including the approach and advances used to allow for full testing of the pipeline under hydrostatic pressures, and results to date.

Infrastructure projects designed to meet the growing demands of a water district do not need to be limited in size just because a small public agency manages the district. Case history of the Nacimiento Water Project proves this point. The Nacimiento Water Project (Project) consists of a sloping multi-port intake facility and pump station, two intermediate pump stations, three storage tanks, control center, and approximately 45 miles of transmission pipeline ranging in diameter from 36-inches to 12-inches, with the goal of delivering 15,750 acre-feet of raw water to communities spread across the county. The $176-million Project is owned, managed, and will be operated by the San Luis Obispo County Flood Control and Water Conservation District (District) located within the central coast of California, and is staffed full-time by only two county employees. Despite limited management resources, the District has produced a pipeline project that will successfully meet the growing water demands of San Luis Obispo County. This paper discusses the District's undertaking of the Project. Specifically addressed is how the District made this regional Project successful by overcoming existing political obstacles and mending community relationships, recognizing its limitations as a small agency, establishing strategies and setting goals, staffing the Project with an "army" of consultants, attending to the details of design through pipeline optimization and value engineering, and positioning the Project for successful bidding and bond financing.

Thrust force is generated at a pipeline bend due to internal water pressure. Commonly, the thrust force is resisted by the passive resistance acting on the pipe bend. In Japanese current design (M.A.F.F. 1998), the passive resistance acting on the pipe bend is determined based on Rankine's earth pressure theory. In this paper, new backfill methods using geogrid and gravel for buried bend were proposed. In the new methods, the geogrid and the gravel were installed in the passive area to improve the strength of the ground. In order to verify the effectiveness of the proposed methods, lateral loading experiments were carried out using a model pipe having a diameter of 114 mm. The passive resistance of the pipe increased in the case using the proposed methods. In addition, numerical analyses using the distinct element method (DEM) were performed to reveal the resistance mechanism of the proposed methods.

The concept of `criticality' plays a significant role in determining the management approach for water mains. Critical water mains are defined as those whose failure would have substantial economic, environmental or social impacts on the communities they serve. Whereas `run-to-failure' approaches are tolerated with non-critical water mains, critical water mains have almost no tolerance for failure. A sound management approach for critical water mains should be built on reliable condition state information and a proactive strategy for collection of this information. The variety of water main condition assessment techniques available to the asset manager coupled with their relatively high cost of deployment require a rational framework for technique selection. In addition, there is a need to rationalize and consolidate the condition rating information revealed by various techniques. This step is essential in order to standardize the decision-making processes (e.g. repair, conduct further tests immediately, schedule next inspection) across the system inventory. As such, the City of Hamilton is currently developing a standard management framework for its critical water main inventory. The framework is composed of two main components: 1) A condition assessment rationalization framework and 2) A condition rating consolidation framework. The assessment rationalization framework is composed of a set of matrices that help the asset manager identify the suitability of each technique (When and Where to use?), the needs associated with each technique (constraints, costs, and impacts) and the expected outcomes of each technique (data reliability). The matrices are especially useful due to the plethora of new assessment techniques being developed as they serve as a standard framework for technique classification and evaluation. The condition rating consolidation framework attempts to standardize the way the results of assessment techniques are interpreted and subsequently used to drive decisions. The framework is developed for Ductile Iron and Cast Iron water mains as they compose the majority of the City's critical inventory. The framework utilizes Fuzzy Logic and the Analytical Hierarchy Process to combine condition rating results into an overall rating for the condition state as well as the expected deterioration rate of the pipe.

During the last ten years, as innovation and performance have raised the bar for pipe joint design, and more computer-aided design resources are available, several design flaws and opportunities have become clear. While many pipe joint profiles appear to be written in stone, changes tend to occur "spontaneously" and often evolve without an integral consideration of seal design. Similarly, some new pipe technologies are evolving constantly and as a result, their joint designs must be updated frequently in response to structural profile optimization, manufacturing constraints and process improvements. In most cases, modifications are made hoping that the current seals will be able to accommodate to these changes. In general, joint design and seal design are taking place at separate stages, with limited opportunities for concurrent engineering. The fact is modern seal design concepts can be incorporated into an integral perspective of pipe joint design, aimed at taking better advantage of engineering and analysis resources to develop optimal sealing performance. Among these concepts are dimensioning based on geometric interference, seal stability during installation and assembly, avoiding assembly-locking tendencies, adequate seal reaction to pressure and allowable stress and strain. Other important considerations are manufacturing constraints, critical dimensional and operational scenarios and complementary functions, most importantly assembly restraints. This paper addresses some of these issues by presenting concepts on an accessible theoretical basis. They are illustrated with practical examples, resulting from the last 10 years of seal design practice for various piping industries.

There is no doubt that growth in human population and economic development strain the world's finite resources such as land, water, food, and energy. To maintain and improve quality of life, we need sustainable technologies and asset management strategies that meet human needs for limited natural resources. The lack of technical resources and limited experience in developing new and emerging underground technologies has created urgent needs for research, development and outreach throughout the world. An important element in addressing the underground infrastructure challenges is collaboration among international researchers, specifically from the major countries and world powers, where the problems and possible solutions may be addressed. The role of universities in bringing these stakeholders together is particularly important. Universities provide insights, conduct research, disseminate research findings, facilitate cooperation and development and provide educational opportunities for current and future professionals. Founded by National Science Foundation, The University of Texas at Arlington and the China University of Geosciences, this workshop brought together research expertise across various disciplines to utilize best resources relevant to solving underground infrastructure problems. The event provided an opportunity for researchers from both countries to target critical areas specific for each country, and capitalize on local recourses. The critical technologies identified by researchers focused on trenchless methods, utility locating, freight pipelines, and asset management. This workshop was an excellent opportunity to address asset management and sustainability of lifeline systems and develop collaboration strategies and joint research programs. The workshop and site visits were held in October 10–15, 2007, and included 14 U.S. professors, researchers, and representatives of Chinese universities, municipalities, government agencies and industries. This paper will present details of this workshop, results obtained, and directions for future efforts.

The installation of resin-impregnated felt tubes within cast iron water pipes can lead to wavy imperfections (wrinkles) if the external circumference of the liner exceeds the internal circumference of the cast iron pipe. A split-disk test apparatus has been developed and a series of laboratory experiments have been conducted to measure the strength of liners with wavy imperfections. The design of the test apparatus is described, and results are reported for liners installed within cast iron pipes of six inch nominal internal diameter. Results for three different kinds of imperfections are provided, where measurements of maximum hoop force are related to the imperfection size (wavelength and amplitude). Most tests resulted in failures at or in the vicinity of the wrinkles. As the wrinkle size increased, the ultimate strength of the liner and its strength at first cracking were reduced. However, the effect was more detrimental on the latter than the former.

The prediction of the remaining useful lifetime of existing pipelines is a critical aspect of any long term asset management program and the programming and prioritization of maintenance and repair activities. This is increasingly true for Prestressed Concrete Cylinder Pipelines as many installations have experienced catastrophic failures well short of their initial, predicted design life. This paper presents a methodology for lifetime prediction presently in use by the Great Man-Made River Authority in Libya and Tucson Water Department in the United States. The method utilizes several inputs for the purposes of predicting remaining lifetime including structural modeling and finite element analysis, operating environment and conditions, chemical analysis and corrosion algorithms. The model also utilizes visual inspection information, NDT verification from Electromagnetic Inspections and Structural Health Monitoring via an acoustic monitoring of PCCP for wire breaks to measure the accuracy and uncertainty of the empirical methods. The result is a comprehensive Pipeline Risk Management System (PRMS) that is utilized to quickly establish priorities and note locations where additional monitoring may be required to reduce the uncertainty of information provided by strictly empirical methods.

When a pipeline crosses an area with potential landslide, it could be subjected to combined loads. External load conditions can result in bending and subsequent rupture of the pipe. When compressive stresses cause buckling and rupture, the tensile stresses rarely cause failures. Reliable mitigation measures could be completed quickly at modest cost if pipe monitoring is performed with consideration of elastic-plastic deformations. This paper presents the response of thin-walled cylindrical pipe subjected to combined beam load factors and internal pressures, using a new engineering approach. The main focus in this paper is on experimental investigation of the pipe performance and validity of the supplementary numerical approach. This approach uses formulas for longitudinal force and bending moment as a function of deformational parameters. The relationship between material model parameters as input to the analysis and the elastic-plastic deformation beyond limit of elasticity is investigated by performing a series of experimental tests. The applicability of the proposed formulas for the local plastic deformation assessment is also discussed.

Patented trenchless sewer repair products were brought to the market in the 1970's by well financed companies. These companies had the financial power to hire competent engineering staff and conduct the needed Research and Development as well as ensure quality installations. They also had the benefit and tradition of professional engineering involvement in public projects. Continued solid financial resources were generated since all products were protected by patents. In the early 1990's several major products come onto the open market resulting in fierce competition. Many small businesses took the opportunity to compete, forcing down the prices. This trend introduced cheaper and lower quality products into the process and undermined the selection of high quality long lasting products. This situation was exacerbated by the lack of standards that would adequately address quality and durability. Asset management of.any rehabilitation project needs a standardized procedure to be reliable and verifiable. As will be shown below, Service Life is important when a variety of products are offered in the bidding process since different products usually have different Service Lives. This paper offers guide lines and a standard method of calculation to optimize asset management related to sewer repair.

In September of 2007, the San Diego County Water Authority (SDCWA) initiated a project to evaluate leak detection technologies applicable for large diameter water transmission mains. One of the selected technologies was an un-tethered, free-swimming acoustic leak detection device that could be released into the pipeline's flow. The purpose of the project was to evaluate the technology's ability to identify and locate potential leaks in a large diameter water transmission main over an extended distance. The free-swimming acoustic leak detection device demonstrated an ability to successfully identify and locate leaks in large diameter water transmission pipelines. The device was inserted into a fully operational pipeline and was released into the flow stream to monitor many miles of pipeline during a single deployment. A 4" diameter access was required for both insertion and retrieval of the device. Because the device traveled in the water column and passed directly adjacent to the leak, it clearly and distinctly identified the noise signature created by each leak. The position of the device was tracked and recorded by an acoustic receiver on the surface. This recorded data allowed for correlation of any identified leak with the position of the device in the pipeline. This paper will address the actual field performance of the free swimming acoustic leak detection device as utilized for the SDCWA project.

The need for rational maintenance decisions under uncertainty for municipal pipe infrastructure such as the water distribution system has been clear for some time. However, there have been substantial challenges associated with integrating optimization analysis tools to city inventories, and producing information of direct use to City Engineers. New features have therefore been programmed into a geographic information system (GIS), including the incorporation of an optimization routine, and aids to data processing. Considering the specific characteristics of the initial pipeline and soil geometries and materials, as well as established models for pipe material degradation with time, the new application minimizes total expected cost during service period or the expected cost per unit service period to evaluate optimal rehabilitation scheduling. The system is illustrated using the pipe system from industry partner, the City of Hamilton.

There have been several digital pipe scanning technologies for pipeline inspection and condition assessment. Digital pipe scanner means a method of inspecting pipes (usually sewer pipes) using digital optical sensor (digital camera) to scan the inner surface of the pipes. Digital scanning technology delivers not only high quality images, but also well-organized data to be imported into any database system with minimal data conversion and data loss. In the area of sewer infrastructure asset management, digital pipe scanning is one of the crucial technologies for easy inventory, accurate condition assessment and evaluation, and deterioration prediction modeling. An upgraded and new digital pipeline scanning technology is presented in this paper. The system adopted the image processing and software technologies in raw data acquisition, data calibration, image distortion adjustment, and generating reports, and exporting data to Computerized Maintenance and Management System (CMMS). The eventual objective of the research and development is to provide a complete solution for sewer infrastructure asset management that uses all the potential advantages of digital pipeline scanning technology. In this paper, digital image processing, condition assessment, and database management part of the solution is discussed, and future asset management development plan is described.

The scattergraph is a graphical tool that provides insight into sewer performance through a simple and intuitive display of flow monitor data. This tool can also be extended to evaluate the performance of pump stations, inverted siphons, and related structures under certain conditions. A flow monitor located upstream from a pump station, inverted siphon, or other structure can provide important information about their operating characteristics. This information is revealed any time a flow monitor operates within backwater conditions influenced by these structures. The addition of iso-Q lines to a scattergraph allows the actual performance of pump stations, inverted siphons, and other structures to be compared to anticipated performance. Practical examples from flow monitor locations throughout the United States are provided, demonstrating the scattergraph signatures of approach conditions to pump stations, inverted siphons, and other structures under various conditions.

A drainage system is an important part of highway and other transportation facilities. Poorly designed and constructed drainage systems can easily disrupt the function of highways resulting in economic losses. An outstanding drainage system can be compromised by effects of corrosion or erosion effects of culverts. The performance of highway culverts reflects the health of a transportation system. The aim of this study was to investigate the statewide trend of performance of highway culverts based on limited data of existing inspections in Ohio. Sixty culverts selected for inspections include, 25 concrete, 25 metal, and 10 plastic culverts. Though there were eighteen parameters of a culvert inspected, the overall evaluation and pH value were of interest in this study. The overall evaluation of culverts is based on a numerical rating system of 0–9 except age and pH, where 9 stands for the best performance of a culvert under consideration and 0 for the failure condition. The spatial analysis was applied to develop geographic distributions for the overall evaluation of culverts using grids of 1 x 1 km² to investigate the general trend for the culvert performance. Values of pH taken at culvert sites inspected were also treated as spatial variables for spatial analysis. Results show that the general trend of culvert performance was geographically close to that of pH values.

The Portland, Oregon, Water Bureau (Portland) has initiated a multi-faceted effort to better understand the condition of water system and to identify areas of high risk that were not being addressed. These undertakings have resulted in a more comprehensive view of the distribution system and spending priorities. Efforts to understand pipe condition and risk include: 1. Close interval potential surveys (CIPS) over steel pump mains with subsequent inspection where the survey indicated high corrosion potential. 2. Weibull failure analysis to predict useful life for cast iron (CI) pipe. 3. Service tap pipe coupon blasting and inspection for graphitization. 4. Identifying critical pipes with multiple breaks from leak records and GIS; 5. Assessing risk (likelihood of failure and consequences of failure) associated with vulnerable pipelines. Portland has prioritized pipe replacements using leak history for 20 years. However, only a few pipes besides small steel and galvanized mains have experienced more than 2 breaks in 30 years of recordkeeping, so we don't have many data points for assessing condition. Out of the over 91,000 GIS pipe segments that make up Portland's piping network, about 4,700 segments are on the high vulnerability list and are being rated for relative risk. Likelihood of failure is based on what we know about their physical condition and site conditions that could make failure more likely, while consequences are assigned using a matrix of potential consequences and their relative severity that was developed by a cross functional team. This paper will discuss some of Portland's recent condition assessment undertakings in greater detail, what we have learned, and how that knowledge is affecting the spending priorities within the Bureau.

The Walnut Lake No. 1 project located in Oakland County, Michigan consists of a deep pump station and force main and serves to virtually eliminate sanitary sewer overflows. A critical element identified during the preliminary design phase was the need to protect adjacent private groundwater wells from possible loss of service and reduction in water quality due to a lowering of the ground water table. Installation of the pump station required excavation to a depth of 50 feet. To quantify the potential impact, a model of predicted dewatering radius of influence was developed and the location of nearby wells identified. A $200,000 water supply and well repair allowance was included in the bidding documents. A formal plan of action was developed to guide the team in quickly and cost-effectively resolving homeowner complaints. A total of ten wells were impacted during construction for a cost within the original allowance amount. This proactive approach successfully eliminated legal action, severe customer complaints, and health and safety issues.

Stress corrosion cracking (SCC) is commonly observed in the form of a microcrack colony within a surface layer of degraded polymer exposed to mechanical stresses and a chemically aggressive environment. SCC results from strongly coupled mechano-chemical processes. We distinguish four stages of SCC: 1) localized material degradation leading to crack initiation, 2) individual stress corrosion (SC) crack propagation, 3) multiple crack interaction and crack clusters formation, and, 4) instability and dynamic growth of individual crack or a cluster of cracks leading to the ultimate failure. The duration of the last two stages of SCC is relatively short in comparison to the total time of SCC related failure process. Therefore, the duration of the first two stages of SCC serve as a conservative estimate of total time before failure. In this paper, we present a model with consistent results of the second stage of SCC. The proposed model improved the estimation of failure time. The scatter of crack initiation time presents the major part of uncertainty in failure time. Individual SC crack propagation is much more reproducible phenomenon than fracture initiation. Deterministic Crack Layer (CL) theory is employed to model the kinetics and duration of slow SC crack growth. SC crack growth is modeled by a system of nonlinear differential equations, which calls for a numerical solution. Comparison of cracks driven by SC and stress only is presented. Conventional plot of SC crack growth rate vs. the stress intensity factor is constructed and analyzed. In conclusion, an algorithm is discussed for a conservative estimate of the life of engineering thermoplastic submitted to a combine action of mechanical stresses and chemically aggressive environment.

Wastewater infrastructure, such as sewers, force mains, etc., maintained by various municipalities across the nation are at increased risk of failure due to (i) "out of sight out of mind syndrome"-they are buried underground and not easily accessible, (ii) are generally with little or no redundancy. Force mains are typically used to carry wastewater from a low point in the collection system and discharge it into an elevated portion of the gravity sewers or to the head works of the WPCP. They rarely undergo any inspection to identify critical defects before failure because of inaccessibility and continuous operation. The paper discusses three key aspects of the asset management system for the force mains of the New York City Department of Environmental Protection; development of asset inventory database, standards for inspection ratings and technologies for internal inspection. Feasibility of a selected technology using ultrasonic scanning has been demonstrated through pilot testing on a 100 ft pipe segment.

The City of Rochester, New York initiated a multi-phased water supply conduit modernization program for 28 miles of its Upland Supply system. The engineering planning for the project provided a comprehensive evaluation and a prioritized, fiscally sound, and multi-phased modernization plan. The project included comprehensive evaluation of leak records, leak record compilation and analysis, conduit evaluation, conduit rehabilitation and replacement alternatives; environmental, transportation, permitting and approval review, precise boundary, planimetric and topographic survey, mapping, corrosion evaluation, and hydraulic evaluation. The resulting conduit modernization plan is an economic and risk based program that includes an adaptive management strategy whereby conduit modernization priority can be updated based on recent break data.

The 2002 Cost of Corrosion Study, sponsored by the U.S. Federal Highway Administration (FHWA) and NACE International, found that the economic impact of corrosion to the U.S. was more than $276 billion annually. Within that number, $36 billion is the cost of corrosion for the water & wastewater industries, with about 20% of all water being lost from these systems each year. As this critical infrastructure continues to age and deteriorate, the need for more proactive corrosion control and prevention will increase. To address this key asset, NACE has recently approved the formation of the NACE International Water & Wastewater Advisory Council. The council will provide guidance and direction to the NACE Board of Directors on industry needs and how to best address the pervasive problem of corrosion. This paper will discuss the findings of the study and the development of this new council and its mission.

Over the past several years, ground penetrating radar (GPR) systems have been developed and improved upon to enable the accurate mapping of underground utilities and other structures. Many companies now consider the use of GPR a standard process in their Subsurface Utility Engineering (SUE) investigations. Systems have recently been introduced that deploy multiple GPR antennas on one platform to allow creation of 3D images of the subsurface for even more complete mapping. In addition, these 3D Radar systems have been augmented by multi-sensor electromagnetic induction (EMI) systems to help image metallic targets. These 3D Underground Imaging systems help engineers do a better job of mapping whatever is in the subsurface by producing high data density images of the target zone. Having such data available benefits stakeholders by aiding in project design and decreasing project delays due to unknown underground structures that may otherwise be discovered only during construction. This paper describes such a 3D Underground Imaging system and provides relevant case histories.

This paper summarizes two Prestressed Concrete Cylinder Pipe (PCCP) assessment projects, including the findings of the inspections and the decisions that WSSC was forced to make in light of the inspections results. The inspection revealed that there were isolated problematic locations on the mains that were classified to be in a moderate to high level of risk of failure. Given the condition of the pipelines, WSSC evaluated four options: continue pipeline operation without mitigating risk, capital project to eliminate risk, a periodic re-inspection to track their condition, or proactive asset management to manage risk. For several reasons described in the paper, WSSC opted to implement a proactive asset management system that relied on continuously monitoring the condition of the pipelines and detecting problems as they develop. Proactive repairs are then focused on individual pipe sections as needed. Several immediate repairs were performed on the mains and a monitoring system installed. WSSC is presently monitoring the condition of these pipelines and will implement structural strengthening/repair solutions to ensure their safety as needed.

Highway culverts and drainage structures have the peculiarity of being characterized as both buried pipes in small diameters with no access or worker entry and larger ones with the possibility of manual inspection and repair/renewal. As such, asset management procedures for culverts are a complex issue. Trenchless technologies are not disruptive to transportation systems and provide safer construction operations for both workers and the general public and are ideal solutions for culvert renewal projects. If they are used in the appropriate application, they provide extended design life to existing culverts and drainage structures that may double or triple the original design life of these assets. However, each trenchless method has its own capabilities and limitations, and should be selected based upon existing conditions in order to be effective. This paper summarizes a plan for conducting research on use of trenchless technologies for culvert asset management and renewal and describes the expected results. After completion, this research will provide a comprehensive study and decision making procedures for asset management using trenchless technologies to address the construction, renewal, renovation, and inspection of culverts.

Water hammer is known as a phenomenon that has adverse effects on pipelines. Closing rate of valves plays an important role in controlling this phenomenon. In the water hammer process, the water pressure rise and water discharge are inversely correlated. Therefore, a tradeoff curve (Pareto front) between water pressure rise and water discharge can be developed. Developing these Pareto front using traditional multiple-objective optimization models is always time consuming. Therefore, in recent years, several multiple-objective evolutionary optimization models have been proposed which can provide the Pareto-front with an acceptable computational time. In this paper, the Non-dominated Sorting Genetic Algorithms II (NSGA II) is used for developing the Pareto front. To predict the pressure rise and pipe discharge for a valve closing scenario, a simulation model is also developed using the Characteristic Method. The simulation model is then linked to the NSGA II optimization model. After developing the trade-off curve between the water pressure rise and the discharge, a valve operating rule is developed for each non-inferior point on the trade-off curve. The results show that the proposed methodology can be effectively used for reducing the adverse effects of the water hammer in pipelines.

The Ft. Polk Directorate of Public Works (DPW) has directed the Corps of Engineers, Ft. Worth District (COE) to analyze the existing water system infrastructure and determine its capacity to support existing and future use. In order to perform this analysis the Corps of Engineers created a hydraulic model of the Fort Polk water system. This paper describes the field work conducted to provide the data necessary to calibrate the hydraulic model.

Hydrofracture associated with HDD projects remains a serious concern for regulatory and permitting agencies, and the engineers, owners, and contractors that must obtain permits and regulatory approval for their projects. The cavity expansion model is the appropriate model for evaluating hydrofracture risks, specifically maximum allowable drilling fluid pressures, for the majority of HDD projects in soils. The tensile strength model, not covered in this paper, is more appropriate for HDD projects in rock, especially those with relatively shallow cover. Estimation of minimum required drilling fluid pressure to ensure cuttings are transported from the bore is also required. The solution for minimum required pressure derives from well-established fluid mechanics principles. This paper describes the cavity expansion model, presents step by step instructions for its application, and illustrates the process using example calculations from actual HDD case histories. This paper is intended to help engineers become comfortable with the approach, the results predicted, and their significance. Continued research is also encouraged to measure actual pressures on projects and compare against predicted minimum required and maximum allowable pressures. More accurate evaluation of hydrofracture risks, though, is only one step in reducing actual hydrofracture risks. Coupled with improved evaluation, improvements in practice regarding management of drilling fluid properties and drilling methods are needed. Contingency measures such as conductor casing, relief wells, and piezometers should also be considered for reducing risks on difficult, challenging bores.

El Paso Water Utilities, which serves one of the nation's fastest growing metropolitan areas, faced a daunting future in 1989, with dire predictions of water supply exhaustion, a growing water demand, and limited financial resources. The high population growth rate, arid climate, scarce water resources, aging water infrastructure, and growing economy combined to challenge the resourcefulness of the EPWU staff and policy makers. EPWU's asset management program includes the use of advanced condition assessment technologies and the installation of a state-of-the-art SCADA system to monitor and control water facilities. Like many pumped water systems, EPWU's is prone to transient pressures; and to detect the transient pressures, EPWU implemented the most intensive transient pressure monitoring program in the US, which at present consists of 19 continuously monitored stations. The details of this system, as well as the results and benefits are discussed.

Adoption of a suitable sewer pipeline condition classification protocol is recognized as an indispensable first step in world wide sewer rehabilitation industry. Various condition classification systems for sewers have been developed in this regard. These systems differ according to local requirements in which there is no integrated, unified sewer condition assessment protocol available. Therefore, in order to standardized sewer condition assessment procedures, there is an urgent need of developing such a system. This paper reviews the historical development of different sewer condition classification protocols. The protocols developed by the Water Research Centre (WRc), UK and by the Centre for Expertise and Research on Infrastructures in Urban Areas (CERIU), Canada, have been discussed in detail. In order to integrate both protocols, an unsupervised neural network model has been developed. The integrated protocols are verified by municipal practitioners and experts of the CERIU sub-committee for developing a unified sewer condition assessment system. The integrated models will assist municipal engineers in developing a unified sewer condition assessment system.

In this paper, a landslide prone area in Istanbul has been studied to show the seismic vulnerability of a proposed natural gas pipeline network. The area is located 9 km away to the north of the North Anatolian Fault Zone (NAFZ). NAFZ is seismically very active and a major earthquake is expected within the next 30 years. Due to the geotechnical characteristics of the formations and surface topography, landslides are another major problem in the area. In order to investigate the seismic vulnerability of a hypotetical natural gas pipeline system established in the region, parameters used were obtained from regional technical reports. The critical acceleration levels for the existing formations were taken from papers prepared for the region. The behavior of natural gas pipelines subject to permanent ground deformation and seismic wave propagation effects are examined and risks are highlighted.

To augment and develop renewable water supplies and promote collaboration with other water providers, the East Cherry Creek Valley Water & Sanitation District (District) constructed the multiple phase Northern Water Supply Project. This drinking water transmission system consists of a Reverse Osmosis (RO) membrane water treatment facility, 31 miles of 48-inch transmission pipeline, and three pumping stations. Delivery capacity will be 47-mgd on a peak day basis with up to 10 million gallons of storage, and more than 12,000 hp of pumping capacity. The primary transient control systems proposed for the Northern Water Supply System consist of integrated equipment operation at each of the pump stations. Each pump station is equipped with combination surge anticipator valves and pressure relief valves. These valves discharge to the suction piping of each pump station and, in turn, to the storage tanks. The tanks act to absorb transient waves and regulate peak pressures on the suction side of the stations, effectively isolating the systems from pressure and transients with an air break. In addition to the surge anticipators and tanks, stroking patterns for the ball pump control valves, anti-reverse ratcheting systems, and air vacuum valves play key roles in control transients. All elements of the transient control strategy play critical roles in protecting the entire facility from damaging surge conditions and require a comprehensive maintenance strategy to maintain proper operation and protection. After construction was complete, the design concepts were verified during system startup by simulating various modes of power interruption and monitoring the response of the pumps, valves, and equipment. Pressure tracing and water storage level changes were recorded for use in evaluating the effectiveness of the transient controls. Actual system response was superimposed on the simulated predictions. Comparisons indicated consistent but inexact system response and identified that the facilities could benefit from adjustment of the system controls. By taking a start to finish approach to a complicated system design, effective transient control was assured. The demonstrated benefit of system control adjustment based testing and verification of design was an essential step in completing a successful project with full protection of the District's significant capital facility investment.

Traditionally, transient pressures have been considered as a potentially destructive influence in systems, possibly leading to pipe or equipment failures and representing a threat to both water quality and smooth operation. More recently it has been realized that transient pressures also carry considerable information about system state and condition. This has lead to so-called inverse transient methods, where a transient signal is used to infer system characteristics and parameters. The current work goes further than even this, specifically by considering the possibility of permanent installations to monitor and assess the system's transient response. This paper describes a collaboration between the Regional Municipality of Peel, the University of Toronto, Earth Tech consultants, and the Pressure Pipe Inspection Company to bring this transient data into focus and to greatly magnify and explore its value. While the final verdict is not yet out, the overall performance of this monitoring system, initial indications are that fruitful and economic partnership between data, sensors and monitoring technologies is possible.

Control of hydraulic transients is of critical importance in the design of transmission pipelines. While horizontal alignment is a key element of conceptual design, there are issues related to vertical alignment which affect not only steady state hydraulics but also the transient characteristics of the pipeline. In the work summarized in this paper, the author developed horizontal and vertical alignments for a 48-inch raw water transmission line from a lake intake structure to a water treatment plant 27,000 linear feet distant. Steady state and transient hydraulic models were then developed from the preliminary alignments and the baseline condition was established. Full power pump trip transients were modeled and simple surge control options were evaluated to form the baseline. Modified vertical alignments were then developed to evaluate the transient characteristics of the pipeline with a tunneled section in place of a relatively high near-surface pipe segment. It was found that the tunnel option reduced the size of the hydro-pneumatic surge tank, but did not eliminate the need for it. While the control of hydraulic transients is not the only consideration in the determination of vertical alignment, it should be a major consideration and can be a source of value engineering.

In the 1990's, officials from Orangeburg County, South Carolina, approached Santee Cooper, the state-owned electric and water utility, with the prospect of creating a regional water system along the Interstate 95 corridor to encourage economic growth. Unfortunately, this section of interstate highway has even been reportedly identified as the lowest per capita income per mile of interstate. Santee Cooper was successful in developing and putting into operation a 30 MGD regional water system for wholesale customers northwest of Charleston, South Carolina. This proposal led to the planning and design of a new regional water system to serve six counties along the I-95 corridor. Hazen and Sawyer (H&S) of Charlotte, North Carolina (along with co-consultant Engineering Resources Corporation (ERC) of Orangeburg, South Carolina) was selected to assist the parties with the planning and design of this regional water system. Primary funding has been provided through federal government grants and allocations via the Water Resources Development Act (WRDA) and the House Appropriations bills. The project team was been expanded to include the Charleston District of the U.S. Army Corps of Engineers. The ultimate goal of this project is to provide a reliable and high quality drinking water supply to the residents and provide infrastructure to the region at an affordable price. The target wholesale price of water is less than $1.00 per thousand gallons. An additional benefit of this project is that many of the small towns will not bear the replacement burden of maintaining and upgrading their existing wells and treatment systems to meet the increasing drinking water standards. Hazen and Sawyer developed a preliminary engineering report for a water system consisting of 65 miles of water transmission mains initially ranging in size from 36-inches in diameter at the water plant to 12-inch diameter mains to ensure the pressures will fill each wholesale users' elevated storage tanks. The preliminary design process consisted of corridor studies for the lines, assessment of environmental and cultural resources impacts, and use of computer hydraulic modeling to plan the system. By tapping into one of the largest drainage basins in the eastern U.S., the project will maximize the sustainability of the water source. The original schedule for this project consisted of design, permitting and construction to be completed within 5 years. As the project progressed, the amount of funding available began to vary requiring the project to be divided into various transmission main reaches. Subsequent lack of federal funding due to Hurricane Katrina delayed the project for 1–1/2 years. As a supplement to the temporary setback in funding and schedule, Hazen and Sawyer developed a Management Plan to jumpstart the project, refocus the team, and set clear goals to move the project forward. Since that time, the project has restarted with construction of the water treatment plant and the first transmission main to be completed in 2008. While the original plan was expanded and adjusted, the Management Plan was invaluable in driving the project forward and helping all team members keep focus on the goal of providing water to an economically disadvantaged region.

Dalton Utilities constructed approximately 14 miles of water transmission main in 1962 and 1972 using 30" and 36" Prestressed Concrete Cylinder Pipe (PCCP). This pipeline runs from the water treatment plant through the center of their service area and also serves the Dalton carpet industry, the largest concentration of carpet manufacturers in the world, and thus is one of the most critical lines in the system. Dalton Utilities had experienced a failure on this line in 2005 and was very concerned about its condition. They had secured an estimate for replacing the line, and considered the operational impact of doing so. This option was not attractive. Dalton Utilities needed a complete investigation into the current condition of the line to determine what to do next. The Pressure Pipe Inspection Company was engaged in the summer of 2006 to plan a project that would identify distress in a 3.08 mile section of this pipeline. This paper will discuss the details and outcome of this project including the method used to precisely determine the existing condition of the PCCP water transmission main: Remote Field Transformer Couple (RFTC). Additionally it will cover the next steps taken by Dalton Utilities for rehabilitation and further inspections.

Water distribution system (WDS) design has been the subject of minimal improvements over the last decade, even tough the accessibility of computer modeling has increased. Water distribution pipes are designed to provide adequate pressure at distribution nodes and adequate velocity in pipes, usually with the use of a hydraulic solver coupled with the engineering expertise of the designer. Storage tank design is done by following some standard requirements considering minimal values provided by local guidelines. Storage tank allocation is generally done without taking into account the network capacity and robustness. As regards the position, tanks are generally located next to the distribution area with highest demand and considering other site-specific constraints. Optimal network configuration, in terms of hydraulic efficiency and water quality, is rarely considered. This results in long residence time generating the loss of disinfectant residual and favouring water quality degradation. Up to now, the optimization of the WDS design and operations have been mostly focused on sizing pipes and pumping schedules without taking into account storage tanks location, storage capacity and water quality. The purpose of this paper is to present a methodology to optimize water storage tank volume and location. This methodology will take into account hydraulic requirements as well as water quality requirements (minimize residence time in order to reduce disinfectant decay and disinfection by-product formation). The well-known "Anytown network" benchmark is used to test the new methodology.

On June 8, 2004, the 42-inch concrete pressure pipe, which supplies potable surface water to one of the City of Houston's (City) Water Pump Stations, failed flooding several residential properties. After failure of the pipeline, the City authorized Lockwood, Andrews, & Newnam, Inc. (LAN) to further investigate the cause of the failure, review operational procedures, and simulate in a computer model the conditions that led to the failure. The computer model indicated that a transient pressure surge had occurred, which caused the pipe to rupture and potentially damaged over 29,000-lf of pipe. The length of pipe thought to be damaged was later verified in the field. The model results were within 100-feet from where circumferential and longitudinal cracks were observed in the pipe. In a pro-active step, the City of Houston also called for LAN to assess the potential for damage to the refill lines of two other water pump stations with similar operational procedures, and recommend preventative measures against future water refill line failures. The results from the transient surge model indicated that a 36-inch refill line had potentially been subjected to surge pressures almost two times the pipe's rated pressure. However, when a section of the 36-inch refill line was removed and inspected as part of a current construction project, no visible crack pressures or damage was noted. However, it was later discovered that the 36-inch refill line, while also concrete pressure pipe, was bar-wrapped pipe versus the 42-inch that ruptured, which was concrete cylinder pipe. This paper will discuss how condition assessment of pipelines cannot be made solely by modeling, but requires looking at the "big picture" consisting of a combination of modeling, understanding of the system and construction of pipelines, field verification, and experienced engineering.

The City of Phoenix is currently in a multi-year program to investigate 150 miles of prestressed concrete cylinder pipelines (PCCP). The failure of a 60-inch pipeline focused the efforts of the investigation to a pipeline known as the "Superior" pipeline. The Superior pipeline is a 2.2-mile long, 29-year old pipeline that ruptured on October 3, 2006, resulting in extensive damage to the surrounding community. The pipeline was immediately shutdown and the failed section of pipeline was repaired. However, the condition of the remaining pipe and the potential for additional failures was a concern. To identify wire breaks, Pressure Pipe Inspection Company (PPIC) conducted Remote Field Transformer Coupling investigations. In addition, visual and sounding investigations were conducted by Openaka of Branchburg, New Jersey to identify internal defects. These investigations identified pipe segments that were in need of immediate repair prior to putting the pipeline back in service. This information provided baseline wire break information for the subsequent investigations. Prior to putting the pipeline back into service, 11,700 linear feet of fiber optic was installed by Pure Technologies allowing the City to acoustically monitor wire breaks in real time. This information was critical as the pipeline needed to be back in service to meet the high demand for water during the hot Phoenix summer. Real time wire break monitoring allowed the City and Brown and Caldwell to slowly resume the operation of the pipeline to prevent another failure. Monitoring of the pipeline was conducted from February 2007 through January 2008 and the pipeline was found to be extremely active with an initial average of three wire breaks occurring each day. This paper focuses on the investigations conducted and conclusive results relative to: 1) Benefits of multiple technologies for PCCP investigations, 2) Calibrated vs. non-calibrated curves for electromagnetic analysis, 3) Real time data collection through fiber optics to monitor pipeline conditions, 4) Verification of fiber optic results using electromagnetic analysis, 5) Pressure and surge monitoring.

In order to study the settlement properties of culvert section under high-filled embankment, the settlement of an culvert was monitored in-situ, and established FEM models, the agreement between the model results and the experiment data was excellent, moreover, settlement distribution of the culvert section were gained from the FEM analysis. The exponent curve fitting method is considered as the most effective one for culvert section settlement prediction. The FEM calculation results show that the settlement of culvert is greatly affected by the elastic modulus of the subsoil, when the elastic modulus of the subsoil decreased from 40 to 5MPa, the settlement of the culvert increased 4.39 times, and the elastic modulus of other material are insensitive to the settlement. The Poisson's ratios of the backfill and the subsoil have greater effect on the settlement too. The researches of culvert settlement property give technological references for design and construction.

In the late 1980s a well known shoe and apparel manufacturer launched arguably one of the most successful marketing campaigns ever by coining the phrase "Just Do It®." The phrase became so successful in fact it appeared to take on a life of its own. Consumers were left with a basic "can do" attitude and an undeniable desire to excel at their favorite sport. By simply using the product the consumer felt he or she could achieve his or her goals. Simplicity made the campaign successful. As simple as it sounds, the tagline can be applied to valve selection and maintenance. Every year, industry sales and marketing professionals have the opportunity to visit with clients from the consulting field, as well as municipal and private utility sectors. Discussions regarding valve applications for current and future pipeline needs, although unique in application and/or location, many times share the same core obstacles. These obstacles include an aging infrastructure, budgetary constraints, dynamic growth issues and maintenance. Although individually these elements are by no means simple, a dedication to a couple of basic issues can help achieve the goal of establishing what the United States Environmental Protection Agency (EPA) calls a sustainable infrastructure. These basic issues focus on the importance of valves during the design and maintenance of the pipeline infrastructure. This paper will address the importance of valve selection in the design process and the impact of a legitimate valve maintenance program for sustaining pipeline system assets. The significance of valve selection can be one of monumental importance. The amount of time invested in the valve selection process is sometimes relatively small compared to the time spent on other pipeline material selection. This can be due to the fact that initial valve costs are often proportionately smaller than the initial pipe material costs. This is especially true on longer pipelines. Similarly, valves can have less impact on layout and/or easement issues. The designer must take care not to let this lack of focus negatively impact pipeline design. Other factors such as convenience, or lack of time, sometimes result in valve specifications being published from a previous project without

The Champlain Water District (CWD) in South Burlington, Vermont serves a population of approximately 68,000 in 12 municipal water systems in eight communities in northwestern Vermont. The water system, which draws water from Lake Champlain, has an average daily flow of 10 million gallons per day (MGD). The CWD treatment facilities have completely redundant unit processes with the exception of an existing 28-inch spiral welded steel raw water intake pipeline and screened intake structure. The CWD determined that a redundant intake pipeline and intake structure was required to provide consistent, reliable water to its users. The District retained the services of Wright-Pierce (W-P) of Topsham, Maine, to design the new intake structure, intake pipeline, and connection to the existing raw water piping. W-P enlisted GeoDesign of Windsor, Vermont to perform geotechnical investigations of the lake bottom soils. The CWD's existing intake, located in Shelburne Bay on Lake Champlain, is approximately 2,600 feet from shore, in approximately 80-feet of water. The District performed extensive water quality monitoring and lake bottom bathymetry to determine the location in this area of the bay that had the most consistent superior water quality. It was determined that changing depth or location was deleterious to water quality. This led to a decision to locate the new intake pipeline roughly parallel to the existing pipeline, with the intake inlet at the same elevation as the existing intake. Based on their experience with the existing intake, the District provided W-P with several design criteria that they desired to be incorporated into the new intake: 1) New intake capacity of 25 MGD to meet future peak flows, 2) Intake screens to be located at same elevation as the existing intake screens, 3) Instrumentation and chemical feed conduits housed in a separate containment pipeline, 4) Intake materials selected to resist biofouling, in particular, zebra mussels 5) Hatch access required for diver entry at the intake structure.

The City of Houston maintains over 200 miles of large diameter water transmission lines which provide 350 MGD of surface water throughout the City. Over the last few years, The City of Houston has experienced failures of various large diameter water lines. The failures have ranged from leaks resulting from joint movement or corrosion, to catastrophic failures of Prestressed Concrete Cylinder Pipe (PCCP). The City is taking steps to manage their water infrastructure through a structured program of maintenance, inspections, rehabilitation and replacement. The Asset Management program begins by prioritizing the water infrastructure for evaluation under a Condition Assessment program. Existing lines are prioritized on the likelihood that they may have distress and the risk of property damage or water outages if a failure were to occur, based on criteria such as age, material of construction, past operation, maintenance history and redundancy, and organized into a GIS database. Each of these criteria is assigned a weighted value used to estimate the condition of the line. Physical inspections and testing of the lines can then be scheduled based on their theoretical condition. This type of planning helps the City to prepare for long-duration water shut downs for inspections, testing and maintenance to reduce the impact to customers. This paper describes the criteria used by the City of Houston to prioritize their Condition Assessment program and some of the issues and constraints faced to fully inspect existing pipe lines, and the process will be illustrated in a case study. The "South 60-inch Water Line" is a major transmission line carrying treated surface water from the East Water Purification plant in east Houston to Sims Bayou Pump Station in southwest Houston, and was ranked #1 on the priority list. Because this line was a critical feed to supply surface water to southwest Houston, nearly two years of planning and construction of new transmissions lines was needed prior to a long-term shut down. The case study will present the extensive coordination and modeling effort required to minimize impacts to the Texas Medical Center, the South's largest medical complex. At the center of the project is the need to perform a condition assessment of a 40 year old 60-inch diameter PCCP line. Impacts include the risks associated with the "what-if" scenario of an unexpected line failure, temporary water shut-downs and new construction needed to prepare for a long-term shut down for maintenance and inspection, and the condition assessment inspections themselves.

The Water Environment Federation's (WEF) Collection Systems Committee (CSC) has identified private lateral and inflow and infiltration (I/I) sources as difficult issues that many wastewater utilities may choose to address. Sharing information regarding various strategies for tackling some of these issues can be helpful to others facing the same issues. A CSC project team has collected information from public utility private property programs that address sewer lateral issues including rehabilitation/replacement, maintenance and I/I source control. Private property program elements such as funding, legislation and public education efforts have been documented and have been made available through the internet via a virtual library. The virtual library is housed at www.wef.org/PrivateProperty and is available for interested parties to access. This paper will present the private property virtual library (PPVL) collection built to date and provide an overview of the information gathered.

The introduction of restrained joint ductile iron is rapidly gaining acceptance as an alternative pipe material for municipal engineering applications using horizontal directional drilling (HDD). The boltless restrained connection offers flexibility, ease of assembly, and positive restraint against endwise axial separation due to pulling during trenchless installations. The main area of concern is the potential corrosive effects on the pipe from the bentonite-based drilling fluid used in the installation. This paper discusses the results of a field testing program to evaluate the performance of restrained joint ductile iron pipe installed by horizontal directional drilling. The research involved assessment of the installation durability and effectiveness of two combinations of externally applied, loose wrapped, polyethylene encasement to provide a protective barrier. The pipe was excavated immediately and at time intervals of four months, nine months, and thirty-four months post-installation to evaluate pipe material integrity over various time horizons. The study concluded that employing 0.02mm (8mil) linear low-density polyethylene encasement provided the best protection to the ductile iron pipe against corrosion from drilling fluid and soils with low resistivities.

The City of Phoenix is currently in a multi-year program to investigate 150 miles of prestressed concrete cylinder pipelines (PCCP). The failure of a 60-inch pipeline focused the efforts of the investigation to a pipeline know as the "Superior" pipeline. On October 3, 2006, an early morning failure of a large diameter pipeline occurred within an industrial area of the City of Phoenix. The pipeline failure was a result of corroded prestressing wires that weakened the strength of the pipeline to the point that failure was eminent. Rupture of the pipeline occurred at full operating pressure resulting on catastrophic failure, flooding and property damage. The City of Phoenix emergency response team removed the pipeline from service, assessed the damage, developed and executed a plan to repair the pipeline, and repaired the damage to the surrounding community. Although the damage was extensive, the emergency response team was able to repair the pipeline and restore the community in an expeditious time frame. This paper focuses on the efforts taken by the City of Phoenix during the failure and repair including: 1) Emergency response planning procedures, 2) Maintaining uninterrupted customer service, 3) Community relations and damage control, 4) Repair of failed and compromised pipelines, 5) Failure causes and forensic investigations. Through comprehensive emergency planning and immediate team response, the City of Phoenix successfully met the needs of an emergency situation to maintain the service and satisfaction of their customers.

As aging water infrastructure and increasing water supply pressures become a fact of life in North American cities, attitudes towards leakage from water mains are changing. Water audits are becoming part of the standard operation of water utilities, and the volumes of treated water escaping from pipelines are coming under increased scrutiny. Most urban utilities now have leak detection programs to reduce leakage from their small diameter distribution mains. Until recently, however, the large diameter transmission mains have been largely overlooked, due to a lack of concrete data on how much water loss originates in these pipelines, and a lack of effective technologies for locating all leaks on such lines. New technologies engineered specifically for leak detection in large diameter water mains have now emerged on the market, and empirical data is available on actual leakage rates from large diameter mains in urban environments. This paper combines results obtained in Dallas, Philadelphia, Allentown, Montreal, and Toronto, and presents a discussion of the number of leaks, their volume, and their distribution, as well as a comparison to the expected results. Cost / benefit analysis will be presented as well when possible.

Polyethylene encasement has been widely promoted as a corrosion control method for ductile iron pipe (DIP). However, much of the data regarding polyethylene encasement that have been provided in industry promotional efforts have been from random test pits and from carefully prepared test sites. Independent corrosion engineers have reported on actual field evaluations of in-service polyethylene encased DIP and independent research has been conducted to evaluate the effectiveness of polyethylene encasement. This paper discusses the results of the independent research and reveals the findings of independent evaluations in terms of the condition of operating polyethylene encased ductile iron mains.

CH2M HILL has been and is the Program Manager for several municipalities across the United States that have entered into Consent Decrees with the Environmental Protection Agency (EPA) to reduce sewer overflows and help improve area waterways. Major Consent Decree goals include reducing the amount of inflow/infiltration (I/I) that enters the collection system. CH2M HILL has developed the procedure for assessing sanitary sewer systems through Basin Characterization.

In May 2007, the City of Anaheim (City) updated their Combined Central Anaheim Area Master Plan of Sanitary Sewers (CCAAMPSS) originally completed in September 2006. This 2007 update (Addendum) evaluated alternative pipeline alignments for the proposed build-out condition and included new connections into the regional agency's (Orange County Sanitation District) trunk sewer. This resulted in a significant reduction in build-out flows in downstream sewer mains. In June 2007, the engineering design team (City and Psomas) proceeded with design of the Citywide Sanitary Sewer Improvement Program/Project (CSSIPP) Group 3 in the area downstream of the Addendum improvements. During the preliminary design phase all potential diversions and alternative alignments were explored with the intent to maximize the capacity of the existing system and reduce the needed improvements. Additional preliminary design services included supplementary hydraulic modeling to evaluate the reduced flow rates, verify the various flow diversion strategies, and pipeline alternative alignments. A primary strategy of this additional analysis was to optimize the use of available capacity in the City's existing Interstate-5 Freeway (I-5) 24-inch [61 centimeters (cm)] and 33-inch (84 cm) sewer crossings. With projected build-out flows, the existing 24-inch (61 cm) sewer crossing has a depth over diameter (d/D) ratio of 83%, which exceeds the City's maximum criteria of 75% (equating to a capacity deficiency of 0.93 cubic feet per second (cfs) [0.026 cubic meters per second (m³/s)]; while the larger, 33-inch (84 cm) crossing to the north has a d/D ratio of only 65%, providing over 2.3 cfs (0.065 m³/s) of available capacity. Based upon these results, model flows were diverted from the 24-inch (61 cm) crossing to the 33-inch (84 cm) crossing approximately one mile (1,600 meters) upstream. Selecting this location for the diversion proved to be significant, since it not only balanced the projected flows in the two freeway crossings closer to their design capacities, but also relieved the capacity constraints in other downstream pipelines. The modeling indicated the proposed flow diversions nearly eliminated all remaining local deficiencies noted in the Addendum. This extended evaluation of the City's 2007 Addendum to their 2006 CCAAMPSS at the project design level generated an innovative solution providing a significant cost savings to the City. This is afforded by the recommendation to constructing diversion structures rerouting flow to the existing 33-inch (84 cm) I-5 Freeway sewer crossing. The financial impact of this recommendation to the City should result in savings of approximately $6.9 million (August 2006 dollars) in construction and engineering costs, as well as avoiding impacts from major construction within these heavily traveled roadways. In summary, the analysis demonstrated a strong partnership between the City and Consulting Engineer resulted in an innovative and cost-effective sewer improvement program.

How can you plan your Capital Improvement Budget without knowing the deterioration rate of your infrastructure? Software tools can assist asset managers in performing condition assessment, determining the deterioration rate of their municipal infrastructure (sewer, water, storm and roads) and producing capital improvement plans based upon time, budget and level of service. This presentation describes the use of CASS CIP®, an innovative Capital Improvement Planning (CIP) solution, and illustrates project results throughout the country. A common result of Asset Management Programs is to prioritize CIP projects and determine funding strategies. Municipal Infrastructure Capital Improvement Planning is like using an Etch A Sketch®. The left knob controls time, and the right knob adjusts money. The resulting picture that appears on the screen is the level of service and sustainability of your critical assets. Like effective Capital Improvement Planning, manipulating both knobs at once (time and money) is a true test of coordination.

In cooling-water lines of nuclear, coal-fired, and gas-fired power plants, large-diameter pipelines are used to convey water between the cooling towers and condenser heat exchangers. Several failures of cooling-water pipes raised the awareness of the risk of pipe failure and high costs of repair and loss of revenue from power generation. Inspection and repair of the distressed pipe pieces needs to be performed during planned outages. A power plant outage typically lasts between one and four weeks and occurs at three-or-more-year intervals. Since failure may result between inspection and repair time if a high risk pipe is left without repair, a program needs to be developed to inspect, assess the risk of failure, and repair of distressed pipes at high risk of failure during the same outage. This paper presents the results of a 108 in. diameter pipeline inspection, failure risk analysis, and repair of pipes during a two-week outage at the Tri-State power plant in Craig, Colorado. The cooling-water lines were inspected using electromagnetic inspection and on-site risk assessment of pipes with broken wires. Internal inspection and repair prioritization was performed at the beginning of the outage. CFRP and post-tensioning pipe repairs were designed prior to the outage, and a contractor was on standby so that the pipe pieces with the highest risk of failure could be repaired during the same outage. Four pipes were repaired using either internal CFRP lining or external post-tensioning within the scheduled time frame.

The problems associated with inaccurate buried utility location are causing increased traffic congestion in cities worldwide, so are of concern to all stakeholders involved in utility service provision. Therefore, a small group of key UK stakeholder representatives have been attempting to raise awareness and, following significant industry lobbying and government acknowledgement of the research needs, academic funding was obtained through a novel UK system drawing together a highly multidisciplinary mix of participants. This identified a need for a multi-sensor location tool, improved mapping technologies, integration of existing and newly-derived data, and asset tagging, resulting in a research programme entitled Mapping the Underworld (MTU). This paper describes MTU and its belief that what is largely hidden as a result of its burial should not be forgotten when setting priorities for funding. It is also described as an important example of how a coherent research strategy can lead to an acceptable solution if it is not treated as a single, stand-alone project — as so many classically academic research projects are. It will conclude that an holistic approach is required to address the complex problem of utility location, which requires collaboration between disciplines, with other research projects and, most importantly, with the stakeholders intended to benefit from the research.

In order to optimize the expenditure of its sewer rehabilitation budget, Athens-Clarke County, GA has developed a comprehensive defect assessment program which identifies and characterizes problems and prioritizes rehabilitation. The County allocates $1 million per year for rehabilitation of pipes that are not candidates for near-term replacement. The sewer system serves 110,000 residents, and its problems are not unique. The system features 425 miles of pipelines with a median age of 40 to 50 years. Some downtown pipes are as old as 120 years. Older sewers are constructed of either clay or ductile iron bell and spigot with oakum gaskets and brick manholes. Tree root intrusion is common, as are significant infiltration and inflow. Many pipes were laid at minimum grade and are very sensitive to increased hydraulic roughness. The defect detection and assessment program utilizes multiple tools including video recordings from closed circuit television (CCTV) cameras, smoke testing, fixed electrode leak detection, longitudinal water chemistry profiles, and manhole visual assessments. Longitudinal water chemistry profiles evaluate changes in conductivity, temperature, biological oxygen demand, and total suspended solids between samples taken from successive manholes. Using smoke testing, manhole inspections, and CCTV, the County assessed 14,000 feet of 24-, 30-, and 36-inch sewer and 42 manholes. A defect prioritization schedule was developed, and the County used a contractor already under contract to conduct the remedial work required. The County's environmental sampling and right-of-way maintenance crews conduct day-to-day inspections and are highly knowledgeable about sewer conditions. This information is then juxtaposed with the County's Service Delivery Plan — a plan that assesses the existing system, projects flows for the next twenty years based on the current land use plan and then identifies the parts of the system that will be out of capacity and future pipelines needed to add service to previously unsewered portions of the County. This comprehensive system of defect assessment and characterization has been very successful in identifying the worst problems, ranking the others, and creating a database of pipeline conditions. To date, ACC has successfully used the cured-in-place pipe method to rehabilitate 6,800 feet of 36-inch interceptor and 8,500 feet of 12-inch sewer. Comprehensive defect assessment and prioritizations helps Athens-Clarke County maximize infiltration/inflow (I/I) reduction using appropriate technology for each defect; maximize the value of each rehabilitation dollar expended; and maximize the use of an existing Contractor to reduce overall project schedule and budget.

Polyethylene encasement has been the primary asset preservation method utilized for gray and ductile iron pipe since 1958. In the 50 years of use, over 300 million feet of iron pipe have been installed with polyethylene encasement, and over 300 miles of encased pipe installed with supplemental cathodic protection. This paper reviews the history, successes, problems, and limitations of this method of protection. Failure investigations of polyethylene encased pipe by the author over the past 35 years are discussed. Recommendations are given to ensure the design service life of encased ductile iron pipelines is achieved.

Safety on any construction project should always be the first concern. Many dangerous work environments are not given the respect they deserve, and without adopting recognized safety guidelines, many projects can be considered at risk. Experience has shown that many confined space entry programs and criteria differ between private, municipal and state sanctioned guidelines. As the need for the rehabilitation of large-diameter pipes continues to rise, education on the topic of safe work practices in confined spaces becomes a greater necessity for the municipal engineering community. This paper will focus on one of the most stringent safety guidelines in North America, as defined by the California Dept. of Industrial Relations, Division of Occupational Safety and Health (Cal/OSHA) — Title 8 regulations (T8 CCR, California Code of Regulations). While man-entry pipeline work may be defined in many states as only Confined Space Entry, some municipalities in the State of California, such as the Metropolitan Water District of Southern California (MWD), requires that Contractors engaging in this type of work conform to regulations of Title 8, Chapter 4, Division of Industrial Safety, Subchapter 20, Tunnel Safety Orders (Section Section 8400 – 8568). The management team of Fibrwrap Construction, Inc. (FCI), in an effort to provide the safest work environment for its man-entry Pipeline Rehabilitation Team, performs all projects in accordance with Cal/OSHA Mining and Tunneling Unit guidance. This paper will highlight all measures put into place by FCI to ensure the safe rehabilitation of Prestressed Concrete Cylinder Pipes (PCCP) using Carbon Fiber Reinforced Polymers (CFRPs). It is hoped that municipalities throughout North America that are in the process of renewal of their PCCP and other large diameter pipelines will adopt these safety guidelines or at least incorporate some of the important aspects of the guidelines into their safety standards.

The San José Sanitary Trunk Sewer is a key component of the wastewater conveyance system that serves the San Juan metropolitan area. This trunk line conveys over 25 mgd of wastewater from the eastern, southeastern, and western portions of the metropolitan San Juan service area to the Puerto Nuevo Regional Wastewater Treatment Plant (WWTP). The last principal segment of the San José trunk sewer system is a 90 - inch diameter reinforced concrete pipe which passes under the former San Juan Landfill. The 90-inch diameter trunk sewer segment was installed in the 1950s and is approximately 700 meters long. This segment of the trunk sewer consists of a reinforced concrete pipe installed over wooden pile supports spaced at approximately 8 feet. The original ground surface consisted of alluvial soils from the bank of the Puerto Nuevo River, soil with limited structural capacity. For the past 20 years, the Puerto Rico Aqueduct and Sewer Authority (PRASA) has become increasingly concerned with the physical condition and hydraulic carrying capacity of this trunk line. During the 1970's, a sanitary landfill was constructed over the San José Trunk. Over the years, San Juan Landfill operations encroached upon the trunk sewer and the line was covered with, in some cases, in excess of 40 feet of refuse. The additional loading from the landfill was not considered in the original design of the concrete pipe. In the 1980's, PRASA obtained a Court Order to restrain the San Juan Municipality from continuing to deposit solid waste over the trunk alignment. Since the line is constructed of concrete and has been in service for over 50 years, there is also a significant concern that the effects of corrosive sewer gases and leachate may have compromised the structural integrity of the pipeline. Prior evaluations of the trunk sewer have suggested that the structural integrity of the line may have been compromised by the load of refuse and overburden on the portion of the trunk line that runs through the landfill. There was concern that the trunk line may have settled in areas under the landfill, which could result in lost hydraulic carrying capacity. Additionally, manholes within the landfill have been covered over and appropriate inspection of the line could not be conducted to ascertain the condition of this important infrastructure element.

Structural condition of wastewater pipelines is often reported in terms of internal condition grades of 1 through 5, with 1 being the best and 5 the worst condition. The existing models and methodologies for structural deterioration of wastewater pipelines based on ordinary regression or ordinal probit regression violate the model assumptions, and lead to invalid results. Furthermore, the existing ordinal probit models for structural deterioration of Civil infrastructure are overly complex in terms of number of parameters to be estimated. This also makes the interpretation of these models fairly challenging. Another existing modeling technique based on binary logistic regression dichotomizes the data into pass/fail categories, and thus ignores the rank order information available in data. This paper demonstrates the shortcomings of existing methodologies, and presents an ordinal regression model based on cumulative logits with partial proportional odds for modeling the structural degradation behavior of wastewater pipelines. The proposed model is more parsimonious as compared to the existing ordinal probit models as less number of parameters needs to be estimated. The model is also more flexible as it does not assume an overly strict assumption of normally distributed error terms. The model also affords simple interpretation in terms of odds and predicted probabilities. Application, parameters estimation, verification of assumptions, graphical interpretation, and model validation has been demonstrated with real data from the City of Niagara Falls' wastewater collection system. The paper concludes with a discussion of the salient features of the proposed model, and its implications for wastewater systems' performance prediction research.

This paper presents the current Non-Destructive Evaluation (NDE) applications in pipeline inspection, making comparisons for different NDE methods. For the most commonly used NDE methods for pipeline inspection, such as ground penetrating radar (GPR), magnetic flux leakage, eddy current and infrared thermography, each of them has different capabilities of analyzing the pipeline defects with varying precision and has its own advantages and limitations. Finally, issues related to further research for pipeline inspection and maintenance is provided.

The increasing prevalence of reverse osmosis treatment water projects which produce aggressive water has led to a commensurate increase in the specification of stainless steel for process piping. Based upon material characteristics alone, stainless steel appears suitable for many of these environments, but neglecting how these piping components are fabricated and attached together can lead to otherwise unexpected corrosion problems. This discussion is intended for application to the austenitic stainless steels, (e.g., UNS S30400, etc.) or more commonly the "300 series." Austenitic stainless steels contain about 18 percent chromium and 8 percent nickel as their principal alloying elements. They are the most common types specified for waterworks because of their normally good resistance to atmospheric corrosion. Austenitic stainless steels resist corrosion because of the passive oxide layer that forms on the surface. They are readily welded, and the welds are generally tough and ductile, if properly made. However, the passive oxide layer is disturbed during the welding of joints. The welding procedure specification, which must be submitted for review by the engineer of record, will usually include the critical variables for ensuring that the properly made weld has adequate strength. What the welding procedure will not include are the techniques necessary to allow the weld and heat-affected zone of the base material to enjoy the same corrosion resistance of the base material. This paper addresses good specification and detailing practices intended to result in corrosion-free stainless steel pipe installations.

The Central Pipeline (CPL), installed in 1965, is a 66-in diameter, 12.6 mile pipeline owned and operated by the Santa Clara Valley Water District (SCVWD) in San Jose, California. Approximately half of the pipeline is constructed using prestressed concrete cylinder pipe (PCCP), embedded-cylinder type. Development in PCCP inspection technology has made it possible to detect distressed pipe with broken wires using nondestructive methods. Once distressed pipes are identified, a utility must determine whether pipe replacement, and/or pipe rehabilitation/repair, and/or continued monitoring/inspection is warranted. This paper is presented in two parts. The first part outlines the strategies used by the SCVWD to determine the appropriate course of action once distressed pipes were identified within the CPL. Spending more time up front to understand the magnitude of distress and failure risk of distressed pipe is recommended. This approach may seem costly and time consuming but it may pay off for the utility by savings on the cost of unnecessary repairs. In the second part of the paper, the results of failure risk analysis of distressed pipe in the CPL will be discussed. Failure risk analysis is based on the one hand on technology derived from finite-element analysis, hydrostatic pressure testing, and field observation of distressed pipe, and on the other hand on field inspection of properly selected sample of distressed pipe consistent with the desired reliability of the pipeline. In total, five pipe pieces were inspected using wire continuity test. All broken wires were found to have only isolated breaks related to the manufacturing process and unrelated to the corrosion of pipe or hydrogen embrittlement of wires. No repair or rehabilitation of the pipeline was necessary and there was no need for frequent inspections or monitoring.

Closed circuit television has become the de-facto standard for condition assessment of gravity sewers. These pipelines generally have access available through manholes that can be easily opened to the surface, and are not generally surcharged, making CCTV inspections with remote operated vehicles easy and effective. This technology is not often applied to pressurized water mains, for lack of an effective delivery mechanism that did not require significant service disruptions. This paper details the introduction of Sahara® Video, an adaptation of the Sahara Leak Location system which allows for CCTV inspections of in-service water mains. It describes how the patented mechanism used to pass a sensor through an in-service water main has been successfully used to introduce a CCTV camera into in-service water mains, and to survey long stretches of pipeline. Specifications for the system, as well as case studies describing projects to date, are presented.

Currently, municipalities are being tasked to develop improved systematic methodology for allotting their period budgets more appropriately so that their installed buried infrastructure is better utilized and sustained. While capital is typically spent on new infrastructure construction, the maintenance of the present infrastructure must not be neglected. When planning the allocation of investment funds, multiple objectives may exist which are dependent on the constraints, resources available for construction, and the interrelationships and dependencies among all of the alternatives. This makes the task of planning, prioritizing, and allocating funds a complex exercise. In 2000, the City of Edmonton, Alberta initiated a proactive approach to maintaining their wastewater assets by developing a financial outlay model called Proactive Rehabilitative Sewer Infrastructure Management (PRISM). PRISM uses linear programming to optimize allocation of funding for the local sewer network based on deterioration predictive modeling. A more robust version of PRISM was developed in 2002 and has been implemented into the City's asset planning strategy. This paper discusses the City of Edmonton's approach to asset management including assessment of the past five years and describes the framework of PRISM.

Gasketed joints are the most popular method for joining PVC pressure pipes for buried applications. While this method has proven to be very reliable over the years, it can be susceptible to installers "over-inserting" the spigot end of the pipe into the bells, which can introduce stresses into that area of the pipe. This is particularly common when mechanical means (such as backhoes) are used to assemble the pipe joints in the field. While the pipes are made with clear maximum insertion indications, installers often have trouble controlling the insertion depth, or are not properly trained to avoid over-insertion. These stresses, combined with excessive joint deflection (usually from installers trying to eliminate fittings), have been identified as a source of concern, therefore a research program, combining experimental testing and numerical simulations, was initiated to determine the magnitude and potential effect of these stresses on a typical PVC pipe installation. The FE results correlated with the experimental results showing that it is practically impossible to bring a PVC pipe to failure at the installation. Further, the results showed that only grossly inadequate installation procedures could have an effect on the long term integrity of the piping system. A design change to the bell end of the pipe was found very effective in reducing the risks of over-insertion and hence reducing further the risks of premature failure due to inappropriate installation methods.

The City of Regina, SK, Canada, has been developed on a post-glacial lake deposit, called Regina Clay. The deposit is highly plastic, unsaturated, expansive clay that exhibits large volume changes as the soil water content changes. The water distribution system of the City of Regina has about 530 km of asbestos cement (AC) water mains. The rate of water main breakage has increased recently in old areas. A study was conducted by the National Research Council Canada, Center for Sustainable Infrastructure Research in Regina to investigate the causes of failures of the water mains. Field instrumentation was successfully installed to monitor the performance of a replacement section of a 150 mm diameter AC water main in south Regina, where failures are frequent, to learn about soil behaviour and its interaction with this type of pipe. The instrumentation included sensors to measure pipe wall strains, in situ soil water content, soil movement, soil stress and temperature. Measurements were made in the pipe trench backfill and in the native soil around the backfill. This paper presents the first year monitoring data of the test section.

This paper discusses the requirements and techniques used to evaluate the condition of water and wastewater pipelines. Asset management practices have recently focused attention on the condition of existing pipelines. The assessment of these pipelines, including the logistical challenges involved in performing assessment, is becoming a critical issue for pipeline operators. External and internal evaluations are often required to provide an accurate assessment of pipeline condition, and to determine the remaining useful life. External evaluations may involve identifying locations of corrosive soils, known leaks, pipe settlement and recent construction in the area of the pipeline, among others. Excavation and in-situ testing of the pipeline allows direct measurement and documentation of the exterior condition. Reliable information on the condition of the pipeline interior often requires confined space entry into the pipe. The parameters that can be measured and their relative importance in evaluating the condition of the pipeline and establishing remaining useful life are discussed. Safety issues associated with confined space entry over 1,000 feet into a pipeline are also addressed. Today we are shifting from a mentality of building and operating assets to managing them. The goal of condition assessment, as a part of asset management, is to document existing facilities and address long term life cycle costs rather than the day-to-day issues related to meeting service level goals. Desktop studies are useful, particularly in Phase One of an effective condition assessment approach, but by themselves fall short of accomplishing the goals of effective asset management. Asset deterioration curves, for example, don't take into account manufacturing variability, site specific conditions, design parameters, methods of installation or operational conditions. These curves attempt to simplify what is a very complex operational system. The design for many of these systems is based on very specific design parameters, which may or may not actually be experienced during the actual operation of the systems. The condition assessment plan should consider as many of these variables as possible, and be performed on a case by case basis with some level of physical observation to determine actual operational conditions. Without the actual physical observations multimillion dollar decisions are being made on desk top estimates. Condition assessment of pipelines can be broken down into 3 phases. Phase 1 involves developing a work plan. Phase 2 is where the field work is completed and data is collected on the condition of the pipeline. Phase 3 develops repair and rehabilitation alternatives. This paper addresses Phases 1 and 2.

In 2003, the Clark County Water Reclamation District (District) assessed their practices, procedures, equipment and systems utilized at that time to manage the District's wastewater collection system. The goal of the assessment was to identify gaps between the District's practices and industry best practices for managing wastewater collection systems. The outcome of this process was a Collection System Assessment Report. Since the completion of the 2003 assessment, the District implemented several of the recommendations and a number of key stakeholders at the District have also changed. The 2006 Collection System Services project updates the 2003 assessment and included high-priority initiatives for immediate implementation focused on sanitary sewer overflow (SSO) reduction and mitigation. These high-priority initiatives included: 1) An Updated Developer-installed Infrastructure Inspection Program and District Outreach to Stakeholders, 2) Standards for Pipeline and Manhole Inspections and Implementation of Contracted Inspection Work, 3) Cleaning Workload Required to Clean the District's Entire System and Implementation of Contract Cleaning Work, 4) Costs, Estimated Flows, and Plausible Systems for Diverting Dry Weather Flows from Streams Through the District's Water Reclamation Plant (WRP), 5) Integrated Computerized Maintenance Management System (CMMS) Scope and Budget for Implementation. In addition to these immediate high-priority actions, to address recent developments and provide for long-term, proactive improvement in the District's wastewater collection system, this project included additional analysis and updating to identify key opportunities for improvement in the following areas: 1. Asset Databases; 2. Collection System Odor Control; 3. Rehabilitation and Replacement capital improvement projects (CIPs); 4. Prioritized Cleaning Program; 5. Lift Station Operation and Maintenance; 6. Regulatory Reporting Practices; and 7. Other Key Opportunities. District staff selected key opportunities from the updated Collection System Assessment Report for implementation over a 5-year planning horizon and an Implementation Schedule was developed based on the priorities set by the District. The plan includes a budgetary estimate of the cost for the implementation of each initiative; including a staffing and equipment plan. This paper presents a summary of the key features of the District's collection system improvement plan to reduce SSOs. As a result of the first year of the program, collect system SSOs have been reduced 27 percent.

Plastic pipeliners have been widely used to rehabilitate our sewer systems. Like all other infrastructure, the long-term performance life should become the most important consideration in the design of pipeliners. In the ASTM F1216 appendix, creep buckling is taken as the controlling failure mechanism for pipeliner design. In current standard practice, a creep modulus is applied in the buckling equation in order to deal with the material creep over the pipeliner's design life. In this paper, based on the original buckling and creep theories, and utilizing previously published as well as recently finished long-term creep experimental data, the authors seek answers to the following questions: a) Is applying the creep modulus in the buckling equation theoretically correct? b) How accurate is the application of a creep modulus in predicting performance life? c) Is there a more accurate and theoretically correct method? d) Are there other critical influences on the long-term performance life of a pipeliner that need to be considered in the design phase?

In a sewage system development project, pipeline construction is the key work owing to pipeline construction shares high cost compared to other works. Furthermore, pipeline construction usually suffers unforeseen site conditions and results in tremendous delays. Identifying potential delay causes is the basis for resolving delay problems before they actually occur. As the budget of sewage systems is increased annually in Taiwan, identifying delay causes and preventing them from occurring are essential for successful sewage system construction projects. Through examining fifteen real cases and validating via a questionnaire survey, this study concluded that moving existed conduits later than planned schedule, unforeseen site conditions and delayed construction planning report approval are the top three significant causes for pipeline construction projects. Identifying the causes is valuable for reference to succeed in future similar projects.

Renewal of aging underground infrastructure is a major challenge that municipalities in North America face every day. Traditional replacement of these underground utilities uses open-cut excavation methods that can be expensive, particularly in built-up areas. In contrast, trenchless technologies use new methods, materials, and equipment that require a minimum of excavation. These new methods are considered much more cost-effective. However, in order to compare methods, engineers and project owners want more data. This article provides a comparison of the estimated costs of the trenchless method known as pipe bursting with the open-cut method for replacing the sewer pipelines in the City of Troy, Michigan. The research found that the pipe-bursting method was much less expensive than the open-cut method. We conclude that using trenchless methods, such as pipe bursting, could save municipalities millions of dollars in the renewal of their of underground utilities systems.

Hurricane Katrina brought the most severe flooding in modern US history, including the submergence of the city of New Orleans, a one million strong major metropolitan area. At present, there are no proven tools for assessing the damage sustained by buried infrastructure networks due to a hurricane or a flood. The paper describes the findings from a fourteen month study of the impact of Hurricanes and other flooding mechanisms on buried infrastructure systems. The study involved the development of an electronic database of detailed pipe damage data collected from six cities along the Mississippi and Louisiana coastal area, detailing the extent and distribution of damages to their buried pipe systems, and involved 25 municipal engineers, administrators, contractors and GIS analysts. A literature review of difficulties encountered during the recovery process in the aftermath of Hurricane Andrew and the 1997 Red River flood is followed by case histories for three Louisiana's cities — Slidell, Covington and Lake Charles (the former two were impacted by Hurricane Katrina while the latter by Hurricane Rita). The paper is concluded with a discussion of non-traditional damage mechanisms associated with hurricanes identified in the course of this study and potential mitigation measures to alleviate their adverse impact on buried infrastructure systems.

The benefits of trenchless technology are well understood by all in our industry — more cost-effective, and less disruptive to streets, driveways, and landscaping. However, what's often less clear to many engineers and city officials faced with a wide selection of materials and processes is just what type of pipe is best suited for a particular trenchless application. This paper will present the engineering considerations involved in selecting thermoplastic pipe for water/sewer directional drilling projects, focusing on assembly considerations, structural and flow performance, pressure-handling capacity, joint integrity, and compatibility with existing systems. These concepts are illustrated by the experiences of Broomfield, Colorado, where trenchless technology was successfully utilized on a modern water reuse distribution system in an area where conventional pipe installation techniques were determined to be unsatisfactory.

With a population of over 680,000 people, the City of Winnipeg is the eighth largest city in Canada. To support this user base the City maintains an inventory of over 2,900 km of water mains, consisting of cast iron (~30 %), asbestos cement (~27 %), PVC (~33 %), and prestressed concrete pressure pipe (~5 %). Historically, the City focused its investment on the replacement and cathodic protection of cast iron mains, which due to highly corrosive soils had experienced extreme deterioration. Consequently, very little was known about the condition of its remaining system, leaving the City exposed to risk and uncertainty over coming planning horizons. Wishing to improve its understanding of material performance and ability to target current and future water system investments, the City worked with UMA Engineering Ltd. to undertake a Water Main Criticality Assessment Study. One component of this project was to undertake an assessment of the City's asbestos-cement (AC) water main inventory. Winnipeg's first AC water mains were installed in 1932, at a time when AC pipe was being introduced to North American markets. Early studies found that they performed well in Winnipeg's aggressive soils, which resulted in widespread adoption and use of AC within the city until the early 1980s. While some work was done to assess the impact of water chemistry on internal pipe wall degradation, very little was known about the long-term performance of the lines, and the risk and liability they might pose. Seeing to address these concerns, an AC Sampling and Testing Program was developed and introduced. Under the AC Sampling and Testing Program, pipe segments were collected opportunistically from in-service water mains throughout the city and subjected to an array of destructive and non-destructive test procedures. Data was collected and analyzed to assess the current risk posed by the City's AC inventory, and to extrapolate long-range system performance. This paper reviews techniques used in the collection and testing of pipe samples, presents findings from the analysis of current and long-term performance, and discusses the challenges faced in introducing a standardized AC sample collection and testing program in the City of Winnipeg.

In September 2006, the City completed the Combined Central Anaheim Master Plan of Sanitary Sewers (CCAAMPSS). This study identified various sewer improvements for existing peak dry weather flows (PDWF) within the central portion of the City to address capacity deficiencies of the sewer system. Approximately $82,241,000 (August 2006 dollars) of sewer improvements for the existing PDWF were identified in the CCAAMPSS. The CCAAMPSS also identified opportunities for alternative alignments that could potentially provide a more cost-effective solution to solving sewer needs. The alternative alignments analysis which included maximizing the performance (capacity) of existing sewer infrastructure led to significant cost savings in capital improvements for the City. Following the completion of the CCAAMPSS, the City proceeded with the design of the alternative alignments for the Group 3 Sewer Design of the Citywide Sanitary Sewer Improvement Program/Projects (CSSIPP). Group 3 of the CSSIPP included the design of sewer pipes found in various sewer models of the CCAAMPSS, including Model 7 and Model 24. Based on approval by the Orange County Sanitation District (OCSD), alternative alignments east of State College Boulevard identified in Model 7 will connect with the OCSD Newhope-Placentia trunk sewer along State College Boulevard. As a result, Model 7 experienced less sewer flow, approximately 1,800 linear feet of improvements no longer needed, and reduced diameters of recommended improvements. This resulted in cost savings of approximately $2,458,000 for capital improvements in Model 7. The sewer design within Model 24 comprised of approximately 5,200 linear feet of new 10- to 15-inch sewer along Santa Ana Street generally between Anaheim Boulevard and the I-5 Freeway. Opportunities to maximize the capacity of existing sewers located near the alignment along Santa Ana Street led to a significant reduction of new sewer needed within Santa Ana Street. The scope of the sewer design reduced to two diversion manholes and only 650 linear feet of new 10-inch sewer. As a result, cost savings in capital improvements were approximately $3,606,000. Overall, the combined savings in sewer improvements in Model 7 and Model 24 of the CCAAMPSS were approximately $6,064,000 as a result of the alternative alignments analysis and the ability to maximize capacity of existing sewers. In addition to incurring cost savings, additional benefits to the City include reduced impacts to existing utilities during construction, reduced disruption to traffic, and a better situation for the City's maintenance of new pipeline infrastructure.

The scattergraph is a graphical tool that provides insight into sewer performance through a simple and intuitive display of flow monitor data. This tool can also be used to determine if the data provided are valid and suitable for further use. Precision and bias are the principle indicators of data quality and together provide a measure of accuracy. These indicators can be evaluated on a scattergraph at human viewing speed by comparing flow monitor data with manual confirmations and a pipe curve based on the Manning Equation. Practical examples from flow monitor locations throughout the United States are provided, demonstrating the scattergraph signatures of both valid and invalid flow monitor data.

A successful private utility project relies on the ability of the Contractor to perform the work on time and within budget. But, when the Contractor declares bankruptcy, where does that leave the owner as well as those impacted by the project? A typical project schedule normally includes some flexibility, but the default of a contract is not a normal factor in a project schedule or a project budget. Construction documents address the termination of the Contractor and the changeover to the Surety, but how do you secure the site for public safety, and prepare the impacted residents for the prolonged construction time? This paper addresses the various construction and design issues faced when a contractor declares bankruptcy, the steps implemented to secure public safety, and the process needed to resolve residential issues. This paper is based on the actual unfortunate events and the lessons learned from such an event.

This paper provides an inspector's view of quality control procedures followed for the repair of the Baltimore Area's Southwestern Transmission Main literally from the "inside out". A 2006 condition assessment of the Southwest Transmission Main which serves Baltimore City, Maryland and several adjoining Counties identified deficiencies that were sufficiently serious that, to avoid a potential catastrophic failure of the main, the engineering consultant recommended that repairs be made before the main was returned to service. A number of reaches of the transmission main which were comprised of 54-, 48- and 36-inch diameter pre-stressed concrete cylinder pipe (PCCP) exhibited significant numbers of pre-stressing wire breaks, longitudinal cracking and delamination of the concrete core. Restoration of service required that three methods of pipe rehabilitation be undertaken: 1) pipe replacement, 2) slip-lining with steel pipe, and 3) lining with a carbon-fiber composite system (CFCS). In Baltimore County, 5,000 feet of 54-inch main was replaced in its entirety with new PCCP, 300 feet of 54-inch was slip-lined and 16 sections of 54-inch pipe were repaired with CFCS. In Baltimore City, 11 sections of 54-inch main were repaired with CFCS. In Howard County 33 sections of 36-inch pipe were repaired with carbon fiber, and in Anne Arundel County, 600 feet of 48-inch pipe was repaired by steel slip-lining, and 8 sections of 36-inch main were repaired using CFCS. This paper provides a perspective from the firsthand viewpoint of two inspectors who were responsible for implementing the quality control procedures that were followed for the repair of 68 sections of 54- and 36-inch PCCP with CFCS. It reviews the methodology employed to conduct quality control inspections of the CFCS repairs, identifies specialized equipment developed for use in the inspections and highlights difficulties that can be encountered depending on the type and size of pipe being repaired. The paper concludes with a review of especially significant inspection procedures, problems and other quality control considerations.

Controlled Low Strength Material (CLSM) is a mixture of fine aggregate, cement, water, and additives such as flyash that is used primarily as bedding and pipe zone fill for pipelines as an alternative to compacted granular fill. The benefits of CLSM are widely recognized as it can provide more effective support to the underside of rigid and flexible pipe, resulting in better quality with less inspection while producing a non-settling fill. Additional benefits of CLSM include: the capability for placement in wet trench conditions, reduced need for trench dams, reduced excavation costs by allowing narrower trenches, and improved worker safety due to reduced exposure. CLSM can be made with commercial aggregate or native soils and can be batched either on-site or off-site. This paper presents four case histories in Northern California where native soils were used exclusively to create CLSM for pipeline backfill. Two projects included trench-side batching of the CLSM, and two projects included central on-site batching of the CLSM with transport to the site in concrete mix trucks. Either granular or fine-grained native soils were used in the CLSM, with one project using lean and fat clay soils almost exclusively. Primary soil constituents, batching methods, and resulting CLSM compressive strength data are presented and discussed for each project. Quality control considerations associated with the use of trench-side material are also discussed.

As the transmission side of the energy industry continues to expand, the demand for larger and longer natural gas and oil pipeline installations has increased significantly. Large diameter HDD pipeline projects are growing in number. But, with any type of pipeline installation, the larger the project, the greater the chance there is of running into problems. More and more pipeline contractors are trying to mitigate potential problems on their large diameter HDD projects by adding a pipe rammer to their job site equipment list in order to react quickly with pipe ramming HDD Assist techniques when problems arise. Several pipe ramming techniques have been introduced that are helping drill operators solve drilling problems and tackle tough conditions. The techniques are changing the way drillers approach projects and respond to problems on the job.

Construction was near completion for a 28 mile long by 48 inch diameter pipeline when problems were discovered in the hydrostatic testing phase. Sections of pipeline would not hold test pressure and subsequent inspections revealed some pipe segments (joints) of the pipeline had collapsed. Additional internal inspections revealed much of the pipeline had excessive vertical deflection and failure of the mortar lining. The authors were hired to provide forensic engineering, pipeline remediation design, construction observation of the pipeline remediation, and construction contract administration. Forensic engineering revealed the primary cause of failure was inadequate compaction of the pipeline embedment material. Approximately 15 miles of the pipeline were completely removed and replaced with new pipe and 13 miles of pipeline were repaired. The pipeline remediation construction cost was approximately $20 million. Many other problems were discovered during the remediation construction and are discussed in the paper. This paper describes the highlights and lessons learned during the forensic engineering phase and pipeline remediation construction phase.

With an aging underground infrastructure and the influence of other factors such as population growth, tighter health and environmental requirements, inadequate inspection and maintenance, and lack of consistency and uniformity in design, construction and operation practices, the performances of underground infrastructure is in very serious condition. It is reported that 70% of Chinese cities do not have the basic data about the underground infrastructure, which frequently results in damage to existing underground infrastructure on the construction job site. The direct and indirect economic loss is estimated up to 6 billion dollars each year in mainland China. In this paper, the authors discuss the present conditions of underground infrastructure in detail, analyze the main factors affecting the performances of underground infrastructure, and put forth some long term methods or efforts which should be taken to ensure the sustainability of underground infrastructure in mainland China.

Many owners of Pre-stressed Concrete Cylinder Pipe (PCCP) water mains around the world experienced failures in their pipelines. The condition and performance of any water pipelines can be assessed by conducting direct inspection (electromagnetic, acoustic monitoring, GPR radar, etc), which when applied to an entire pipeline can be prohibitively expensive or impossible due to operating conditions. As an alternative, it is possible to use intelligent models to predict the condition and performance assessment of the pipelines based on historical condition observations and inspections results. In this research work, a PCCP wire breaks prediction model is developed using Artificial Neural Network (ANN) technique and applied to real-world acoustic monitoring data collected from Great Man-made River Project (GMRP). The developed model involves nine input variables that affect the deterioration process of PCCP. These variables are: monitoring period, pipe age, soil resistivity, design pressure, design soil density, design soil cover, type of pre-stressing wire wrap, wire diameter and wire pitch. The output of the model is the number of wire breaks, which is considered the most important factor in evaluating the condition and performance of PCCP. The ANN model demonstrates well representation to the training patterns and shows good prediction performance ("R²"~0.99 for groups of Special Pipes and "R²"~0.60 for groups of Standard Pipes). The results of ANN model are compared with that of Multiple Linear Regression (MLR) model ("R²"<0.28 for both Special & Standard groups of pipes).

The City of Lake Worth and Palm Beach County (FL) share operating ownership of a 14.1 mile wastewater regional force main (RFM) serving six additional municipalities and over 475,000 residents. Installed in 1972–79, the FM extends from the Master Pump Station within Lake Worth 4.45 miles as 36" pre-stressed concrete cylinder pipe (PCCP) and from the city limits 9.65 miles into the county as 42" – 54" ductile iron pipe (DIP) terminating at the East Central Regional Water Reclamation Facility (ECRWRF) within the City of West Palm Beach. Flow is characterized primarily as domestic and commercial with an average daily flow (ADF) of 20 MGD; pressure averages 20–25 psig with periodic peaks of about 45 psig. Because the RFM is manifolded it serves as the primary conduit of wastewater to the treatment plant — there is are no redundant or bypass lines to resort to if the line fails, it cannot be taken out of services for more than a few hours, and incoming flow would be forced to spill to an ocean outfall. Recent failures of the DIP portion resulting in spills and regulatory action from FL DEP heightened the awareness of the served jurisdictions of the potential for a catastrophic failure and led to an investigation of the integrity of the entire line. Defects that included deterioration of the pipe crown and at joints were found in 48" pipe along with a failure in an adjoining 16" line which ultimately ties into a 30" force main that connects with the RFM. Using state-of-the-art assessment technologies including ultrasonic and broadband electromagnetic (BEM) scanning, measurements were made of the existing DIP thickness including a profile of the wall at selected locations. Similarly, acoustical emission technology (AET) was applied to the PCCP segments to "listen" on active distress signals from tensioning wires stretching or breaking within the pipe wall. Using historical operating and maintenance records and a field study of air release valves, a determination was made regarding useful life of the pipeline, likely failure points, remaining wall thickness of the DIP segments, and what areas should be rehabilitated or replaced. A phased program "renewal" was then developed for the RFM to be implemented by Lake Worth and the Palm Beach County Water Utilities Department.

Hampden Township (Township) is a growing municipality in central Pennsylvania. As with many communities, the Township continues to battle the problems associated with excessive infiltration and inflow (I/I) into its sewer system. The sewer system assets are critical to the continued operation of wastewater collection, conveyance and treatment. In order to implement a sewer system asset management system and address the I/I concerns, the Township initiated investigation and assessment techniques. In 2002 the Township adopted an aggressive I/I Removal Program (Program), dedicating nearly 10 percent of its annual operating budget to the removal of I/I. A flow meter study conducted prior to the start of the Program was used to generally identify areas of the Township with significant I/I. This flow meter study was also used as a bench mark to measure the success of the Program. Based on the findings of the flow meter study, a portion of the Township was selected for the Program's initial five-year pilot study. The first steps of the Program included identifying and prioritizing sources of I/I. The Township utilizes two (2) television inspection trucks to inspect mainline sewers and lateral connections. In the initial five-years of the Program the Township televised over 200,000 feet of mainline sewers and more than 1,000 lateral connections. Major collection system components were assessed. Defects observed during these inspections were recorded with WINCAN software and stored in the Township's GIS database along with flow data which was continuously recorded at the Township's pumping stations and five open channel flow meters. The Township also took weir readings where significant sources of I/I were observed. Members of the Township's maintenance staff are certified by NASSCO in the Pipeline Assessment and Certification Program (PACP). PACP is a standardized format to evaluate internal television inspections of sewers. Visual defects are identified utilizing key structural and O&M parameters. Standard defect coding is a key component of the program. Using the NASSCO rating systems, the Township defined the scope of two major rehabilitation projects. A variety of trenchless technologies were utilized during these two projects. Methods of rehabilitation included cured-in-place lining of sewer mains and laterals, fold-and-form lining of manholes, epoxy coating of manholes, and cured-in-place manhole lining. In addition to the two rehabilitation projects, Township staff also air tested and grouted more than 900 joints and performed numerous spot repairs.

On May 16, 2006, the Water Authority experienced a failure on the 66-inch diameter Pipeline 3 in Mission Trails Regional Park. The failure of Pipeline 3 also impacted Pipeline 4, prohibiting the delivery of all untreated water to three water treatment plants. An emergency contract was awarded to repair the damage at the site and to restore untreated water service. A 30-inch interconnection pipe between P3 and P4, two miles south of the break, restored 70 percent of the untreated aqueduct system capacity to the one million residents in the southern third of the county. The Water Authority prepared an action plan to restore capacity to customers affected by the break on P3. In July 2006, the Water Authority advertised a design-build contract to expedite construction of a 72-inch by 72-inch crossover in Jackson Drive. The selection was based on a combination of qualifications and price. The crossover pipeline was ready for water delivery by October 28, 2006. The break on P3 taught the Water Authority valuable lessons in pipeline condition assessment, emergency response, site restoration, design-build during a declared emergency, and the need to accelerate future pipe rehabilitation projects.

The Chattahoochee Raw Water Transmission Mains for DeKalb County provide the entire water supply for over 750,000 residents in the Atlanta, Georgia area. The pipelines are along a 13,000 foot easement from the pumping station on the Chattahoochee River to the new Scott Candler Water Filtration Plant on Winters Chapel Road. The existing pipelines were installed in three phases, in 1942, 1960 and 1980. A new 72-inch diameter pipeline was planned to replace the two older mains, to alleviate the issues of pipe transient damage, reliability and capacity. Detailed transient analyses of the existing pipe network (30", 48" and 60") confirmed the location of significant surge pressures, both positive and negative, and correlated with the evidence of breaks in the field. A pipeline was required that would reduce this surge potential, for both current flows of 140 mgd and for the ultimate pumping capacity of 300 mgd. An analysis of pipeline sizing to reduce transients, and to optimize pumping head, led to increasing the new pipe from 72-inches to 96-inch diameter. Through proper sizing of the transmission main, operating costs will be reduced to their optimum level, and the savings will offset the incremental cost of the larger pipeline. This paper provides a summary of the analyses, and how this approach can be applied for optimizing pipe selection for major transmission mains.

Water systems operation and management has benefited from the widespread use of Geographic Information Systems (GIS). Several studies had been developed relying on GIS data in order to predict breakage rates and remaining service life of pipes. The application of spatial analysis methods in areas such as epidemiology and crime analysis has provided a better understanding of the spatial interdependencies in the distribution of phenomena in space. Similar benefit is likely to be obtained for water distribution breakage studies. The goal of this paper is to present the preliminary results of a study of the use of GIS for the analysis of breakage data taking into consideration the spatial interdependencies of breaks points. More specifically, we will present the issues for data preparation, integration and exploratory analysis, and investigate the usefulness of GIS spatial analysis capabilities for the assessment of failure patterns and trends in water distribution networks.

On October 31, 2006, the Homestake Pipeline experienced a catastrophic failure. This 66-inch (1680 millimeter) diameter, 46-mile (74-kilometer) long, prestressed concrete (non-cylinder) pipeline (PCP) traverses Colorado's mountains and provides roughly 60 percent of the raw water for the Cities of Aurora and Colorado Springs. The Homestake Water Project, operator of the pipeline, had completed the first year of inspection in a multi-year condition assessment program and this inspection had stopped approximately 1 mile short of the future failure site. The failure occurred on the PCP at the transition point between steel and PCP pipe. The nature and apparent cause of the failure provide insight to potential vulnerabilities at similar transition points on the Homestake Pipeline and the importance of circumferential cracking in non-cylinder pipelines. The potential for failures at joint end-areas, which are "blind spots" for electromagnetic inspection, suggest caution be used when drawing conclusions from such inspections. The failure cause and the subsequent repair modified the planning for the subsequent years of condition assessment and resulted in a revised repair spool configuration and repair procedure.

In many American cities, especially those with a widely dispersed, fast-growing population, light rail transit (LRT) has become an increasingly popular transportation alternative, offering a way to relieve congestion, prepare for future growth, and in some cases spur a downtown revitalization. Twenty U.S. municipalities, including Boston, Philadelphia, Baltimore, Washington, DC, Minneapolis, Houston, San Jose, Denver, Dallas, Portland (Oregon), Sacramento and Los Angeles, have put new LRT systems into operation since 1960. Another 37 cities have LRT systems planned or in the works, according to the American Public Transportation Association (APTA). For pipeline operators in those areas, this means new operational and safety concerns, including the risk of stray-current corrosion.