Journal of Water Resources Planning and Management

Significant levels of water conservation can be achieved through control of leakage from a water distribution system. One of the best means of determining the level of water conservation which can be achieved is by conducting a complete water audit. The volume of water which can be conserved through a leakage control program may exceed the level of conservation available through the use of consumer oriented water conservation devices. A complete water audit generally consists of three phases. These are master meter testing, leak detection and quantification, and system inventory. However, the scope of water audits is often varied in order to meet an individual community's needs. Six case histories of successful water audit/leakage control programs are presented. These programs resulted in water savings ranging from approximately 12% to as high as 75% of the average daily pumpage.

Ice jams are a major cause of flooding. Little has been done to develop methods for economic analysis of ice‐related flooding. Since the economic feasibility of a project is generally based on damages prevented, reliable estimates of expected annual damages are necessary for efficient allocation of scarce resources by decision makers. Estimation of expected annual damages under ice conditions is a complex problem because up to three different sets of hydraulic conditions must be accounted for. Expected annual damages can be estimated by assigning probabilistic weights at various points in the computation of these damages. Estimates of these weights, which are very sensitive to simplifying assumptions must be made in the analysis.

Developing a public involvement program and determining what procedures and methods are effective in water resources planning are described. Analysis is based on experiences in the development and management of a U.S. Army Corps of Engineers Public Involvement Program as part of a flood control project. Guidelines from previous efforts are identified as they relate to the goals of: (1) Involving the public in a study; and (2) meeting the objectives of a study. The public involvement program used such methods as a Delphi panel, public meetings and workshops, public information fact sheets, media contacts, and information packets. These methods were used in identifying water‐related problems and evaluating alternatives to those problems. Methods should be carefully selected, focusing on program purpose and expectations. The flexibility of a public involvement program should also be a major consideration, to allow for change as a study progresses.

The interrelations of water use, population growth, and urbanization in the state of Florida are examined. Although the greatest freshwater use is for irrigation, the paper focuses on municipal use because of its projected increase and because it suffers the greatest problems in times of water shortage. Population and municipal water use trends, by county, show the greatest growth in South Florida coastal areas. Projections of water use to the year 2000 follow a similar pattern, with increased urbanization placing growing demands on water. Important policy issues are the ability to provide for future needs and the effectiveness of public policy for dealing with the interrelations of growth and municipal water use. Existing state laws and policies are reviewed, and their adequacy for handling future needs with respect to water use are considered. Water supply policy is being well served by the state's water management districts, but additional efforts must be placed on planning for municipal water shortages.

The use of irrigation systems in the humid east has traditionally been minimal due to frequent rainfall. The argument most often encountered against the use of irrigation in humid regions is that the return on investment is negligible. A general frequency‐based procedure for evaluating alternative policies that maximize irrigation net benefits is presented. The method accounts for the random nature of rainfall events and their obvious impact on crop yields and irrigation costs. The structure of a deterministic hydro‐economic model is described and applied to long‐term daily climatic data in order to evaluate alternative irrigation in humid regions. The question of economic feasibility is addressed in terms of net benefit analysis procedure. The sensitivity of the model to variable irrigation costs is also examined.

Many considerations exist when attempting to manage a groundwater system that flows across interstate boundaries. The legal, institutional, and technical constraints managing one such system, the Coastal Plain Aquifer System of the Delaware River Basin, are described. A ground‐water management plan aimed at addressing the two biggest threats to the quality of the interstate aquifer system, synthetic organic contamination and salinity intrusion, is presented. The recommended plan includes provisions for locating future ground‐water withdrawals away from stressed areas; developing a surface water supply as part of a conjunctive use scheme; and developing new well fields in the phreatic portions of unstressed areas. The plan also contains a set of policy recommendations aimed at addressing legal and institutional problems.

Flood‐plain delineation in ice jam prone regions is in its infancy. A methodology is introduced for incorporating the risk of ice jams into flood‐plain delineations in northern regions of the U.S. The distribution of flood elevations is derived from the marginal probability distributions for ice cover and storm induced (non‐ice) flood elevations. An application indicates that incorporation of the hydraulics of an ice cover into flood‐plain delineations can result in substantial increases in the inundation levels which generally implies a significant increase in the lateral extent of flood‐plain boundaries. These results document the need to consider the probability of ice jam flood events in the computation of annual maximum flood elevation distributions and flood risk in ice jam prone regions.

AS water becomes relatively more scarce and as the cost of developing new sources of water increases, projects designed to reduce the quantities of water consumed (i.e, demand management projects) become more attractive alternatives to supply augmentation projects. A framework is presented that allows planners of water supply systems to make efficient use of water resources by explicitly considering the management of the demand for water as a supplement to traditional supply augmentation projects. The framework includes a dynamic programming algorithm to determine the optimal combination of supply augmentation and demand management projects. Two optimization criteria are considered: (1) Minimization of the present value of the cost of implementing the projects; and (2) minimization of the expected value of the costs to cope with emergencies in the supply of water. The tradeoffs between the two objectives are examined through the development of the set of noninferior solutions using the Non‐Inferior Set Estimation method. The applicability of the framework is illustrated in a case study involving the Santa Clara Valley Water District in Santa Clara County, California.

The Corps of Engineers has proposed and analyzed the effects of diverting Lake Michigan waters down the Illinois River in times of above average lake levels. Effects would vary considerably depending upon the rate and timing of diversion. Major benefits on the river portion will be an improvement in water quality, increased benefits to commercial navigation and increased power generation. On the Great Lakes the major benefits would be reduction in shoreline erosion and flooding. Adverse effects would be significant. On the river major adverse effects are due to increased flooding over existing conditions and longer flooding duration in the lower reaches. Current trends of habitat destruction and loss of species diversity in natural ecosystems will be accelerated by the increased diversion, resulting in the deterioration of natural ecosystems. Managed ecosystems such as leveed farmlands and duck clubs will suffer higher drainage costs as a result of the increased flooding. Unleveed areas will experience substantial crop losses, especially in low water years, and diversion may ultimately preclude agriculture in such areas. On the lakes, major adverse effects would result from power loss, lowered ship capacity resulting from shallower draft at docking facilities, and loss of water‐edge ecosystems.