Identifying Appropriate Means and Methods for Locating Buried Utilities

Subsurface Utility Engineering (SUE) is increasing in use and becoming a standard process during the planning and pre-engineering stages of a project. Studies performed show a savings benefit on projects that employ either designating or locating activities vs. the traditional one-call approach. Most of the technologies associated with these activities are used throughout the world routinely; however, the choice on which technology is appropriate for a single project is difficult. Currently, the decision is made almost entirely on a person's prior experiences and not so much as a standard process based on facts and data. Research has been done to quantify which ASCE Quality Level is most closely associated with a project based on the level of risk as determined by the amount of known and unknown information (such as utility type, depth, and material). But, after a quality level is determined there is a lack of direction on which technology or method is best suitable for locating utilities for a given project. The research presented in this paper is aimed at producing a decision support tool that will aid persons such as state department of transportation officials, consultants, and whoever else is responsible for utilities on a project. The tool developed consists of two evaluations designed to collect information about how a locating technology operates, its' limitations, data produced, and associated costs. The Performance Evaluation and the Economic Evaluation are filled out for various pieces of equipment and then, in conjunction with the project information sheet, compared to determine the most suitable method for finding buried assets on the project site. The performance evaluation takes into account factors such as soil type, environmental conditions, proximity and type of nearby structures, amount of training required to perform the testing, and material properties of the utility. Field demonstrations are on-going with consultants, municipalities, and State DOTs to further evaluate the tool's effectiveness and refine how the information is presented to the user. The final goal of the research is to take the data gathered and combine it into an interactive tool that can be used to determine a suitable technology to use to locate buried assets while minimizing cost and keeping the quality of data at the desired level. The process can also be used as a training tool for field and office personnel to familiarize themselves with the available technology and its' limitations.