GIS: A Decision Making Tool for Pipeline Asset Management in Atlanta

Abstract

The City of Atlanta has had a Sewer System Evaluation Survey (SSES) program underway since 2001. This program involves the inspection of the nearly 1580 miles of sanitary and combined sewer which includes all pipes of diameters less than 24”. The program uses a variety of techniques such as CCTV, dye and smoke testing, flow and rain monitoring. The data is used as the basis for determining where repairs, rehabilitation, upsizing or sewer replacement are needed. As this program draws to a close, Atlanta will continue to rely on this comprehensive set of information to make the tough decisions regarding allocation of limited financial resources for the future maintenance of its sewer system. This paper focuses on how Atlanta uses Geographical Information Systems (GIS) for Quality Assurance/Quality Control (QA/QC) of its SSES data, and how GIS is used to enhance the development of intelligent decisions with regards to both water and sewer system pipeline capacity upgrades and pipeline rehabilitation and replacement. These decisions will be at the core of Atlanta’s Asset Management Program. The City of Atlanta, Department of Watershed Management (DWM) has developed a robust process for the evaluation of SSES data. While the ultimate repository for this condition assessment data is the Hansen computerized maintenance management system (CMMS) software system, GIS plays a critical role in providing the spatial component and aid the QA/QC process. Additionally, GIS is used to develop maps of sewer system overflows and other events that provide information on system capacity and conditions. This paper will explain how GIS is used for the correlation of data from multiple sources (flooding, overflows, spills, pipe failures, aerial segments, customer complaints) and its contribution in on-going system maintenance efforts and capital programs. Development of a robust and sustainable long-term Asset Management Program for pipelines requires the ability to present knowledge about a systems condition to senior management using mechanisms that are data driven, and yet easily accessible. Options for extending the use of GIS functionality in various ways will be explored. Finally, the paper will draw conclusions on how to use these processes for decisionmaking in drinking water pipe system asset management. The DWM is currently engaged in an effort to locate, identify, operate and assess its drinking water valves and hydrants. The potential for sharing knowledge gleaned from the SSES experiences will be explored.