You are here:
DECISION SUPPORT TOOLS FOR MANAGING WASTEWATER PIPELINE PERFORMANCE IMPROVEMENTS
Citation:
Tafuri*, A. DECISION SUPPORT TOOLS FOR MANAGING WASTEWATER PIPELINE PERFORMANCE IMPROVEMENTS. Presented at WEF 2001 Collection System Odyssey: Integrating O&M and Wet-Weather solutions, Bellevue, WA, 7/8-11/2001.
Description:
Wastewater collection systems are an extensive part of the nation's infrastructure. In the US approximately 150 million people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately owned service laterals connecting building to sewer mains). As these systems become older, more preventive maintenance and renewal are required. For municipalities to cost-effectively plan, organize, and implement this effort, they require improved information on strctural conditions, decision-making tools, operation and maintenance (O&M) practices, and techniques for repair and rehabilitation. Experiences with exemplary European wastewater collection systems are potential sources of novel and efficient maintenance and renewal practices. Although a lot of money has been spent trying to increase the knowledge about the structural condition of wastewater infrastructure, our knolwege is still very limited. Pipe age is a factor; however, it is usually a combination of several factors that causes failures and influences maintenance decisions, making the situation very complex. To effectively manage maintenance and rehabilitation programs, managers need a quantitative picture of the condition and performance of their systems. Conceptually, this quantitative picture can be generated through the selection of performance indicators (e.g., overflows/year/mile), followed by collection of the required data (e.g., overflows/year, miles of sewer), and computation of the performance indicator value (e.g., 0.3 overflows/year/mile). Performance indicator trends can be used to monitor conditions and performance within a system over time (e.g., increase in overflow rate over last 5 years) or over space (e.g., sub-system X overflow rate if 75% greater than sub-system Y) and between separate systems (e.g., system A overflow rate is 50% higher than "similar" system B). Managers can use these indicators to identify, quantify, and justify areas requiring increased or decreased labor emphasis. There have been several attempts, both here and abroad, to develop and apply performance indicators; however, benefits and associated costs of using them have not been well documented. This paper will discuss procedures to optimize the O&M of wastewater collection systems, including European aproaches for diagnosing and analyzing systems, and in particular the use of non-hydraulic models for predicting failures in wastewater collection systems.