How to Maximize Effectiveness of Your MS4 Stormwater Program by Using Risk-Based Stormwater Asset Management

Water and wastewater systems typically have dedicated funding sources to address system issues while stormwater systems for most communities/agencies are typically addressed from a General Fund. Identifying and choosing the most cost-effective approach to stormwater management can be a struggle. Risk-based asset management is quickly becoming a preferred business process for municipalities, and Departments of Transportation (DOTs) who are required to perfom asset management to be eligible for MAP-21 funds. It helps prioritize capital investments throughout a stormwater system and meet service and performance expectations of customers and regulators while protecting the environment and ensuring public safety.This paper describes how principles of risk-based asset management, consistent with the Water Environment Research Foundation’s (WERF’s) Strategic Asset Management (SAM) Implementation and Communication research program, may be adapted for obtaining stormwater asset data, performing data analysis and risk reviews, and developing a risk-based cost-effective stormwater asset management program. Case studies for both transportation and Municipal Separate Storm Sewer System (MS4) related programs including New York City, Washington DC, Chesterfield County, Virginia and the Georgia Department of Transportation are provided.A risk-based approach to stormwater system asset management can help communities and agencies inventory their assets, determine the current physical state and performance capabilities of each asset, establish its probability of failure and its consequence of failure, and lead to a cost-effective prioritization of future capital investments.