Costs and Benefits of Storm-Water Management: Case Study of the Puget Sound Region

Abstract

With rising expenses and scrutiny of storm-water programs, managers need information on costs and benefits to make rational funding decisions. Most, however, lack this basic information. This study sought to identify and quantify the economic and ecological costs of storm-water-related damage and storm-water-management programs, and to understand relationships between management activities and damage reduction. Data were collected from published agency budgets, damage assessments, and structured interviews with storm-water managers. We focused on a single region, the Puget Sound region of Washington State, where storm-water issues abound and annual storm-water expenditures average about $100/capita. Benefits of storm-water management, primarily avoided damages, were presumed to exceed expenditures, but most jurisdictions have not systematically evaluated program effectiveness. Moreover, ecological damage from storm water is significant but commonly neglected in funding decisions. Results indicate the need to (1) evaluate the effectiveness of storm-water-management expenditures; (2) consider nonmonetary and ecological impacts in management and funding decisions; (3) explore preventive measures that can be less costly than remediation; and (4) increase public awareness of storm-water problems to support objective funding decisions.