AWWA JTMGT64452

With increasing federal regulations on storm water management, utilities now have to manageboth the quantity and quality of storm water runoff that occurs from developed and undisturbedland. This challenge is particularly acute for utilities that have a legacy combined sewer system,which conveys both storm water and sanitary sewage to the treatment facilities. On normal flowconditions, the combined sanitary sewer system functions well in conveying the combined flowsto the treatment facilities. However, in times of heavy rainfall, due to the excessive storm waterrunoff, the system carries flows that are in excess of treatment capacity. When such situationsoccur, the combined sewer system triggers a Combined Sewer Overflow (CSO), wherein aportion of the untreated flows are directly diverted to surface water streams, bypassing treatment.The CSOs significantly impair downstream surface water quality, endangering aquatic life whilealso posing a health hazard. To mitigate CSOs, Municipalities that have legacy combined sewersystems typically develop and implement CSO mitigation plans. Successful implementation ofCSO mitigation tasks requires significant financial investments. Therefore, municipalities withcombined sewer systems have a greater need to not only aggressively manage storm water runoffbut also to develop a financing mechanism to meet the investment and operational needs of CSOmitigation.This paper describes a three-phased framework that municipalities with a legacycombined sewer system can utilize to develop a storm water user fee program. The frameworkfacilitates the determination of storm water revenue requirements, and the development of anequitable and defensible storm water user fee. The framework and the illustrative valuespresented are based on the storm water user fee that was developed recently for the City ofWilmington, Delaware.The framework described here is applicable not only to municipalities that have a legacy ofcombined sewer infrastructure, but also to any utility that maintains a combined water/sewerenterprise fund, without delineating a distinct chart of accounts for storm water operations. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

02/01/2007

Number of Pages:

8

File Size:

1 file