Urban System

The District's local storm water drainage system consists of storm drains, detention and retention basins, and pump stations. The system is designed to retain and infiltrate as much stormwater and urban runoff as possible. The District's Storm Drainage and Flood Control Master Plan includes 161 drainage areas, each providing service to approximately one to two square miles. All but five of the developed drainage areas are served by a retention or detention facility. Click here to see all 161 drainage areas and the basins and pipeline that serve them.

Stormwater flows into storm drain inlets, and through a network of pipes to a nearby ponding basin. Here the water is stored to protect neighborhoods from flooding and to replenish the groundwater aquifer, which is the primary source of our community’s drinking water. The diagram below right shows the secondary use of basins as recreational facilities.

Local drainage services include topographic mapping, Master Plan engineering and facility design; system construction, operation, and maintenance; and engineering design services to ensure adequate drainage for new development. Click here for more information on the storm drainage system.

Funding for local drainage services comes from fees paid with new development. Each year drainage fees are updated to keep pace with cost changes in construction and land acquisition. Click here for more information on the annual drainage fee update.