5.8.5 Regional Infiltration

ProjectGleason Lake Regional Infiltration
DescriptionImplementation of opportunities to increase infiltration, including but not limited to construction of infiltration basins and devices, wetland restoration, reforestation, revegetation.
Need

The proposed rule requiring new development and redevelopment to infiltrate one inch of rainfall would capture approximately 70 percent of new runoff volume from the watershed. The remaining 30 percent would continue to convey pollutants to Gleason Lake and other resources in the watershed. To minimize this pollutant loading and to minimize new stormwater volumes generated from the subwatershed, regional infiltration opportunities such as wetland restoration, underground storage and infiltration, or native vegetation restoration and reforestation may be necessary.

Prior to implementing any of these options, opportunities in the subwatershed should be investigated for the most cost-effective and suitable locations. Regional infiltration will be focused on those subwatershed units that are expected to see significant new runoff volumes between 2000 and ultimate development.

OutcomeMinimized new pollutant loads conveyed by new runoff; minimized new volumes generated by new development; prevention of potential future stream and channel erosion; protection of stream base flows and wetland and surficial groundwater hydrology; wetland restorations; conservation of high-value native vegetation and habitat.
Estimated Cost and Funding

Project 1: Improvements in GLC-4. Funding source is District capital levy.

Project 2: Improvements in GLC-9. Funding source is District capital levy.

$179,700

$32,900

Schedule

2009: Identify and construct improvements in GL-4

2012: Identify and construct improvements in GL-9