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Last Updated: Thursday, January 5, 2012 1:08 PM

Wet Basin

This wet basin has a permanent pool of water surrounded by a variety of wetland plant species. Biological processes, such as nutrient uptake by plants, may aid in reducing the amount of soluble nutrients. The permanent pool is maintained by a continuous flow of diverted urban runoff. Stormwater is diverted to the pool where it inundates the surrounding vegetation. The co-mingled water is discharged until the water level returns to the level of the permanent pool. Sediment, nutrients, and particulate metals are removed from stormwater by settling particles and associated pollutants to the bottom of the basin. After each storm, the basin is checked so that a drain-down time of 24 hours to the permanent pool level is not exceeded.

The pool is inspected monthly and maintained to prevent erosion, or leakage. The perimeter of the pool is also inspected for use by endangered, threatened, or special concern species. Vegetation must be managed to allow enough space for mosquito fish to remain effective for mosquito control. If necessary, sediment, debris, and excess vegetation are removed when the basin is drained for vegetation removal.

JUNE 1999

  JUNE 2000  

Site Location: I-5/La Costa (east)

Directions: I-5 to eastbound La Costa Blvd., south on Piraeus Street, on corner of Piraeus Street and La Costa Avenue


Division of Environmental Analysis, Stormwater Unit
California Department of Transportation
P.O. Box 942874, MS-27
Sacramento, CA 94274-0001
Email: Division of Environmental Analysis, Stormwater Unit