BEsT MANAGEMENT PRACTICEs HANDbooK - Tahoe BMP

4.3.1.3 STORM DRAINAlternative Names: Subsurface Drain, PipeBMP DESIGN APPROACHPollutant SourceControlHydrologic SourceControlStormwater TreatmentSCALE OF APPLICATIONAll SFR and MFR < 1acreMFR 1-5 Acre andCICU < 5 acresMFR and CICU > 5acres and all WQIPsTYPE OF APPLICATIONTemporaryPermanentStorm drain inlet conveys water to a subsurface storm drain.DESCRIPTIONA storm drain is a pipe or other conduit used to collect and convey surfacerunoff from paved streets and parking lots to a stable discharge point,preferably a treatment and/or infiltration facility. In the Lake Tahoe Region,municipal stormwater drains are separate from sanitary sewer systems, and, as aconsequence, stormwater is commonly not treated and may be discharged toStream Environment Zones (SEZs) or to Lake Tahoe. This section deals withunderground storm drains only, refer to Section 4.3.1.8, A/C Swale, or4.3.1.10, Rock-lined and Vegetated Swale for more details regarding openchannels.Storm drains alone have no water quality benefit and tend to increasestormwater runoff velocity and erosion potential at discharge locations.However, in a developed watershed they are often a necessary component of adrainage and treatment system that as a whole improves water quality.APPLICABILITYStorm drains are applicable to sites with curb and gutter systems, drainageways, and other small runoff collection structures; however, they are mostcommonly installed on a neighborhood scale in densely-developedcommercial/residential areas.TRPA BMP HandbookChapter 4: BMP Toolkit2012 4.3.1.3-Storm DrainPage 1