Stormwater Quality Design Manual (May 2007) - City of Sacramento ...

Technical RequirementsVegetated SwaleTable VS-2. Inspection and Maintenance Recommendations for Vegetated SwalesActivityMow grass to maintain a height of 4 to 6 inches or above depth of flowat WQF.Use integrated pest management (IPM) techniques to minimize use offertilizers, pesticides and herbicides.Remove trash and debris from the swale (especially the outlet)Inspect swale for signs of erosion, vegetation damage/coverage,channelization problems, debris build-up and excessive sedimentationin bottom of channel. Correct problems (e.g., remove sediment orstabilize, re-seed eroded areas) as soon as possible.Remove sediment in inlet areas, channel, culverts, and outletswhenever flow into the swale is retarded or blocked.Repair ruts or holes in the channel by removing vegetation, adding andtamping suitable soil, and reseeding. Replace damaged vegetation.Inspect swale for obstructions (e.g., debris accumulation, invasivevegetation) and pools of standing water that can provide mosquitobreedinghabitat. Correct observed problems as soon as possible.Reconstruct or replace the control measure when it is no longerfunctioning properly.ScheduleAs needed to maintain optimum grassheightAs neededAs neededAt least twice annually. Schedule oneinspection at the end of the wet season sothat summer maintenance can bescheduled to prepare swale for wetseason. Additional inspections afterperiods of heavy runoff are desirable.As neededAs neededAt least twice during the wet season aftersignificant storms. Additional inspectionsafter periods of heavy runoff are desirable.See projected lifespan in Appendix B forinformational purposes.Stormwater Quality Design Manual for the Sacramento and South Placer RegionsVS-6 May 2007