Placer County has initiated maintenance of the treatment BMP within West Sunnyside on an as-needed basis based on the results of the required condition assessments described above (The 2017 BMP RAM score was a 4.6 so no maintenance was needed). Essential, key and supporting BMPs are maintained by the Placer County street maintenance crew or equivalent by vactor truck, backhoe, and/or hand crew or other method necessary to remove excess sediment from the BMPs and restore infiltration/filtration function. Emphasis is placed on restoring the infiltration capacity of the soil in the basins or infiltration features and restoring filtration capacity of the cartridge filters. BMP Ram score of 2 or less is a high priority maintenance need, 3 is medium need and 4-5 is low priority.

Placer County plans to and has been inspecting all key and essential treatment BMPs including the one in West Sunnyside in accordance with the protocols described in the BMP RAM User Manual V2 (2NDNATURE 2015) or acceptable equivalent method as required by the NPDES permit. Inspections of all BMPs take place annually during spring, summer, or fall. Benchmark and threshold values for BMP condition are set in BMP RAM. In BMP RAM, the infiltration observation for dry basins and infiltration features offers a “User Defined” method. The California Stormwater Quality Association (CASQA) BMP Fact Sheet on infiltration basins suggests inspecting the basins 48 to 72 hours after a storm event to determine that all water has infiltrated. If all water has not infiltrated during this time period, maintenance should be performed. Placer County has been reviewing the infiltration capacity of dry basins using both the CASQA suggested method along with CHP.