It is recommended that at a minimum, the drainage performance of stormwater infiltration BMPs be evaluated as part of Assumption and Verification inspections. Drainage performance, or the ability of the BMP to fully drain runoff from a certain size storm event within a certain time period, can be evaluated by continuous monitoring during natural or simulated storm events. When a water source of sufficient size to fill the sub-surface water storage reservoir is available, it is recommended that drainage performance evaluations be performed by simulated storm event testing as results can be produced within a much shorter time period (e.g., within a week) as opposed to natural storm event testing, which can require field monitoring activities over 6 months to 2 years in duration. | It is recommended that at a minimum, the drainage performance of stormwater infiltration BMPs be evaluated as part of Assumption and Verification inspections. Drainage performance, or the ability of the BMP to fully drain runoff from a certain size storm event within a certain time period, can be evaluated by continuous monitoring during natural or simulated storm events. When a water source of sufficient size to fill the sub-surface water storage reservoir is available, it is recommended that drainage performance evaluations be performed by simulated storm event testing as results can be produced within a much shorter time period (e.g., within a week) as opposed to natural storm event testing, which can require field monitoring activities over 6 months to 2 years in duration. |