Using P8 to calculate load reduction and WLA reporting terms Using P8 to calculate load reduction and WLA reporting terms

Using P8 to calculate load reduction and WLA reporting terms
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Reporting term	Infiltration/sedimentation BMPs	Filtration BMPs
Pollutant Removal and Outflow Concentration Calculations
Applicable P8 Removal Terms	(03) Infiltration; (08) Sedimentation + Decay	(05) Filtration Removal; (08) Sedimentation + Decay
Pollutant removal	(09) Total Inflow - (10) Surface Outflow	(09) Total Inflow -(12) Total Outflow
Outflow Loading** (for outflow concentration summary)	Surface outflow	Total outflow
Watershed and Areal Loading Calculations
Directly contributing watershed area to a device (acres)	Sum of all watersheds routing directly to BMP device
Cumulative contributing watershed area to a device (acres)	Directly contributing watershed area + Directly contributing watershed area of all upstream devices
Watershed pollutant areal loading at device (pre-treatment) (lbs/acre/year)	[(01) Watershed Inflow (lbs)] / [Directly Contributing Watershed Area (acres)] / [Simulation Duration (years)]
Pollutant areal loading from device (post-treatment) (lbs/acre/year)	[Outflow Loading** (lbs)] / [Cumulative Contributing Watershed Area (acres)] / [Simulation Duration (years)]
Watershed pollutant areal loading model wide (pre-treatment) (lbs/acre/year)	[Sum of (01) Watershed Inflow at all devices (lbs)] / [Total Model Watershed Area (acres)] / [Simulation Duration (years)]
Model Wide Outflow*** (lbs)	[Sum of (01) Watershed Inflow at all devices (lbs)] - [Sum of (Pollutant Removal*) at all devices (lbs)]
Pollutant areal loading model wide (post-treatment) (lbs/acre/year)	[Model Wide Outflow*** (lbs)] / [Total Model Watershed Area (acres)] / [Simulation Duration (years)]