Using WinSLAMM to generate load reduction and WLA reporting terms
Link to this table
|Reporting term||Individual BMPs ("Junctions" summary tab)1||Model-Wide summary ("Output summary" tab)|
|Pollutant Loading: TSS, TPP, and TDP|
|Watershed Loading* (lbs)||Junctions → Pollutant Yield (lbs) (US junction)1||Output Summary → Pollutant Yield - No Controls; (A)|
|Pollutant removal (lbs)||Junctions → Pollutant Yield (lbs) (US - DS junction)1||(A) - (B)|
|Outflow Loading** (lbs)||Junctions → Pollutant Yield (lbs) (DS junction)1||Output Summary → Pollutant Yield - With Controls (B)|
|Outflow Loading (ppm; mg/L)||Junctions → Pollutant Concentration (mg/L) (DS junction)1||Output Summary → Concentration - With Controls|
|Watershed and Areal Loading Calculations|
|Contributing Watershed Area* (acres)||"Upstream Drainage Area"2 with Control Practice selected||Output Summary → Total Area Modeled (ac)|
|Watershed pollutant areal loading (pre-treatment) (lbs/acre/year)||[Watershed Loading*] / [Contributing Watershed Area*]|
|Outflow pollutant areal loading (post-treatment) (lbs/acre/year)||[Outflow Loading*] / [Contributing Watershed Area*]|
1WinSLAMM does not summarize pollutant load reduction within the "control practices" summary tab. For this reason, to calculate pollutant load reduction at control practices, "junction" elements must be placed upstream (US) and downstream (DS) of the control practice. Pollutant reduction can then be calculated as: [US junction pollutant load] - [DS junction pollutant load]. Note: using this method, pollutant reduction cannot be calculated for control practices modeled at source areas.
2While in the model space, "Upstream Drainage Area" is displayed at the bottom of the program window for the element selected.