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+ | The MPCA Simple Estimator is a spreadsheet tool that calculates pollutant loading and load reductions associated with stormwater best management practices (BMPs). The spreadsheet utilizes the Simple Method. | ||
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+ | This page provides answers to some questions about the Estimator. Like any calculation tool or model, there is a certain amount of user expertise and best professional judgement involved in calculating stormwater loads and load reductions. Consequently, some of the information on this page reflects recommendations for how to use the Estimator rather than specific answers and approaches. | ||
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==General questions== | ==General questions== | ||
+ | *How is acreage determined for Section 1 of the Estimator? | ||
+ | **The Estimator requires the user to assign acreages to different land uses. Each land use has associated event mean concentrations and runoff coefficients, which affect the total pollutant load. It is therefore important to accurately portray the study area and assign correct acreages to each land use. We recommend the user initially develop a site map and delineate land uses on that map. Then determine acreages associated with each land use and enter into Section 1 of the spreadsheet. | ||
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+ | ==Loads== | ||
+ | *Are the loads calculated in Sections 1 (unadjusted loads) and 2 (adjusted loads) for all runoff or just treated runoff? | ||
+ | **The loads in these sections are for all stormwater runoff, which is a function of rainfall and the runoff coefficient. In Sections 3 and 4, the user specifies how much of the total annual runoff is treated. | ||
+ | *How does the baseline year in a TMDL factor into the calculations? | ||
The MPCA Simple Estimator is a spreadsheet tool that calculates pollutant loading and load reductions associated with stormwater best management practices (BMPs). The spreadsheet utilizes the Simple Method.
This page provides answers to some questions about the Estimator. Like any calculation tool or model, there is a certain amount of user expertise and best professional judgement involved in calculating stormwater loads and load reductions. Consequently, some of the information on this page reflects recommendations for how to use the Estimator rather than specific answers and approaches.