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+ | {{alert|This page is for guidance related to the TMDL Annual Reporting Form for the 2013 General Permit. Reporting for the 2020 General Permit will not be due until June 30, '''2024'''. |alert-info}} | ||
This User Guide is intended to assist Municipal Separate Storm Sewer System (MS4) Permittees in the completion of the Commissioner-approved [[Upload page with TMDL forms|TMDL Annual Reporting Form]] (TMDL Form). | This User Guide is intended to assist Municipal Separate Storm Sewer System (MS4) Permittees in the completion of the Commissioner-approved [[Upload page with TMDL forms|TMDL Annual Reporting Form]] (TMDL Form). | ||
+ | |||
+ | A tutorial video on how to fill out your form is available [https://www.youtube.com/watch?v=9kIgqVBBqd8&feature=youtu.be here]. | ||
Quickguides have been created for two of the worksheets in the form. | Quickguides have been created for two of the worksheets in the form. | ||
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*Stream TMDLs: For ease of reporting, the Permittee is allowed to report on groupings of WLAs within the same report. Stream TMDLs will therefore be labeled by TMDL Project Name + Pollutant. For example, if the Permittee has TSS WLAs on four stream reaches in a single project, these will be grouped into one TMDL to report on. If the Permittee has been assigned WLAs for bacteria on the same four stream reaches in the same project, the Permittee would have two TMDLs to report on. Note that a Permittee may request to have the form customized to allow for individual reach reporting, however, the grouping convention will be the default.|alert-info}} | *Stream TMDLs: For ease of reporting, the Permittee is allowed to report on groupings of WLAs within the same report. Stream TMDLs will therefore be labeled by TMDL Project Name + Pollutant. For example, if the Permittee has TSS WLAs on four stream reaches in a single project, these will be grouped into one TMDL to report on. If the Permittee has been assigned WLAs for bacteria on the same four stream reaches in the same project, the Permittee would have two TMDLs to report on. Note that a Permittee may request to have the form customized to allow for individual reach reporting, however, the grouping convention will be the default.|alert-info}} | ||
− | The MPCA | + | The MPCA does post the previous year's [https://stormwater.pca.state.mn.us/index.php?title=Annual_TMDL_forms_submitted_by_MS4_permittees TMDL Annual Report Form submittal] at the beginning of each calendar year. However, the Permittee is responsible for maintaining their TMDL Form. The same form will be updated by the Permittee throughout the permit cycle. The Permittee will submit the form each annual reporting year, starting with the 2014 Annual Report. The MPCA will maintain copies of all submitted files. |
The TMDL Form is an Excel workbook that includes nine (9) color coded tabs (worksheets): | The TMDL Form is an Excel workbook that includes nine (9) color coded tabs (worksheets): | ||
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'''List of TMDLs''' (Yellow Tab) is a reference worksheet, which contains a list of all the TMDLs in Minnesota with MS4 stormwater WLAs approved by the USEPA before the effective date of the MS4 General Permit, August 1, 2013. The MPCA is responsible for maintaining this information. The User cannot edit this information. This tab is hidden. | '''List of TMDLs''' (Yellow Tab) is a reference worksheet, which contains a list of all the TMDLs in Minnesota with MS4 stormwater WLAs approved by the USEPA before the effective date of the MS4 General Permit, August 1, 2013. The MPCA is responsible for maintaining this information. The User cannot edit this information. This tab is hidden. | ||
− | '''MPCA estimator''' (Blue Tab) is an optional User input tab that allows the User to estimate the cumulative reduction (mass or percent removal) of a pollutant of concern achieved by implementation of BMPs. The reductions calculated here can be used when entering information into the quantitative reductions portion of the Cumulative reductions tab ([[Guidance and examples for using the MPCA Estimator]]). This tab is hidden. | + | '''MPCA estimator''' (Blue Tab) is an optional User input tab that allows the User to estimate the cumulative reduction (mass or percent removal) of a pollutant of concern achieved by implementation of BMPs. The reductions calculated here can be used when entering information into the quantitative reductions portion of the Cumulative reductions tab ([[Guidance and examples for using the MPCA Estimator]]). This tab is hidden. |
+ | <br /> | ||
'''Input values for the MPCA estimator''' (Yellow Tab) contains the information used in the MPCA estimator worksheet. Information here is based on literature reviews and therefore general in nature and may not accurately reflect the User site conditions. Therefore, the User is encouraged, as much as is possible, to use their own site data to fill in the cells in the MPCA estimator worksheet. This tab is hidden. | '''Input values for the MPCA estimator''' (Yellow Tab) contains the information used in the MPCA estimator worksheet. Information here is based on literature reviews and therefore general in nature and may not accurately reflect the User site conditions. Therefore, the User is encouraged, as much as is possible, to use their own site data to fill in the cells in the MPCA estimator worksheet. This tab is hidden. | ||
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*Source of Information: User | *Source of Information: User | ||
− | {{alert|If this is the first year using this form, BMPs should be entered for the previous calendar year and all prior years back to the baseline year of the TMDL. These records should all be reported as 2014 entries. Reports in subsequent years will accumulate any BMPs added in the reporting year (ex. The 2016 Annual report will show BMPs back to the baseline year, as well as those added in 2015). | + | {{alert|If this is the first year using this form, BMPs should be entered for the previous calendar year and all prior years back to the baseline year of the TMDL. These records should all be reported as 2014 entries. Reports in subsequent years will accumulate any BMPs added in the reporting year (ex. The 2016 Annual report will show BMPs back to the baseline year, as well as those added in 2015). Additional guidance on determining your baseline year is provided [[Baseline year|here]].|alert-info}} |
=====Column E – BMP/Activity===== | =====Column E – BMP/Activity===== | ||
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<div style="background-color: none; border-style: solid;"> | <div style="background-color: none; border-style: solid;"> | ||
*Use Category 1 if '''all''' of the following apply. | *Use Category 1 if '''all''' of the following apply. | ||
− | **Pollutant loadings from the BMP/activity can be estimated using an [[ | + | **Pollutant loadings from the BMP/activity can be estimated using an [[Stormwater model and calculator comparisons|appropriate method]] |
**The pollutant is phosphorus, TSS, fecal coliform, or E. coli | **The pollutant is phosphorus, TSS, fecal coliform, or E. coli | ||
**The BMP/activity was constructed '''within your jurisdiction''' (upstream of your MS4's outfall) | **The BMP/activity was constructed '''within your jurisdiction''' (upstream of your MS4's outfall) | ||
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− | The purpose of this category is to provide a quantitative estimate of the cumulative reductions in loading achieved for each TMDL WLA applicable to the permittee. This category should be used when reductions in pollutant loading are achieved by BMPs constructed '''within a permittee's jurisdiction''' and can be quantified using an [[ | + | The purpose of this category is to provide a quantitative estimate of the cumulative reductions in loading achieved for each TMDL WLA applicable to the permittee. This category should be used when reductions in pollutant loading are achieved by BMPs constructed '''within a permittee's jurisdiction''' and can be quantified using an [[Stormwater model and calculator comparisons|appropriate method]] for one of the following pollutants. |
*Total phosphorus | *Total phosphorus | ||
*Total suspended solids | *Total suspended solids | ||
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*Use Category 2 if '''any''' of the following applies. | *Use Category 2 if '''any''' of the following applies. | ||
**Pollutant is Biochemical Oxygen Demand (BOD), Nitrogenous Biochemical Oxygen Demand (NBOD), chloride, or thermal loading | **Pollutant is Biochemical Oxygen Demand (BOD), Nitrogenous Biochemical Oxygen Demand (NBOD), chloride, or thermal loading | ||
− | **Pollutant reduction information from the BMP/activity is not readily available using an [[ | + | **Pollutant reduction information from the BMP/activity is not readily available using an [[Stormwater model and calculator comparisons|appropriate method]] |
**You contribute(d) to the implementation of the BMP/activity but the reduction in pollutant loading occurs '''outside your jurisdictional area''' (e.g. you contributed funding to a BMP in another MS4's jurisdiction) | **You contribute(d) to the implementation of the BMP/activity but the reduction in pollutant loading occurs '''outside your jurisdictional area''' (e.g. you contributed funding to a BMP in another MS4's jurisdiction) | ||
</div> | </div> | ||
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{{alert|The information in this worksheet is summary in nature. MS4 permittees are advised to maintain a record of the data used to complete this form, including information such as BMP name, total annual pollutant load reduction, technique used to compute pollutant load reduction, date the BMP went into operation, and other information that may assist the MS4 Permittee. Some of this information may be included in the BMPs-Activities completed worksheet.|alert-info}} | {{alert|The information in this worksheet is summary in nature. MS4 permittees are advised to maintain a record of the data used to complete this form, including information such as BMP name, total annual pollutant load reduction, technique used to compute pollutant load reduction, date the BMP went into operation, and other information that may assist the MS4 Permittee. Some of this information may be included in the BMPs-Activities completed worksheet.|alert-info}} | ||
− | Three categories of reporting are described in detail above. The choice of category for reporting is dependent on whether the BMPs/activities are required to be quantified for the pollutant of concern. Recommendations for the choice of Category are provided above. For Category 1 and Category 2, it is assumed the BMP/activity was in operation during the previous year, or if this is your first reporting year, between the baseline year or BMP condition of the TMDL and the past year | + | Three categories of reporting are described in detail above. The choice of category for reporting is dependent on whether the BMPs/activities are required to be quantified for the pollutant of concern. Recommendations for the choice of Category are provided above. For Category 1 and Category 2, it is assumed the BMP/activity was in operation during the previous year, or if this is your first reporting year, between the [[Baseline year|baseline year]] or BMP condition of the TMDL and the past year. |
====Detailed guidance for the Cumulative reductions tab - Category 1==== | ====Detailed guidance for the Cumulative reductions tab - Category 1==== | ||
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====Estimation of pollutant load reduction for the Cumulative reductions tab==== | ====Estimation of pollutant load reduction for the Cumulative reductions tab==== | ||
− | The TMDL Form requires Permittees to estimate pollutant reductions for BMPs/activities that have established pollutant removal values for phosphorus, TSS, fecal coliform bacteria, or E. coli bacteria. “Established pollutant removal value” means the Stormwater Manual provides values for pollutant removal or MPCA has included a pollutant removal value in the | + | The TMDL Form requires Permittees to estimate pollutant reductions for BMPs/activities that have established pollutant removal values for phosphorus, TSS, fecal coliform bacteria, or E. coli bacteria. “Established pollutant removal value” means the Stormwater Manual provides values for pollutant removal or MPCA has included a pollutant removal value in the [[Guidance and examples for using the MPCA Estimator|MPCA Estimator]]. |
In addition to the values provided in the TMDL Form, MS4 Permittees have multiple options for determining the pollutant load reduction of a specific BMP. The Permittee may opt to use any of these techniques. Permittees are encouraged to record the methodology utilized for computing pollutant load reductions in order to manage the data and changes that can occur each reporting year. | In addition to the values provided in the TMDL Form, MS4 Permittees have multiple options for determining the pollutant load reduction of a specific BMP. The Permittee may opt to use any of these techniques. Permittees are encouraged to record the methodology utilized for computing pollutant load reductions in order to manage the data and changes that can occur each reporting year. | ||
=====Models and calculators===== | =====Models and calculators===== | ||
− | The Minnesota Stormwater Manual contains an up-to-date list of [ | + | The Minnesota Stormwater Manual contains an up-to-date list of [http://stormwater.pca.state.mn.us/index.php/Stormwater_model_and_calculator_comparisons models and calculators] that can be used to compute the pollutant removal of a specific BMP. The models range from complex software that calculate hydrology/hydraulics/water quality such as USEPA SWMM, to User friendly calculators such as the MIDS calculator. Permittees are advised to consider the following. |
*Stand-alone water quality models, such as P8, work well for situations that do not require a hydraulic analysis. | *Stand-alone water quality models, such as P8, work well for situations that do not require a hydraulic analysis. | ||
*Complex models such as SWMM work well for watersheds with multiple BMPs, but may require a MS4 Permittee to hire a modeling expert or consultant. | *Complex models such as SWMM work well for watersheds with multiple BMPs, but may require a MS4 Permittee to hire a modeling expert or consultant. | ||
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=====MPCA Estimator===== | =====MPCA Estimator===== | ||
− | + | An [[Guidance and examples for using the MPCA Estimator|additional worksheet]] has been created for the purpose of estimating pollutant load reductions using published reductions in Event Mean Concentration (EMC). Use of this worksheet is optional. This estimator is intended solely for computing load reductions for this form and is not intended to report on the exact performance of an individual BMP. See [[Guidance and examples for using the MPCA Estimator]] for more information. | |
===Category 3 BMPs - Activities Tab=== | ===Category 3 BMPs - Activities Tab=== | ||
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This tab contains a worksheet that should include all BMPs and activities listed in the compliance schedule of the permit application that have not been completed. Over time these BMPs or activities may be completed and then moved into Category 1 or Category 2. Activities that constitute progress but do not achieve a reduction, such as planning, feasibility studies, acquisition of funding, etc., are the only records that will remain in Category 3. | This tab contains a worksheet that should include all BMPs and activities listed in the compliance schedule of the permit application that have not been completed. Over time these BMPs or activities may be completed and then moved into Category 1 or Category 2. Activities that constitute progress but do not achieve a reduction, such as planning, feasibility studies, acquisition of funding, etc., are the only records that will remain in Category 3. | ||
+ | |||
+ | You may view and download a copy of your compliance schedule by entering "file: [your MS4's name]" into the search box located in the upper right hand corner of this page. For example "file: City of Rochester". Click on the search result named "[your MS4's name SWPPP Document.pdf" to view and download. | ||
====Columns A and B – MS4 Information==== | ====Columns A and B – MS4 Information==== | ||
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====Column E – Status==== | ====Column E – Status==== | ||
− | *Description: Status of planned BMP | + | *Description: Status of planned BMP. If the options in the dropdown menu don't work, please enter the status in the "Notes" section. |
*Input: Planned, funded, under construction, or other user-specified status | *Input: Planned, funded, under construction, or other user-specified status | ||
*Source of Information: Dropdown box | *Source of Information: Dropdown box | ||
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====Input values for MPCA estimator==== | ====Input values for MPCA estimator==== | ||
[[file:screen shot estimator inputs.png|300px|thumb|alt=screen shot of estimator inputs tab|<font size=3>Screen shot of the ''Estimator inputs'' tab.</font size>]] | [[file:screen shot estimator inputs.png|300px|thumb|alt=screen shot of estimator inputs tab|<font size=3>Screen shot of the ''Estimator inputs'' tab.</font size>]] | ||
+ | |||
+ | Download MPCA Estimator here: [[file:MPCA_Estimator.xlsx]] | ||
This tab contains three types of information. The first is the fraction of pollutant removed from the stormwater runoff due to the presence of a BMP. The values apply to stormwater runoff that does not infiltrate into underlying soil. For water that infiltrates into the underlying soil, the pollutant removal fraction is 1.0. Any remaining runoff will bypass the system and cannot be considered for pollutant removal. Therefore the removal fraction for these BMPs is 0 because it only applies to the water that is not infiltrating into underlying soil. The pollutant removal fraction for infiltrated water equals the fraction of water that infiltrates. These values are included in cells C37, C58, C79, and C100 in the MPCA estimator tab. The default value for fraction that infiltrates is 0.90, which corresponds approximately with a BMP designed to capture a 1 inch rain event. All removal fractions are based on the assumption that BMPs were properly designed, constructed and maintained. See specifications and guidance for design, construction and maintenance of individual BMPs in the Minnesota Stormwater Manual. Removal fractions are consistent with values presented in the Stormwater Manual and the [[MIDS calculator|Minimal Impact Design Standards calculator]]. | This tab contains three types of information. The first is the fraction of pollutant removed from the stormwater runoff due to the presence of a BMP. The values apply to stormwater runoff that does not infiltrate into underlying soil. For water that infiltrates into the underlying soil, the pollutant removal fraction is 1.0. Any remaining runoff will bypass the system and cannot be considered for pollutant removal. Therefore the removal fraction for these BMPs is 0 because it only applies to the water that is not infiltrating into underlying soil. The pollutant removal fraction for infiltrated water equals the fraction of water that infiltrates. These values are included in cells C37, C58, C79, and C100 in the MPCA estimator tab. The default value for fraction that infiltrates is 0.90, which corresponds approximately with a BMP designed to capture a 1 inch rain event. All removal fractions are based on the assumption that BMPs were properly designed, constructed and maintained. See specifications and guidance for design, construction and maintenance of individual BMPs in the Minnesota Stormwater Manual. Removal fractions are consistent with values presented in the Stormwater Manual and the [[MIDS calculator|Minimal Impact Design Standards calculator]]. | ||
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*infiltrator: a stormwater treatment practice designed to allow captured runoff to infiltrate into soil underlying the practice. Includes bioretention with no underdrain (rain garden), infiltration basin, infiltration trench, permeable pavement with no underdrain, tree trench/tree box/planter, underground infiltration, or other similar BMPs. | *infiltrator: a stormwater treatment practice designed to allow captured runoff to infiltrate into soil underlying the practice. Includes bioretention with no underdrain (rain garden), infiltration basin, infiltration trench, permeable pavement with no underdrain, tree trench/tree box/planter, underground infiltration, or other similar BMPs. | ||
*swale or strip: a linear stormwater treatment practice designed to treat pollutants through settling and filtering. If the device is designed to infiltrate runoff, it is considered an infiltrator. Includes dry swale, filter strip/buffer, grass channel/waterway, level spreader, wet swale, or other similar BMPs. | *swale or strip: a linear stormwater treatment practice designed to treat pollutants through settling and filtering. If the device is designed to infiltrate runoff, it is considered an infiltrator. Includes dry swale, filter strip/buffer, grass channel/waterway, level spreader, wet swale, or other similar BMPs. | ||
+ | |||
+ | ==Related Pages== | ||
+ | [[Summary of TMDL requirements in stormwater permits]]<br /> | ||
+ | [[Forms, guidance, and resources for completing the TMDL annual report form]]<br /> | ||
+ | [[Examples for completing the TMDL reporting form]]<br /> | ||
+ | [[Upload page with TMDL forms]]<br /> | ||
+ | [[Guidance and examples for using the MPCA Estimator]]<br /> | ||
+ | [[Quick Guide: BMP-Activities completed tab]]<br /> | ||
+ | [[Quick Guide: Cumulative reductions tab]]<br /> |
This User Guide is intended to assist Municipal Separate Storm Sewer System (MS4) Permittees in the completion of the Commissioner-approved TMDL Annual Reporting Form (TMDL Form).
A tutorial video on how to fill out your form is available here.
Quickguides have been created for two of the worksheets in the form.
Examples showing how to complete the form are contained in another guidance document.
If you (an MS4 Permittee) are assigned one or more Wasteload Allocation (WLA) in a Total Maximum Daily Load (TMDL) that was approved by the United States Environmental Protection Agency (USEPA) prior to August 1, 2013, and were not meeting the WLA(s) when you applied for permit coverage, you must complete this form to demonstrate progress toward meeting the WLA(s).
Submission of this form fulfills the permit requirement (Part III.E) to demonstrate continuing progress toward achieving WLAs . This is achieved by including information on one or more of the following in the TMDL Form.
Specific language that requires MS4 Permittees to submit progress towards meeting a WLA is contained in Part III.E of MPCA Permit No: MNR040000, effective August 1, 2013. Requirements include Stormwater Pollution Prevention Program (SWPPP) development and Annual Reporting.
All MS4 Permittees that manage a stormwater discharge to an impaired water with a TMDL approved by the USEPA prior to August 1, 2013, have incorporated information for each applicable WLA in their SWPPP documents, as required in Part II.D.6 of MPCA Permit No: MNR040000, effective August 1, 2013.
Permittees with applicable WLAs shall submit the TMDL Form along with the MS4 Annual Report to the MPCA by June 30th of each calendar year, beginning in 2015. Additional information regarding the MS4 General Permit schedule and the SWPPP Submittal Schedule can be found in Appendix A of the MS4 General Permit and on the MPCA’s MS4 Annual Report web page.
Each Permittee will have a custom TMDL Form created by the MPCA that lists WLAs affecting the Permittee. All WLAs applicable to a Permittee may not be included in the form. There are two scenarios in which this may occur:
You are only responsible for reporting on WLAs included in your customized form.
The MPCA does post the previous year's TMDL Annual Report Form submittal at the beginning of each calendar year. However, the Permittee is responsible for maintaining their TMDL Form. The same form will be updated by the Permittee throughout the permit cycle. The Permittee will submit the form each annual reporting year, starting with the 2014 Annual Report. The MPCA will maintain copies of all submitted files.
The TMDL Form is an Excel workbook that includes nine (9) color coded tabs (worksheets):
Spreadsheet user information (Blue Tab) is an optional worksheet that contains general information for the User. The MPCA recommends that Permittees keep this sheet updated as a means of tracking entries into the TMDL Form.
BMPs-Activities completed (Green Tab) is a required worksheet. The User enters data related to specific BMPs or activities that were completed during the reporting period (January 1 - December 31 of the year prior to form due date or since baseline for the first year of reporting) and that are applied to meeting an applicable WLA. BMPs/activities are associated with each applicable TMDL WLA.
Cumulative reductions (Green Tab) is a required worksheet. The User enters data regarding the estimated pollutant load reduction(s) resulting from implementation of BMPs/activities and information on BMPs/Activities being applied to applicable WLAs.
Category 3 BMPs-Activities (Green Tab) is a required worksheet. The User enters data regarding activities that were included in their SWPPP submittal but that have not yet been implemented.
Adaptive management strategy (Green tab) is a required worksheet. The User provides a narrative describing any adaptive management strategies used for making progress toward achieving each applicable WLA.
List of TMDLs (Yellow Tab) is a reference worksheet, which contains a list of all the TMDLs in Minnesota with MS4 stormwater WLAs approved by the USEPA before the effective date of the MS4 General Permit, August 1, 2013. The MPCA is responsible for maintaining this information. The User cannot edit this information. This tab is hidden.
MPCA estimator (Blue Tab) is an optional User input tab that allows the User to estimate the cumulative reduction (mass or percent removal) of a pollutant of concern achieved by implementation of BMPs. The reductions calculated here can be used when entering information into the quantitative reductions portion of the Cumulative reductions tab (Guidance and examples for using the MPCA Estimator). This tab is hidden.
Input values for the MPCA estimator (Yellow Tab) contains the information used in the MPCA estimator worksheet. Information here is based on literature reviews and therefore general in nature and may not accurately reflect the User site conditions. Therefore, the User is encouraged, as much as is possible, to use their own site data to fill in the cells in the MPCA estimator worksheet. This tab is hidden.
Dropdown lists (Yellow Tab) contains a list of the inputs for the dropdown lists found in the BMPs-Activities completed and Cumulative reductions worksheets. The MPCA is responsible for maintaining this tab. The User cannot edit this information. This tab is hidden.
The tab titled Spreadsheet user information contains an optional worksheet that can be used to track the most current version of the form. There are two boxes contained in this worksheet.
The worksheet tab called BMP-Activities completed is used to record compliance with the requirement to demonstrate continuing progress towards meeting applicable WLAs. The Permittee is only required to report BMPs being applied toward applicable WLAs.
The content of this worksheet is shown in the two figures below. Grey cells are filled out by the MPCA and cannot be edited by the Permittee. White cells are MS4 User input cells. Brown cells are optional MS4 User input cells but are highly encouraged. Note that some of these white cells are optional or may be auto-filled depending on inputs in other white cells. Information required in this worksheet includes:
If the BMP chosen in Column E of the tab is a constructed basin, filter, infiltrator, or swale or strip, the User is required to enter, in columns H through K,
If another BMP is entered in Column E, cells in Columns H through K will auto fill with “NA”. Optional information includes the year that the BMP was implemented and any additional notes. Detailed guidance on each of these columns can be found below.
A BMP may only be reported in one of the three categories. While BMPs may move from one category to another between years, they may not be reported in more than one category in a single report.
The purpose of this category is to provide a quantitative estimate of the cumulative reductions in loading achieved for each TMDL WLA applicable to the permittee. This category should be used when reductions in pollutant loading are achieved by BMPs constructed within a permittee's jurisdiction and can be quantified using an appropriate method for one of the following pollutants.
The following options exist for reporting load or load reduction.
The following BMP/activities require estimated reductions in loading under Category 1:
These BMPs are included or can be simulated in most water quality models and calculators used for estimating stormwater loading. The Minnesota Stormwater Manual also provides typical reduction efficiencies for these BMPs. Note that you may have information that allows for quantifying pollutant reductions for BMPs other than those listed above, or you may have different pollutant removal values based on local data. For example, many water quality models and calculators will calculate pollutant reductions associated with street sweeping. MPCA encourages permittees to keep a record of methodology used to calculate reductions.
The following BMPs may be quantifiable. However, the Stormwater Manual either provides limited or no pollutant removal efficiencies or guidance for these BMPs, so it is suggested that they be reported under Category 2.
The purpose of this category is to acknowledge BMPs/activities that likely reduce pollutant loads but lack information for estimating load reductions or reduce pollutant loads outside the permittee's MS4. Entries in this category are numbers of BMPs; not a reduction value. This category should be used to track those BMPs or activities that operate in one or more of the following conditions.
As with Category 1, the value entered represents a cumulative value, in this case the total number of BMPs/activities that are applied to a TMDL Project. All BMPs and activities included in this number must be included in the BMPs-Activities completed tab.
The purpose of this category is to capture progress made that did not directly result in a pollutant reduction. In this section, the Permittee must report on planned BMPs that have not yet been implemented but were submitted as a part of the compliance schedule in the MS4 Permit TMDL Attachment spreadsheet at the time of application. This could include both structural and non-structural BMPs/activities. Activities that constitute progress but do not achieve a reduction, such as planning, feasibility studies, acquisition of funding, etc., will be left in Category 3. When activities that can reduce pollutants are implemented, those reductions should be reported in Category 1 or 2, and removed from this worksheet.
The worksheet called Cumulative reductions is used to track the annual cumulative progress towards reduction of pollutants discharged to an impaired water with a USEPA approved TMDL. Cumulative progress may be reported in terms of measured or calculated pollutant reductions or number of BMPs implemented. Completion of this, the Category 3 BMPs - Activities, and Adaptive management worksheets fulfill compliance with Section III.E.3 of the MS4 General Permit (Permit Number MNR040000).
The contents of this worksheet are shown in the figure to the right. As with the BMPs-Activities completed worksheet, cells that are grey are column/row headings and cells that the MPCA will fill out for each MS4. Cells that are white are User input cells.
Three categories of reporting are described in detail above. The choice of category for reporting is dependent on whether the BMPs/activities are required to be quantified for the pollutant of concern. Recommendations for the choice of Category are provided above. For Category 1 and Category 2, it is assumed the BMP/activity was in operation during the previous year, or if this is your first reporting year, between the baseline year or BMP condition of the TMDL and the past year.
These are numbers of BMPs or activities that have been implemented but are not quantified in terms of pollutant reduction.
The TMDL Form requires Permittees to estimate pollutant reductions for BMPs/activities that have established pollutant removal values for phosphorus, TSS, fecal coliform bacteria, or E. coli bacteria. “Established pollutant removal value” means the Stormwater Manual provides values for pollutant removal or MPCA has included a pollutant removal value in the MPCA Estimator.
In addition to the values provided in the TMDL Form, MS4 Permittees have multiple options for determining the pollutant load reduction of a specific BMP. The Permittee may opt to use any of these techniques. Permittees are encouraged to record the methodology utilized for computing pollutant load reductions in order to manage the data and changes that can occur each reporting year.
The Minnesota Stormwater Manual contains an up-to-date list of models and calculators that can be used to compute the pollutant removal of a specific BMP. The models range from complex software that calculate hydrology/hydraulics/water quality such as USEPA SWMM, to User friendly calculators such as the MIDS calculator. Permittees are advised to consider the following.
The Minnesota Stormwater Manual sections on Stormwater Management Credits offer four options to calcuate the pollutant removal for a number of BMPs. The term Credit implies pollutant loading and volume reductions. BMPs that have Credit sections include:
Four calculation methods are described in detail in each of these BMP Credit sections.
An additional worksheet has been created for the purpose of estimating pollutant load reductions using published reductions in Event Mean Concentration (EMC). Use of this worksheet is optional. This estimator is intended solely for computing load reductions for this form and is not intended to report on the exact performance of an individual BMP. See Guidance and examples for using the MPCA Estimator for more information.
This tab contains a worksheet that should include all BMPs and activities listed in the compliance schedule of the permit application that have not been completed. Over time these BMPs or activities may be completed and then moved into Category 1 or Category 2. Activities that constitute progress but do not achieve a reduction, such as planning, feasibility studies, acquisition of funding, etc., are the only records that will remain in Category 3.
You may view and download a copy of your compliance schedule by entering "file: [your MS4's name]" into the search box located in the upper right hand corner of this page. For example "file: City of Rochester". Click on the search result named "[your MS4's name SWPPP Document.pdf" to view and download.
The NPDES MS4 permit requires permittees to provide “(a)n up-dated narrative describing any adaptive management strategies used (including projected dates) for making progress toward achieving each applicable WLA”. This tab contains a text box for users to submit this narrative.
Adaptive management (AM) is a formal process for continually improving management policies and practices by learning from their outcomes. This portion of the annual report should describe the permittee's plan for continuing to demonstrate progress toward achieving applicable WLAs through development and implementation of structural and non-structural BMPs (e.g., project funding details, details of a feasibility study, efforts to establish partnerships, updates on construction of a structural BMP, etc.). This is also the portion of the annual report that would describe any changes to the compliance schedule the permittee wishes to pursue based on past observations and recognized program enhancement opportunities.
Example: The city has used the first year of the permit term to evaluate its status in regard to WLAs for two lake phosphorus TMDLs. An assessment of implemented BMPs found that additional reductions will need to be made in order to achieve the WLAs. The city is currently determining the most cost effective strategies for meeting these goals. There is a stormwater utility fee in place that will be used to fund these Capital Improvement Projects going forward. A creative approach will need to be applied being that the city is completely built out. As redevelopment occurs, additional stormwater management practices will be evaluated and installed. Construction schedules are variable and future annual reports submitted to the MPCA by the city will provide updates made to the city’s compliance schedule. New and improved technology will also be monitored throughout the current permit term and implemented when feasible going forward.
The three yellow tabs within the TMDL form are reference tabs. These are hidden when the Excel file is initially opened but can be made visible. The Dropdown lists tab was created solely to build the form and does not contain information helpful to the User. The other tabs are the List of TMDLs and the Input values for MPCA estimator. These are described in more detail below.
Download MPCA Estimator here: File:MPCA Estimator.xlsx
This tab contains three types of information. The first is the fraction of pollutant removed from the stormwater runoff due to the presence of a BMP. The values apply to stormwater runoff that does not infiltrate into underlying soil. For water that infiltrates into the underlying soil, the pollutant removal fraction is 1.0. Any remaining runoff will bypass the system and cannot be considered for pollutant removal. Therefore the removal fraction for these BMPs is 0 because it only applies to the water that is not infiltrating into underlying soil. The pollutant removal fraction for infiltrated water equals the fraction of water that infiltrates. These values are included in cells C37, C58, C79, and C100 in the MPCA estimator tab. The default value for fraction that infiltrates is 0.90, which corresponds approximately with a BMP designed to capture a 1 inch rain event. All removal fractions are based on the assumption that BMPs were properly designed, constructed and maintained. See specifications and guidance for design, construction and maintenance of individual BMPs in the Minnesota Stormwater Manual. Removal fractions are consistent with values presented in the Stormwater Manual and the Minimal Impact Design Standards calculator.
The second type of information is the event mean concentration (EMC) of total phosphorus, TSS, E. coli, and fecal coliform in stormwater runoff in the various land use areas. The 2011 National Stormwater Quality Database is the primary source of this information. Cells in the worksheet are populated with mean or median values from the Upper Midwest (Zone 1), but the User may enter a different value if they have reliable data.
The third type of information is the runoff coefficient (Rv) for the various land use types. The input values are based on literature. The default is set at the median of values from the literature. The User may enter a value if available data supports the value. For a discussion of runoff coefficients, see [4].
If a user wishes to provide any of the above information specific to their site for input into the Estimator, they may change the numbers here in the input tab and they will be transferred to the Estimator. These values are locked in the Estimator tab to avoid accidental edits.
Download here: File:Cross-Reference list.xlsx
The cross-reference list is included in a separate Excel spreadsheet rather than the TMDL spreadsheet because the MPCA realizes the BMP list is likely to grow over time. The cross-reference file will be updated as needed.
Summary of TMDL requirements in stormwater permits
Forms, guidance, and resources for completing the TMDL annual report form
Examples for completing the TMDL reporting form
Upload page with TMDL forms
Guidance and examples for using the MPCA Estimator
Quick Guide: BMP-Activities completed tab
Quick Guide: Cumulative reductions tab