Minnesota Stream Quantification Tool and Debit Calculator
Use and Applicability
The Minnesota Stream Quantification Tool and Debit Calculator (MNSQT) are spreadsheet based tools designed to inform permitting and compensatory mitigation decisions related to streams. The MNSQT can also be applied to restoration projects outside of a regulatory context to assess and compare their functional lift. The main goal of the MNSQT is to produce objective, verifiable, and repeatable results by consolidating well-defined procedures for objective and quantitative measures of defined stream variables.
For the Wetland Conservation Act (WCA) specifically, Minnesota Statutes 103G.2242, subdivision 12 was amended in 2015 to allow wetland replacement credits for the restoration and protection of streams in the northeastern portion of the state. The criteria for generating wetland replacement credits for stream restoration and protection is being developed through BWSR's rulemaking authority. An essential part of this effort is the creation of the technical tools necessary to equitably and consistently allocate replacement credit for stream restoration based on functional lift. The MNSQT provides this important tool for which the rules, policies and guidance on generating credit for stream restoration projects can follow.
The MNSQT and Debit Calculator are being made available on BWSR's website to allow for review and use by stream restoration practitioners working in Minnesota. Although the mechanism to generate wetland replacement credits for stream restoration under the WCA will not be in place until rulemaking is completed, BWSR intends to propose rules, policies and guidance based in part on the use of this tool.
The MNSQT is being used by the St. Paul District Army Corps of Engineers under their new stream mitigation policy for Section 404 of the Clean Water Act (Corps Public Notice). In addition, it may help inform permitting decisions related to projects affecting streams under Section 401 of the Clean Water Act as implemented by the MN Pollution Control Agency and the DNR Protected Waters Permit Program. Potential users should contact those regulatory agencies directly with questions about the use of the tool for the regulatory programs they administer.
Background on Tool Development
The U.S. Environmental Protection Agency (USEPA) provided funding for a consultant, Stream Mechanics, to develop the MNSQT and Debit Calculator. The USEPA, St. Paul District Army Corps of Engineers, MN Department of Natural Resources, MN Pollution Control Agency and the MN Board of Water and Soil Resources participated cooperatively in the MNSQT development. The MNSQT is an application of the Stream Functions Pyramid Framework (Stream Mechanics website) and uses function-based parameters and metrics to assess five functional categories: Hydrology, Hydraulics, Geomorphology, Physicochemical, and Biology. Other stream quantification tools and user manuals have been developed for use in other states and regions, including North Carolina, Tennessee, Georgia, and Colorado. Further information on development of this tool is available in the MNSQT User Manual.
The MNSQT User Manual provides data collection methods related to each metric used to evaluate functional lift. For some metrics, methods include both rapid and more detailed forms of data collection, allowing the tool to be used for rapid or more comprehensive site assessment. The user manual describes the MNSQT and Debit Calculator workbooks and how to collect and analyze data entered into these workbooks. Companion documents include Appendix A (specific field data collection methods for certain metrics), Appendix B (Excel Workbook Field Forms), other documentation forms (riparian vegetation, large woody debris, macroinvertebrate and fish), the MNSQT Excel Workbook (to enter field values and run calculations) and a scientific support document for the Debit Calculator portion of the tool. A scientific support document for the overall tool is being finalized and will be provided upon completion.
Other documentation forms: