After passage of the Minnesota Wetland Conservation Act (WCA), an interagency wetland workgroup sought to fill the need for a practical assessment tool for helping make sound wetland management decisions based on wetland functions. The Minnesota Routine Assessment Method (MnRAM) was developed and subsequently refined up until 2010. MnRAM uses a numeric model to rank each wetland function via an Excel spreadsheet. It was used most effectively for wetland inventories, and a subsequent wetland management classification system with an accompanying Access database version of the method was developed.
Updates and support for MnRAM have waned over the last 8 to 9 years as new approaches to wetland functional assessment have been developed nationally, specifically those based on the hydrogeomorphic wetland classification system (HGM). A series of regional HGM guidebooks have been developed to assess wetland functions (HGM Guidebooks). Thus far, only one regional guidebook is applicable in Minnesota (A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Prairie Potholes, 2006), and it is specific to depressional, palustrine, herbaceous, temporarily and seasonally ponded wetlands formed in glacial till in the Prairie Pothole Region (see map on page 27 of pdf document below).
BWSR no longer provides support for the MnRAM Access database version, and the file may not run on newer versions of Microsoft Access. The Excel spreadsheet continues to be the most commonly used version of MnRAM. Efforts are underway to develop new functional assessment tools for Minnesota.
While the principles and logic behind MnRAM remain sound, using MnRAM output as the sole means to compare wetlands when making wetland permitting/impact decisions is discouraged by BWSR. MnRAM lacks the precision to make very specific comparisons in these situations. However, MnRAM outputs can be useful when used in conjunction with other characteristics and professional judgment. The following documents include guidance on using MnRAM as well as the Excel spreadsheet and Access database versions.