Updating the National Wetlands Inventory for Minnesota

Overall Project Outcome and Results
Over the past 100 years, about half of Minnesota's original 22 million acres of wetlands have been drained or filled. Some regions of the State have lost more than 90 percent of their original wetlands. Urban development, agricultural drainage, mining, road construction, and utility projects result in additional losses each year. The National Wetland Inventory (NWI) is the only comprehensive inventory of wetlands for Minnesota, but it is inaccurate in many places because it is 25-30 years out-of-date. Updating the NWI is a key component of the State's strategy to monitor and assess wetlands in support of efforts to assure healthy wetlands and clean water for Minnesota.

This project is the first phase of a multi-phase effort to update the NWI for all of Minnesota. Under this project, the project team:

1. developed wetland mapping standards and quality control objectives to assure that the final product can meet the broad array of data needs for various stakeholders,
2. developed a request for proposal that incorporates these standards and objectives,
3. acquired high-resolution, spring, leaf-off, digital aerial photography for northeastern and east-central Minnesota (22,500 square miles),
4. developed updated wetland mapping procedures for northeastern and east-central Minnesota that incorporate modern high-resolution digital imagery, radar imagery, and LiDAR elevation data,
5. provided training to DNR and Ducks Unlimited staff (total of six people) on the application of the updated wetland mapping procedures, and
6. performed initial data processing for updating NWI maps for east-central Minnesota and northern Koochiching County.

Subsequent phases of this project are focused on producing updated NWI maps for five different regions of Minnesota; east-central, southern, northeastern, central-lakes, and northwestern. These subsequent phases will also include the continuation of the imagery acquisition for the southern, northeastern, and central-lakes regions.

Project Results Use and Dissemination
The wetland mapping standards and quality assurance objectives developed through this project are presented in reports found on the project website. Imagery acquired as part of this project are freely available to the public through the Minnesota Geospatial Information Office website. The imagery for northeastern Minnesota receives an average of about 62,000 requests per month and the imagery for east-central Minnesota receives an average of more than 300,000 requests per month. Wetland mapping procedures based on pilot studies in northeast and east-central Minnesota are contained in two separate reports. Three hard copies and one electronic copy on CD have been submitted with the final project report to LCCMR. Presentations and workshops have been provided by the University of Minnesota regarding the updated wetland mapping methods as described above.
 

Project Publications:
Comprehensive Project Plan for the National Wetland Inventory Update of Minnesota
Requirements for the National Wetland Inventory of Minnesota
Quality Assurance PRoject Plan for the National Wetland Inventory of Minnesota
Wetland Mapping Methods for the Twin Cities Metropolitan Area
Wetland Mapping Methods for the Arrowhead Region of Minnesota