Buffer Mapping Project

Buffer Mapping Project

Minnesota's Buffer Protection Map

Minnesota's buffer law establishes new perennial vegetation buffers of up to 50 feet along rivers, streams and ditches that will help filter out phosphorus, nitrogen and sediment. The law provides flexibility and financial support for landowners to install and maintain buffers.

The DNR's role in Minnesota's buffer law is to produce and maintain a map of public waters and public ditch systems that require permanent vegetation buffers. The DNR released the buffer protection map in July 2016. The map is helping to guide the implementation of Minnesota's buffer law by landowners, with the help of the Board of Water and Soil Resources (BWSR), Soil and Water Conservation Districts (SWCDs), Drainage Authorities and other local governments.

How was the map made?

With the help of a wide range of professionals inside and outside the agency, the DNR combined existing public water inventory data, shoreland classification data and public ditch data to produce the map. The DNR used an extensive public and professional review process to produce the map.

How is buffer protection map being used?

The map is now being used for implementation. It helps landowners determine where buffers or alternative water quality practices are required and what buffer widths are required.

The map labels public ditches as requiring a 16.5-foot buffer (local ordinances may require wider buffers).
The map labels public waters as requiring a 50-foot average buffer (local ordinances may require wider buffers).
The map also labels a few sites as "needing field review." The DNR is organizing on-site verification of these public water features and will change this temporary label as they are verified.
The DNR excluded some public water wetlands from the map.