Wetland Mitigation in Abandoned Gravel Pits

Thumbnail Image

Persistent link to this item

View Statistics

Journal Title

Journal ISSN

Volume Title


Wetland Mitigation in Abandoned Gravel Pits

Published Date



Minnesota Department of Transportation




It is becoming increasingly difficult to provide on-site mitigation for wetland impacts due to road construction in northeastern Minnesota counties that retain greater than 80 percent of their pre-settlement wetlands. Abandoned gravel pits are one of the few remaining areas that can serve as wetland mitigation sites. The overall goal of the project is to develop cost-effective methods for creating functional mitigation wetlands on abandoned gravel pit sites to compensate for wetland impacts due to road construction. Two approximately 1-hectare wetland creation demonstration sites were established in adjacent abandoned gravel pits within the U.S. Trunk Highway 53 reconstruction corridor to evaluate techniques for wetland establishment. Wet meadow and shrub swamp wetlands were attempted on one site, and wooded swamp and bog wetlands on the other. Wetland seed mixes provided both positive and negative effects on the developing plant communities on both sites initially but their effect was limited to the first year. Alder thicket and bog donor soil applications had positive effects but not until the third year of the study. Hardwood willow cuttings were effective for establishing a shrub component. Conifer seedlings did not survive unless planted on soil mounds. Fertilizer proved ineffective for promoting wetland plant growth during the study period. The use of straw mulch is questionable on saturated wetland sites such as those in this study.


Related to




Series/Report Number

Funding information

Minnesota Department of Transportation, Research Services Section

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Johnson, Kurt W.. (2010). Wetland Mitigation in Abandoned Gravel Pits. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/150618.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.