Onsite mitigation in Waukesha County

​​Thompson & Associates Wetland Services

1514 Menomonee Ave, South Milwaukee, WI 53172

Phone: 414.571.8383

​​What is Mitigation?

Wetland mitigation was adopted by the state of Wisconsin in 2002, and modified since then. The process of mitigation is to require newly restored wetlands to replace impacted wetlands. The Wisconsin DNR permitting process, under NR 103, requires every effort be made to avoid wetlands on site. If wetlands cannot be avoided then the impact to wetlands must be minimized. Minimization includes narrowing or moving a road, putting in a retaining wall, and/or moving structures to impact the least amount of wetland. Very minor wetland impacts permitted by a WDNR General Permit do not require Mitigation but mitigation is now mandatory for any wetland impact permitted with a Wisconsin DNR Individual Permit. The DNR has developed Guidelines for Mitigation, and have many criteria for approving a mitigation plan. Currently the preferred method of mitigation is for the permittee (the entity responsible for the project) to purchase credit at a state approved wetland mitigation bank. If no wetland mitigation bank is available with credits to purchase then the permittee may purchase credits that are termed “in-lieu fee” compensation. Finally a small number of projects may be eligible for what used to be termed “on-site” mitigation- a small restoration project that compensates for wetland loss locally.
Read about wetland compensatory mitigation on the Wisconsin DNR site: http://dnr.wi.gov/topic/Wetlands/Mitigation/