On February 23, 2018, U.S. Army Corps of Engineers (USACE) released a Public Notice detailing the requirement to use the Ohio Stream and Wetland Valuation Metric (SWVM). The SWVM is used to analyze a stream’s baseline condition while also tracking the progression of any projected physical, chemical and/or biological functional lift achieved through compensatory mitigation. Historically, impacts and mitigation were evaluated based on linear feet and credit ratios. A wetlands assessment tool is also under development and will be released at a later date.
Per the Public Notice, USACE will require the use of the SWVM to evaluate stream impacts and compensatory mitigation in the following scenarios:
- For projects seeking a Section 404 Individual Permit that is public noticed by the Corps.
- For proposed stream mitigation banks or in-lieu fee program stream mitigation sites.
- When the Corps determines that compensatory stream mitigation is required for a project.
- When a project exceeds the Nationwide Permit stream impact limitation thresholds.
The SWVM incorporates a variety of information and data, including: proposed stream impacts; stream habitat and biological data; and corresponding stream mitigation evaluations. This information is compiled in a spreadsheet and an Index Score is generated. The Index Score is used to calculate necessary debits/credits for stream mitigation.
The additional evaluations and studies for streams that may be impacted may include:
- Hydrogeomorphic assessments
- Water quality indicators
- Macroinvertebrate community studies
Due to the requirement of these additional studies, ecological evaluation costs will increase and mitigation fees will likely be higher for a development project involving stream impacts.