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08:24
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
Determinants of spatial and temporal patterns in compensatory wetland mitigation
Todd BenDor1, Nicholas Brozović
1Department of City and Regional Planning, University of North Carolina at Chapel Hill, CB #3140, New East Building, Chapel Hill, NC, 27599-3140, USA. bendor@email.unc.edu
Environmental Management
|July 3, 2007
Summary
Decreasing wetland mitigation thresholds have increased the use of mitigation banks, especially for small development projects. Local regulations may prioritize administrative over hydrologic boundaries for compensatory wetland mitigation.
Area of Science:
- Environmental Science
- Ecological Restoration
- Environmental Policy
Background:
- Wetland development projects often require compensatory mitigation through on-site or off-site creation or restoration.
- Federal support for third-party off-site mitigation has grown, alongside a decrease in the minimum impact size triggering mitigation requirements.
- Limited research exists on the aggregate impact of individual wetland mitigation projects or comparisons by regulatory agency or development size.
Purpose of the Study:
- To analyze the effects of decreasing mitigation thresholds on wetland mitigation methods and spatial distribution.
- To compare the choice of mitigation method by regulatory agency and development size.
- To assess the influence of local versus federal regulations on cross-watershed mitigation.
Main Methods:
- Analysis of 1058 locally and federally permitted wetland mitigation transactions in the Chicago region (1993-2004).
- Examination of trends in mitigation banking use relative to development size.
- Comparison of mitigation performance across watershed boundaries under local and federal regulations.
Main Results:
- Decreasing mitigation thresholds significantly impact mitigation methods and spatial distribution.
- Increased use of mitigation banking is primarily driven by small development impacts.
- Large developments rarely used mitigation banking and were less affected by regulatory changes; small developments may lack scale economies for permittee-responsible mitigation.
- Local regulations prohibiting cross-county mitigation resulted in more cross-watershed mitigation than federal regulations.
Conclusions:
- Regulatory changes and the growth of mitigation banking disproportionately benefit small development impacts.
- Local wetland mitigation regulations may prioritize administrative boundaries over hydrological function.
- Further research is needed to understand the long-term ecological outcomes of different mitigation strategies.
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