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Compensatory Mitigation for Streams and Wetlands


Commercial, residential and agricultural land development, construction of linear transportation and utility systems, and other activities requiring State and Federal permits have the potential to impact and degrade Tennessee’s streams. These impacts often result in loss of aquatic resource values, including stream length, hydrology, available habitat, species composition, and other beneficial ecological and physical characteristics. Mitigation for certain stream impacts in Tennessee have been required since the passage of the Tennessee Water Quality Control Act by the Tennessee General Assembly in 1977. In July 2000, the Tennessee Water Quality Control Board adopted rules that more clearly specified the requirement that permits for the alteration of streams must not result in a net loss of water resource value, and established mitigation requirements. These Rules were further revised by the Board in October 2018.

The U.S. Army Corps of Engineers (USACE) and Tennessee Department of Environment and Conservation (TDEC) Division of Water Resources (Division) currently require compensatory mitigation for certain permitted impacts to Tennessee's streams. The Division may require compensatory mitigation to off-set unavoidable adverse impacts resulting in an appreciable permanent loss of aquatic resource value. The Division cannot issue an individual ARAP, with or without mitigation, unless an applicant has first demonstrated that there are no practicable alternatives to the proposed activity that would have less adverse impact on resource values, so long as the alternative does not have other significant adverse environmental consequences.

This page contains useful information for applicants who need access to the 2019 Stream Mitigation Guidelines, the TN Debit Tool, and other resources such as the TN Stream Quantification Tool, statewide, ecoregionally based regional curves, and other documents needed to prepare compensatory mitigation projects.

For large, complex proposals, applicants seeking a Tennessee Department of Environment and Conservation (TDEC) Aquatic Resource Alteration Permit (ARAP)/Section 401 Water Quality Certification and a U.S. Army Corps of Engineers (USACE) Clean Water Act Section 404 Permit can request a regulatory coordination meeting, especially those in which permittee-responsible mitigation (PRM) is proposed. If you have a project proposal that you think may meet these requirements please visit our regulatory coordination page to obtain additional information. 

  • The US Army Corps of Engineers Compensatory Mitigation Public Facing Mapviewer Database
    RIBITS (Regulatory In lieu fee and Bank Information Tracking System) was developed by the U.S. Army Corps of Engineers with support from the Environmental Protection Agency, the U.S. Fish and Wildlife Service, the Federal Highway Administration, and NOAA Fisheries to provide better information on mitigation and conservation banking and in-lieu fee programs across the country. RIBITS allows users to access information on the types and numbers of mitigation and conservation bank and in-lieu fee program sites, associated documents, mitigation credit availability, service areas, as well information on national and local policies and procedures that affect mitigation and conservation bank and in-lieu fee program development and operation.
  • TDOT Environmental Mitigation Office
    Compensatory mitigation is required for certain TDOT transportation projects, as part of the permitting process through the Tennessee Department of Environment and Conservation (TDEC) and the U.S. Army Corps of Engineers (USACE). The Tennessee Department of Transportation (TDOT) Environmental Mitigation Office is responsible for providing compensatory mitigation to offset unavoidable stream and wetland impacts from transportation projects through a process referred to as compensatory mitigation.
  • Cumulative Impacts and the Common Plan of Development
    TDEC regulations require the Division to evaluate…” whether the proposed activity is reasonably likely to have cumulative or secondary impacts to the water resource” for linear and non-linear projects. Where a single impact of a given scale might only require coverage under a general permit, multiple impacts of the same scale may require coverage under an individual permit, due to the cumulative effects. Similarly, large linear and non-linear activities often encompass multiple impacts that may, collectively, result in a net loss of water resource value if compensatory mitigation is not utilized to offset or compensate for the impacts. Therefore, TDEC must review applications from larger linear and non-linear activities that propose multiple impacts comprehensively at the outset of permitting to ensure that there is no net loss of resource value from individual or cumulative impacts. These projects are considered Common Plans of Development (CPD).
  • Regional Curves
    TDEC Division of Water Resources has worked (and continues to work) with Jennings Environmental, LLC to develop ecoregion based regional curves across the entire state. These regional curves were developed to assist practitioners in identifying the bankfull stage in ungaged watersheds and estimating the bankfull discharge and dimensions for river studies and natural channel designs. Regional curves relate bankfull channel dimensions (i.e., width, depth and cross-sectional area) and discharge to watershed drainage area. These tools can also be used as an aid in designing a pilot or low flow channel within flood control projects. TDEC Regional curves should only be applied where the project reach has the same Level III Ecoregion as the reaches that were used to generate the curve.
  • Tennessee Stream Quantification Tool Version 0.9 Public Notice Webinar (Jan 17, 2018)
  • Stream Permittee-Responsible Mitigation Guidance
  • Stream (Draft) Prospectus Checklist
  • Wetland Permittee-Responsible Mitigation Guidance
  • Wetland (Draft) Prospectus Checklist
Long term protection for compensatory mitigation sites is a requirement of federal rule and of Tennessee's Section 401 Water Quality Certifications and Aquatic Resource Alteration Permits. The following reference documents should be used to fulfill the site protection instrument requirements:
 

Water
Contacts

Jimmy Smith

Natural Resources Unit Manager
615-532-0648
Jimmy.R.Smith@tn.gov