Skip to main content


1. Purpose

This guidance contains the requirements for submission of Section 26a requests for sub-impoundments.

2. Background

For the purpose of this guidance, sub-impoundments are defined as areas that retain water behind or upstream of a man-made structure (e.g., dam, berm, levee). These structures usually retain water above the normal operating level during reservoir drawdown periods, thereby creating small ponds or lakes. Sub-impoundments can contribute to natural resource management of TVA lands through the development and maintenance of wildlife habitats, wetlands, and dispersed recreation. However, they may negatively impact TVA reservoir operations, navigation, and flood control. Sub-impoundments may also potentially encourage residential development.   

While TVA generally does not approve the construction of sub-impoundments to facilitate private development, TVA will consider proposals that provide public benefit from government agencies. TVA has worked with state and federal agencies (e.g., Tennessee Wildlife Resources Agency, Alabama Department of Conservation and Natural Resources, and U.S. Fish and Wildlife Service [USFWS]) to develop sub-impoundments for natural resource management, such as those that create or enhance wildlife habitats.

Structures that create sub-impoundments are regulated under Section 26a of the TVA Act regardless of land rights (TVA fee-owned or flowage easement) at the site where the structure would be constructed. Permanent fill and grading is prohibited on TVA-owned residential access shoreland in accordance with Section 1304.209(a), and any structure built on land subject to a TVA flowage easement is considered an obstruction requiring review and approval by TVA, including fill placed in the flood control zone (Sections 1304.300 and 1304.303(b)). Additionally, TVA flowage easements contain specific rights regarding the prevention and removal of structures. 

3. Process

3.1 Sub-impoundments involving TVA land or land rights

A. Private Sub-impoundments

TVA will not approve requests to build structures that create sub-impoundments affecting TVA fee land or land rights (e.g., flowage easements) from private applicants regardless of intended use.  Such requests for private sub-impoundments may include, but are not limited to, requests to build sub-impoundments that facilitate private development (residential or otherwise) and requests to build sub-impoundments which create lakes or ponds on private property for the development and maintenance of wildlife habitats or wetlands. 

Private applicants requesting Section 26a permits for sub-impoundments should be advised that the application will be denied.  If an application is received, the Regional Watershed Office should offer to return the application and the fee to the applicant.  If the applicant requests a formal decision, the Regional Watershed Office should accept the application and inform the applicant the fee is non-refundable. Once denied, the applicant will have appeal rights. 

B. Public Sub-impoundments

TVA may consider requests from state and federal agencies to build structures to create sub-impoundments for natural resource management that provide public benefits and resource user benefits. Such requests may include, but are not limited to, sub-impoundments that create wildlife habitats, wetlands, or dispersed recreation opportunities. These requests may be considered when TVA determines that: (1) the project aligns with TVA’s current stewardship programmatic objectives; (2) the project provides public benefits and resource user benefits; and (3) the requesting agency is willing to pay the full administrative costs of the project review and the cost of the project construction, operation, and maintenance.

These projects must also meet the following criteria (additional criteria may be required, as TVA deems necessary):

  • The project is submitted and developed by one or more public agencies, either state or federal.
  • Applicant signs an agreement to pay all TVA administrative costs, including, but not limited to, environmental review, surveying, legal document preparation, project management, and other related costs.
  • Applicant signs an agreement to bear responsibility for all long-term operation and maintenance costs.
  • Applicant agrees to any project modifications required by TVA to minimize the impact on lost flood control storage.
  • Applicant provides the necessary documentation to ensure that downstream damages resulting from failure of the sub-impoundment structure would be minor and all upstream flooding impacts would be contained on property the applicant either owns in fee or has flowage easements over. Applicant is responsible for all costs associated with any damage and repair due to failure of the sub-impoundment. If TVA land is involved, the instrument will include a condition stating the same.
  • Land surrounding the entire water's edge must be public land. The Section 26a permit will include a condition that access rights can only be provided for the use of the general public; no access rights can be provided to adjacent individual or community property owners now or in the future. If any land surrounding the water's edge is later transferred to private ownership, the condition of the permit remains--no private access (individual or community) will be granted, and access originally provided for use by the general public must be maintained.
  • Proposed project will be phased, following a general schedule as follows:
    1. Applicant submits project justification and description, including drawings showing horizontal limits of construction and elevations, to TVA for initial review.
    2. TVA communicates to applicant the requirements listed above for the project.
    3. If TVA decides further consideration is warranted and applicant agrees to the above requirements, TVA will notify the applicant that a complete application is needed, which may include, but is not limited to:
      • Letter from USFWS stating support of project.
      • Letter from the state agencies responsible for managing natural resources and water quality certification stating support of project.
      • Letter from the state historic preservation officer stating that the project requires no further cultural review.
      • Letter from relevant tribal authorities stating that the project requires no further cultural review.
      • Commitment letter to pay full administrative costs.
      • Disclosure of funding sources and participants in project.
      • Any other agreements between applicant and others concerning the project

3.2 Off-reservoir impoundments

Off-reservoir impoundments of water on streams or drainage areas away from the reservoir (completely above June 1 flood guide elevation) where TVA has no fee land or flowage rights are not covered by this guideline.