Induced fish movement over lowhead dams | W81EWF 21 SOI 0018

FAQs: Induced fish movement over lowhead dams (W81EWF 21 SOI 0018)

What is the purpose of the "Induced fish movement over lowhead dams" grant opportunity?

The opportunity supports research to test whether planned, short-term increases in river flow can improve fish passage past two aging lock-and-dam structures (Lock and Dam 2 and Lock and Dam 3) on North Carolina's Cape Fear River.

What core idea is being tested by this project?

The project tests whether environmental flow releases from Jordan Dam, timed to the spring spawning migration period, can mimic natural spring flood conditions. If river stage rises enough during these managed releases, the low-head structures at Locks and Dams 2 and 3 may become submerged, potentially letting migratory fish pass upstream over the structures rather than depending on lock operations.

Which river and structures does the project focus on?

The work focuses on North Carolina's Cape Fear River, specifically the barriers created by Lock and Dam 2 and Lock and Dam 3.

Why is fish passage at Locks and Dams 2 and 3 a concern now?

Fish passage has historically been supported at times through "conservation locking," where locks were operated specifically to help fish move upstream during spring migrations. However, Locks and Dams 2 and 3 are no longer used for commercial navigation and have continued to degrade, making routine lock-based fish passage increasingly limited and less feasible.

What are "environmental flow releases" in the context of this project?

Environmental flow releases are planned, short-term releases of water (here, from Jordan Dam) intended to create river conditions that resemble natural spring floods. The goal is to raise river stage and discharge during the migration period to improve passage opportunities.

How could increased river flow help fish move past these low-head dams?

If the managed releases raise the river stage enough to submerge the low-head structures at Lock and Dam 2 and Lock and Dam 3, fish may be able to pass upstream by moving over the structures during higher water conditions, instead of relying on lock operations.

Which fish species are being tracked in the study?

The study focuses on two diadromous species: American Shad (Alosa sapidissima) and Striped Bass (Morone saxatilis).

What does "diadromous" mean, and why does it matter here?

Diadromous fish move between saltwater and freshwater as part of their life cycle. For these species, access to upstream spawning habitat can be a limiting factor for population recovery, so barriers like dams and lock-and-dam structures can reduce successful migration to spawning areas.

What research method is central to this project?

Acoustic telemetry is central to the project. This approach uses implanted or attached acoustic tags on individual fish and a network of underwater receivers to record where and when tagged fish move through the river.

What kinds of data will acoustic telemetry produce for this project?

The telemetry system is intended to generate detailed, individual-level movement information, including when tagged fish arrive near the structures, how they behave around the barriers, and whether and when they successfully pass upstream.

What is meant by "passage efficiency" in this opportunity?

Passage efficiency refers to how often fish that reach the dams are able to get past them, and how that success changes under different flow conditions, particularly during the managed flow releases.

What are the main objectives of the anticipated work?

The anticipated work is organized around three main objectives: (1) quantify arrival timing and behavior of fish at Locks and Dams 2 and 3 and determine whether they pass upstream; (2) link movement and passage outcomes to environmental conditions, especially discharge and flow changes associated with managed releases, to see whether the flow regimen measurably alters behavior and passage success; and (3) test whether individual fish characteristics (such as size, sex, or condition) interact with environmental variables (such as flow and water temperature) to influence passage outcomes.

What fish behaviors will the project examine near the structures?

The project will examine behaviors such as milling around near the structures, making repeated passage attempts, turning back, and successfully passing upstream.

Which environmental conditions are specifically mentioned as important to analyze?

The opportunity highlights discharge and flow changes tied to managed releases, and also notes environmental variables such as water temperature in evaluating how conditions may influence passage outcomes.

Will the project look at differences among individual fish?

Yes. The third objective includes testing whether fish characteristics like size, sex, and overall condition interact with environmental variables like flow and water temperature to influence passage success.

How is this project connected to prior work in other river systems?

The project plans to apply telemetry approaches similar to those used by Auburn University and the U.S. Army Corps of Engineers in prior work on the Alabama River, but in a different river system (Cape Fear River), with different species and passage structures.

Who is offering this funding opportunity?

This is a discretionary funding opportunity offered by the Department of Defense, Department of the Army, U.S. Army Corps of Engineers.

What is the CFDA number listed for this opportunity?

The CFDA number provided is 12.630.

What type of award is expected?

The opportunity is expected to be awarded as a cooperative agreement.

What is the opportunity number?

The opportunity number is W81EWF 21 SOI 0018.

How many awards are anticipated and what is the funding limit?

The opportunity lists a single anticipated award with an award ceiling of $25,000.

What were the dates associated with this opportunity as listed?

The information provided lists a creation date of April 21, 2021, and an original application closing date of June 18, 2021.

How does this work relate to activities planned in 2021?

The work is framed as a collaborative effort tied to a 2021 implementation of environmental flow releases led by the USACE Wilmington District in partnership with The Nature Conservancy.

What is the broader purpose behind testing flow-based fish passage?

The broader purpose is to help restore access to historical upstream spawning grounds by using managed hydrology to overcome structural barriers, potentially providing an alternative to lock-based passage that has become less feasible as infrastructure deteriorates.

What role do the lock operations play in fish passage, and why look for alternatives?

Lock operations have previously been used for fish passage through conservation locking, but because the structures are degrading and no longer support commercial navigation, routine lock-based passage is becoming increasingly limited. The project evaluates whether managed flow releases can create a more practical, naturalistic pathway upstream.