Shell Lake Flow Control Feasibility Assessment
Why a Flow Control Structure?
The idea for a flow control at Shell Lake came to us in 2020 when we noticed a marked decline in young-of-the-year pike and speculated there was an apparent spawning failure of pike the previous year.
Analysis of environmental data collected at Shell Lake indicated that the water level had dropped 1.2 feet in 2019 and the drop was greater than any other year for which data was collected.
We have continued to see success with small pike harvests since 2020 and anticipate invasive pike can be controlled by managing the lake’s water level during pike spawning.
Download the Feasibility Study
Read the report on a future Shell Lake Flow Control project
Public Meeting
Listen to the recording of the July 3 meeting.
Potential Benefits
A flow control is a structure that alters the flow of water in a stream or from a lake. This structure maintains desired water levels for various reasons. They are passive devices that operate with minimal manual intervention.
Northern Pike Suppression
Aid in suppression of northern pike by managing water levels at critical pike spawning times.
Salmon Monitoring
Aid in the assessment of salmon populations
Migration
Assist adult salmon migration over seasonal barriers like beaver dams in Shell Creek.
Feasibility study at Shell Lake
We developed our idea for a flow control into a grant proposal, which was funded by the Alaska Sustainable Salmon Fund (AKSSF). During the summer of 2025, we completed the feasibility study with the assistance of a contracted engineering firm, HDR. We took HDR on a visit to Shell Lake in mid-June. Using existing data as well as data collected during the site visit, HDR prepared a report that includes formulating conceptual design alternatives to raise and lower the water level of the lake for the purpose of managing invasive pike.
Pike suppression efforts to date
We have used gillnets and hook-and-line harvesting since 2012 to suppress northern pike. This targeted suppression strategy has proven successful but does require continued annual operations and funding at Shell Lake. As of fall 2025, we have removed 7,851 invasive pike from Shell Lake. CIAA has funding from AKSSF to return a crew to Shell Lake through 2026.