Dennys River Instream Flow Study

Project Name: Dennys River Management Plan

Summary: Flow study recommends optimum flows for Atlantic salmon

Client: Maine Department of Marine Resources

Project Location: Dennys River, Downeast ME

Project Size: 132 square miles

Services Provided:
•  Endangered Species Act Consulting
•  Instream Flow Incremental
    Methodology (IFIM) Study
•  Aquatic Habitat Assessment
•  Hydrologic Analysis

Project Timeframe:
2001 - 2003

Relationship with Client: Since 1998

Client Needs:
The Maine Dept. of Marine Resources (MDMR) is responsible for protection, restoration, and management of Atlantic salmon throughout Maine, and also works with federal agencies on the federal recovery plan for Maine’s endangered Atlantic salmon. The MDMR commissioned a study to provide data to better protect critical spawning and rearing habitat throughout the Dennys River watershed, manage flow releases from a headwater dam, and develop a quantitative habitat based water management strategy based on an Instream Flow Incremental Methodology (IFIM) model.
Kleinschmidt Solution:
Kleinschmidt develop a watershed-scale IFIM model to evaluate flow changes to critical habitat, performing all field surveying, and mapping the cross section geometry. Kleinschmidt’s hydraulic and biologic computer modeling calculated the relationship between river flows and optimal salmon habitat that was used to make recommendations for flow management in the watershed, including controlled releases from a dam at the outlet of Meddybemps Lake. Kleinschmidt developed outflow rating tables for the gate and fish ladder at the headwater lake that controlled most of the mainstream flow. The results of the IFIM were used with historic flow data and the water budget to recommend a revised rule curve for Meddybemps Lake that optimizes flows for Atlantic salmon in the Dennys River and provide minimum flows even during drought. The hydrologic model results have also been used to manage water withdrawals in the Dennys River watershed. Kleinschmidt’s instream flow and lake management study was summarized in a report that is publicly available through the MDMR website at
Client Benefits:
Kleinschmidt’s report has been useful to natural resource agencies, non-profit organizations and private entities for managing instream flows and water withdrawals in a protected watershed and protecting an endangered fish population.