A Water Management Plan was created in 2013 for the upper and lower segments of the Souhegan River. This plan was developed with water users, dam owners, and other interest groups. The plan applies the instream flow protections determined during the Protected Instream Flow Study. By maintaining the river's protected instream flows, the plan provides more resilient water supplies for water users and protects aquatic species and their habitat.
The Water Management Plan documents each water user's or dam owner's management actions. Management actions are taken after stream flows fall below defined thresholds for extended durations of time. Actions include water use management and conservation plans for affected water users, and dam management for select dam owners.
To track when management actions should be applied, NHDES developed an assessment tool that compares daily stream flow to protected flow criteria. The assessment tool (Current Souhegan Instream Flow Conditions, linked below) tracks the daily stream flows and describes conditions with respect to the protected instream flow criteria.
Water Management Plan (Established August 30, 2013)
- Souhegan Protected Instream Flows and Definitions
- Current upper Souhegan Instream Flow Conditions
- Current lower Souhegan Instream Flow Conditions
Real Time Data
- USGS 01094000 Souhegan River at Merrimack, NH
- USGS 01093852 Souhegan River (Site WLR-1) Near Milford, NH
- Souhegan Flood Control Dam (Site 19) Real Time Data
Protected Instream Flow Study (Established August 30, 2013)
- Designated River Information (Fact Sheet, Map, Nomination, Report, Plan)
- Souhegan River Watershed Biomonitoring Data 2004
Locations and Associated Data
Fish Data
Invertebrates Data
Map of Biomonitoring Locations
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