South Berwick dam
South Berwick
South Berwick, also known as the Salmon Falls River Dam No.1, is a privately owned hydroelectric dam located in New Hampshire. Built in 1923, this concrete gravity dam stands at 18 feet tall and spans 290 feet in length. It has a storage capacity of 641 acre-feet and serves the primary purpose of generating hydroelectric power. The dam is regulated by the New Hampshire Department of Environmental Services Dam Bureau and inspected by the Federal Energy Regulatory Commission.
This dam on the Salmon Falls River has a low hazard potential and a moderate risk assessment rating. It features an uncontrolled spillway with a width of 220 feet and two slide (sluice gate) outlet gates. The surrounding area has a surface area of 58 acres and a drainage area of 235 square miles. Despite its age, the dam has not undergone any recent condition assessments, but it is subject to regular inspections and enforcement to ensure its structural integrity and safety for the community.
South Berwick plays a crucial role in the local water resource management and climate resilience efforts, providing clean energy and flood control benefits to the region. With its historical significance and ongoing operational importance, this hydroelectric dam serves as a key infrastructure asset in the state's renewable energy portfolio and water resource management strategy. As enthusiasts of water resources and climate change, it is vital to monitor and support the sustainable operation of dams like South Berwick to ensure a resilient and environmentally friendly future for generations to come.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around South Berwick -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Isinglass R At Rochester Neck Rd | 53 cfs | → |
| Cocheco River Near Rochester | 97 cfs | → |
| Oyster River Near Durham | 11 cfs | → |
| Lamprey River Near Newmarket | 119 cfs | → |
| Winnicut River At Greenland | 17 cfs | → |
| Mousam River Near West Kennebunk | 225 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near South Berwick .
Boat launches
- Salmon Falls River Boat Launch
- Dover Eliot Road South Berwick
- Willand Pond Boat Launch
- Cathy Schiro O'Brien Cross Country Running Trail Dover
- Piscataqua River Boat Launch
- Oyster River Boat Launch
Campgrounds
- Old Stage Campground
- Saddleback Campground
- Remote Campsite
- Tidewater Campground
- Ferry Beach Campground
- Salisbury State Park Reservation
Paddle runs
Track South Berwick in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About South Berwick
Where does the data for South Berwick come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Low hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of South Berwick .