Grist Mill Pond Dam dam
Grist Mill Pond Dam
Grist Mill Pond Dam, located in Ashland, New Hampshire, stands as a testament to the state's commitment to hydroelectric power generation. Built in 1924, this concrete buttress dam stands at a height of 16 feet, with a length of 130 feet, and has a storage capacity of 175 acre-feet. The dam regulates the flow of the Squam River, serving as a critical piece of infrastructure for the region.
Despite its historical significance and essential role in energy production, the Grist Mill Pond Dam faces challenges in terms of maintenance and safety. A recent inspection in October 2019 revealed a poor condition assessment, with a high hazard potential. The dam's emergency action plan (EAP) is outdated, and there are concerns about its ability to meet current safety guidelines. These issues underscore the need for proactive risk management measures to ensure the dam's continued operation.
As water resource and climate enthusiasts, it is crucial to advocate for the necessary resources and support to address the maintenance and safety concerns surrounding the Grist Mill Pond Dam. By prioritizing investment in infrastructure upgrades, conducting regular inspections, and updating emergency response plans, we can protect both the dam and the surrounding communities from potential risks. The preservation of this historic dam is not only essential for energy production but also for the sustainable management of water resources in the region.
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 Grist Mill Pond Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pemigewasset River At Plymouth | 1,900 cfs | → |
| Smith River Near Bristol | 180 cfs | → |
| Baker River Near Rumney | 367 cfs | → |
| Winnipesaukee River At Tilton | 1,590 cfs | → |
| Merrimack River At Franklin Junction | 5,420 cfs | → |
| Bearcamp River At South Tamworth | 198 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Grist Mill Pond Dam.
Boat launches
- Squam Lake Public Boat Launch
- Winona Lake Boat Launch
- Mooney Clark Landing Road Bristol
- Wickwas Lake Boat Launch
- Kanasatka Lake Boat Launch
- Spectacle Pond Boat Launch
Campgrounds
Paddle runs
- Thornton Railroad Bridge To Bridgewater/Bristol Town Line
- Begins In Franklin To Sewall's Island
- Woodstock/Thornton Town Line To Thornton Railroad Bridge
- Sewall's Island To Manchester Street Bridge
- Headwaters At Profile Lake To Southern Boundary Of Franconia Notch State Park
Track Grist Mill Pond Dam 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 Grist Mill Pond Dam
Where does the data for Grist Mill Pond Dam 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 High 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 Grist Mill Pond Dam.