Sanborn Pond Grist Mill Dam dam
Sanborn Pond Grist Mill Dam
Sanborn Pond Grist Mill Dam, located in Loudon, New Hampshire, was completed in 1830 and serves multiple purposes, including fire protection and creating a stock or small fish pond. The dam, primarily made of earth with a buttress core, stands at a height of 16 feet and spans 265 feet in length. It has a storage capacity of 1,055 acre-feet and a drainage area of 4.6 square miles, with a normal storage level of 470 acre-feet.
Managed by a private owner, the dam is regulated by the New Hampshire Department of Environmental Services Dam Bureau, which oversees permitting, inspection, and enforcement activities. The dam's condition was assessed as "fair" in 2017, with a high hazard potential and a moderate risk rating. Despite its age, the dam continues to provide essential services while balancing the need for safety and risk management. Water resource and climate enthusiasts can appreciate the historical significance and ongoing maintenance efforts of the Sanborn Pond Grist Mill Dam in sustaining 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 Sanborn Pond Grist Mill Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Suncook River At North Chichester | 221 cfs | → |
| Soucook River | 22 cfs | → |
| Winnipesaukee River At Tilton | 1,610 cfs | → |
| Merrimack River At Franklin Junction | 4,850 cfs | → |
| Blackwater River Near Webster | 19 cfs | → |
| Warner River At Davisville | 348 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sanborn Pond Grist Mill Dam.
Boat launches
- Rollins Pond Boat Launch
- Lily Lake Boat Launch
- Suncook River Boat Launch
- Crooked Pond Boat Launch
- Lougee Pond Boat Launch
Campgrounds
- Camp Spaulding
- Saddleback Campground
- Green Tops Campground
- Remote Campsite
- Mile-Away Campground
- Old Stage Campground
Track Sanborn Pond Grist Mill 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 Sanborn Pond Grist Mill Dam
Where does the data for Sanborn Pond Grist Mill 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 Sanborn Pond Grist Mill Dam.