Harris Pond Dam dam
Harris Pond Dam
Harris Pond Dam, located in Nashua, New Hampshire, is a privately owned structure regulated by the NHDES Dam Bureau. Built in 1870, this Earth-type dam stands at a height of 35 feet and spans 450 feet across Pennichuck Brook. Its primary purpose is water supply, with a storage capacity of 1,670 acre-feet and a drainage area of 25 square miles.
With a spillway width of 85 feet and a maximum discharge of 5,414 cubic feet per second, Harris Pond Dam is classified as having a high hazard potential. Despite this, the dam is currently in satisfactory condition as of the last assessment in November 2015. Regular inspections are conducted, with the most recent one taking place in June 2020, demonstrating a commitment to ensuring the safety and integrity of this vital water resource infrastructure.
While the risk assessment for Harris Pond Dam indicates a moderate level of risk, management measures and emergency action plans are not explicitly noted in the available data. As water supply remains a critical function of the dam, continued monitoring and maintenance will be key to preserving its functionality and safeguarding the surrounding community from potential hazards.
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 Harris Pond Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Souhegan River At Merrimack | 256 cfs | → |
| Beaver Brook At North Pelham | 35 cfs | → |
| Nashua River At East Pepperell | 531 cfs | → |
| Merrimack R Nr Goffs Falls | 9,610 cfs | → |
| Souhegan River (Site Wlr-1) Near Milford | 181 cfs | → |
| Merrimack River Bl Concord River At Lowell | 11,800 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Harris Pond Dam.
Boat launches
- Greeley Ramp Road Nashua
- Naticook Lake Boat Launch
- Claveau Landing
- Winchester Street Boat Launch
- Flints Pond Boat Launch
- Robinson Pond Boat Launch
Campgrounds
- Windham Town Forest Tent Platforms
- Grotonwood
- Pearl Hill Campground
- Damon Pond Campground
- Camp Evergreen
- Remote Campsite
Paddle runs
Track Harris 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 Harris Pond Dam
Where does the data for Harris 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 Harris Pond Dam.