Gregg Falls dam
Gregg Falls
Gregg Falls, also known as Glenn Lake Dam, is a captivating hydroelectric structure located in Pinardville, New Hampshire. Built in 1917, this dam stands at a height of 66 feet and has a length of 1360 feet, with a storage capacity of 3650 acre-feet. Its primary purpose is hydroelectric power generation, while also serving for fire protection, stock, small fish pond, and recreation purposes.
Managed by the New Hampshire Department of Environmental Services Dam Bureau, Gregg Falls is regulated and inspected regularly to ensure its safety and compliance with state laws. With a high hazard potential due to its location on the Piscataquog River, the dam poses a moderate risk and is equipped with uncontrolled spillways and slide gates for water management. Despite its age, Gregg Falls continues to play a vital role in the local water resource management and contributes to the region's energy infrastructure.
As a significant landmark in Hillsborough County, Gregg Falls represents a blend of history, technology, and environmental stewardship. With its gravity, earth, and concrete construction, the dam symbolizes the intersection of human ingenuity and natural resources, showcasing the importance of sustainable water management practices. For water resource and climate enthusiasts, Gregg Falls serves as a reminder of the crucial role that infrastructure plays in shaping our relationship with the environment and the need for ongoing monitoring and maintenance to ensure its longevity and safety.
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 Gregg Falls -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Piscataquog River Near Goffstown | 137 cfs | → |
| South Branch Piscataquog River Near Goffstown | 127 cfs | → |
| Piscataquog River Bl Everett Dam | 8 cfs | → |
| Merrimack R Nr Goffs Falls | 8,350 cfs | → |
| Souhegan River At Merrimack | 235 cfs | → |
| Souhegan River (Site Wlr-1) Near Milford | 168 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Gregg Falls .
Boat launches
- Piscataquog River (Glen Lake) Boat Launch
- Kimball Pond Boat Launch
- Gorham Pond Boat Launch
- Bailey Pond Boat Launch
- Heritage Trail Bedford
- Mount William Pond Boat Launch
Campgrounds
- Mile-Away Campground
- Camp Spaulding
- Windham Town Forest Tent Platforms
- Remote Campsite
- Saddleback Campground
- Camp Wanocksett
Paddle runs
Track Gregg Falls 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 Gregg Falls
Where does the data for Gregg Falls 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 Gregg Falls .