Wiswall Dam dam
Wiswall Dam
Wiswall Dam, also known as Packers Falls Dam, is a concrete structure located in Durham, New Hampshire, along the Lamprey River. Built in 1911, this dam serves primarily for recreational purposes, providing a surface area of 27 acres for outdoor activities. With a height of 22 feet and a length of 400 feet, Wiswall Dam has a capacity of 500 acre-feet, with a normal storage level of 134 acre-feet.
Managed by the NHDES Dam Bureau, Wiswall Dam is inspected regularly to ensure its structural integrity and safety. The dam is classified as having a significant hazard potential, with a moderate risk assessment rating. Despite this, the condition assessment in 2017 deemed the dam to be in satisfactory condition. The spillway of Wiswall Dam is uncontrolled, with a width of 167 feet to handle maximum discharge flows of up to 12,630 cubic feet per second.
Water resource and climate enthusiasts will find Wiswall Dam to be an interesting site due to its historical significance, recreational purpose, and the management efforts put in place to ensure its safety and functionality. As a key feature along the Lamprey River, this dam plays a crucial role in regulating water flow and providing opportunities for outdoor recreation in the area. With ongoing inspections and risk assessments, Wiswall Dam is a focal point for understanding the intersection of infrastructure, water resource management, and environmental stewardship in New Hampshire.
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 Wiswall Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Lamprey River Near Newmarket | 137 cfs | → |
| Oyster River Near Durham | 13 cfs | → |
| Winnicut River At Greenland | 22 cfs | → |
| Isinglass R At Rochester Neck Rd | 66 cfs | → |
| Exeter River At Haigh Road | 57 cfs | → |
| Cocheco River Near Rochester | 117 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Wiswall Dam.
Boat launches
- Piscassic River Boat Launch
- Lamprey River Boat Launch
- Oyster River Boat Launch
- Squamscott River Boat Launch
- Great Bay Boat Launch
Campgrounds
- Old Stage Campground
- Remote Campsite
- Saddleback Campground
- Tidewater Campground
- Salisbury State Park Reservation
- Windham Town Forest Tent Platforms
Paddle runs
Track Wiswall 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 Wiswall Dam
Where does the data for Wiswall 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 Significant 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 Wiswall Dam.