May Pond Dam dam
May Pond Dam
May Pond Dam, also known as Butterfields Pond Dam, is a state-owned structure located in Washington, New Hampshire. Built in 1830, this earth dam stands at a height of 14 feet and stretches 215 feet in length, impounding the waters of the Ashuelot River for recreational purposes. The dam has a storage capacity of 950 acre-feet, with a normal storage level of 465 acre-feet across a surface area of 158 acres.
Managed by the NHDES Dam Bureau, May Pond Dam has a state-regulated status with inspection, permitting, and enforcement protocols in place. Despite being classified as having a significant hazard potential, the dam's condition has been assessed as fair as of October 2016. With a moderate risk assessment rating, the dam is equipped with a 63-foot uncontrolled spillway and has a maximum discharge capacity of 1071 cubic feet per second. This historical structure continues to play a vital role in water resource management and recreation within 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 May Pond Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| North Branch River Near Antrim | 61 cfs | → |
| Contoocook River Near Henniker | 782 cfs | → |
| Ashuelot River Near Gilsum | 126 cfs | → |
| Sugar River At West Claremont | 431 cfs | → |
| Connecticut River At North Walpole | 11,900 cfs | → |
| Williams River Near Rockingham Vt | 144 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near May Pond Dam.
Boat launches
- Butterfield Pond Boat Launch
- Dodge Pond Boat Launch
- Long Pond Boat Launch
- Halfmoon Pond Boat Launch
- Millen Lake Boat Launch
- Sand Pond Boat Launch
Campgrounds
- Northstar Campground
- Fox Brook Tent Site
- Mile-Away Campground
- Tree Farm Campground
- Camp Wilmot
- Mt. Ascutney State Park
Paddle runs
- Begins In Franklin To Sewall's Island
- Sewall's Island To Manchester Street Bridge
- First Bridge Upstream On Route 100 To Confluence With West River
- Headwaters To First Bridge Upstream On Route 100
- Headwaters To Crossing Of Route 100 Near Route 155
- Headwaters To Confluence With West River (End Of Sherman Road)
Track May 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 May Pond Dam
Where does the data for May 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 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 May Pond Dam.