Dayville Emergency Spillway dam
Dayville Emergency Spillway
Dayville Emergency Spillway, also known as Pond 'A' Spillway, is a private-owned structure located in Dayville, Connecticut. Built in 1925, this masonry dam serves the primary purpose of hydroelectric power generation along the Five Mile River. With a dam height of 8 feet and a length of 37 feet, it has a storage capacity of 93 acre-feet and a maximum discharge of 2640 cubic feet per second.
Managed by the Federal Energy Regulatory Commission, the Dayville Emergency Spillway has a low hazard potential and a moderate risk assessment rating. Although not state-regulated, it undergoes periodic inspections every three years to ensure its structural integrity and safety. The spillway, designed as uncontrolled, has a width of 37 feet and is associated with two other structures in the area.
While the spillway currently poses a moderate risk level, its management measures and emergency action plans are critical in mitigating potential hazards. With its historical significance and vital role in hydroelectric power generation, maintaining the integrity of the Dayville Emergency Spillway is essential for ensuring the safety and sustainability of 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 Dayville Emergency Spillway -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Quinebaug River At Putnam | 491 cfs | → |
| Little River At Harrisville | 38 cfs | → |
| Quinebaug R At West Thompson | 319 cfs | → |
| French R At N Grosvenordale | 125 cfs | → |
| Ponaganset River At South Foster | 7 cfs | → |
| Quinebaug River At Quinebaug | 244 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Dayville Emergency Spillway .
Boat launches
- Hartford Pike Rogers
- North Road 1060, Killingly
- Squaw Rock Road Killingly
- Clarkville Pond
- Quaddick Reservoir
- Bowdish Reservoir
Campgrounds
- George Washington State Campground
- Dyer Woods Nudist Campgrounds
- Narragansett Council, Boy Scouts Of America, Cub World
- Brialee
- Highland Campground
- Wilderness Lake Campground
Fishing spots
Paddle runs
- Begins Below The Tailrace Of The Rainbow Dam To The Confluence With The Connecticut River
- The Confluence Of The East And West Branches To The Confluence With The Farmington River In East Granby
- The Massachusetts-Connecticut State Line In Hartland To The Confluence With The Salmon Brook Main Stem
- Begins Below The Tailrace Of The Lower Collinsville Dam To The Route 187 Bridge
- The Hartland Headwaters To The Confluence With The Salmon Brook Main Stem
- The Confluence With The Nepaug River To A Point 0.2 Miles Below The Lower Collinsville Dam Tailrace
Track Dayville Emergency Spillway 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 Dayville Emergency Spillway
Where does the data for Dayville Emergency Spillway 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 Low 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 Dayville Emergency Spillway .