Hanover Reservoir Dam dam
Hanover Reservoir Dam
Hanover Reservoir Dam, located in Sprague, Connecticut, is a local government-owned structure that serves primarily for recreational purposes. Built in 1900, this Earth-type dam stands at a height of 26.5 feet and spans 750 feet in length, with a storage capacity of 400 acre-feet. The dam impounds the Little River, creating a surface area of 22 acres and covering a drainage area of 33.3 square miles.
Despite its historical significance, Hanover Reservoir Dam is currently rated as having a high hazard potential and poor condition assessment. The spillway, with a width of 147 feet, is uncontrolled, presenting potential safety risks. The dam's last inspection was conducted in November 2014, with a frequency of every two years, indicating a need for regular monitoring and maintenance to ensure the safety of the surrounding community.
Given its moderate risk rating and the importance of its recreational use, efforts should be made to address the dam's structural integrity and emergency preparedness. With its proximity to residential areas in New London County, it is crucial for Hanover Reservoir Dam to undergo necessary repairs and updates to mitigate potential risks and ensure the safety of both the dam and the community it serves.
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 Hanover Reservoir Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Little River Near Hanover | 42 cfs | → |
| Quinebaug River At Jewett City | 1,010 cfs | → |
| Shetucket River At Taftville | 1,070 cfs | → |
| Yantic River At Yantic | 101 cfs | → |
| Shetucket River Near Willimantic | 736 cfs | → |
| Natchaug River At Willimantic | 348 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Hanover Reservoir Dam.
Boat launches
- Jerusalem Road South Windham
- Butts Bridge Road Canterbury
- Lovell Lane 50, Canterbury
- Beaver Brook Pond
- Jeffrey Lane Griswold
- Pine Acres Lake
Campgrounds
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
- Begins Below The Tailrace Of The Lower Collinsville Dam To The Route 187 Bridge
- The Confluence With The Nepaug River To A Point 0.2 Miles Below The Lower Collinsville Dam Tailrace
- New Hartford/Canton Town Line To The Confluence With The Nepaug River
- The Massachusetts-Connecticut State Line In Hartland To The Confluence With The Salmon Brook Main Stem
Track Hanover Reservoir 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 Hanover Reservoir Dam
Where does the data for Hanover Reservoir 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 Hanover Reservoir Dam.