Upper Ansonia Reservoir East Dike dam
Upper Ansonia Reservoir East Dike
Upper Ansonia Reservoir East Dike, also known as Upper Derby Hill Reservoir, is a masonry dam located in Derby, Connecticut, owned by the local government and regulated by the Department of Energy and Environmental Protection (DEEP). The dam stands at a height of 12 feet and stretches 345 feet in length, with a fair condition assessment as of May 2017. The reservoir has a high hazard potential, with an inspection frequency of every 2 years to ensure public safety.
Situated in New Haven County, Upper Ansonia Reservoir East Dike serves as a crucial water resource for the region, although its normal storage capacity is listed as zero. The dam has no spillway and associated structures, with no outlet gates identified. While the dam was last inspected in August 2015, there is no information available on the year of completion or the purposes of the reservoir. Despite its fair condition, the dam's hazard potential underscores the importance of regular inspections and maintenance to prevent potential risks.
As climate and water resource enthusiasts delve into the details of Upper Ansonia Reservoir East Dike, its significance in the local water management system becomes apparent. With a high hazard potential and fair condition, the dam's role in providing water storage and flood control underscores the need for continued monitoring and management to ensure its structural integrity and public safety. As a key infrastructure in the region, the reservoir's upkeep and regulatory oversight by DEEP reflect the ongoing efforts to safeguard water resources in Connecticut and mitigate potential risks associated with dam failures.
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 Upper Ansonia Reservoir East Dike -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Housatonic River At Stevenson | 495 cfs | → |
| Naugatuck River At Beacon Falls | 657 cfs | → |
| Mill R Nr Hamden | 54 cfs | → |
| Rooster River At Fairfield | 10 cfs | → |
| Pootatuck R At Sandy Hook | 43 cfs | → |
| Pomperaug River At Southbury | 121 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Upper Ansonia Reservoir East Dike.
Boat launches
- Lake Housatonic
- Huntington Street Shelton
- Main Street Hamden
- Shipyard Lane Milford
- April Street 3, West Haven
- Housatonic River State Boat Launch
Campgrounds
Fishing spots
- Lake Housatonic
- Picketts Pond
- Quillinan Reservoir
- Fountain Lake Reservoir
- Lake Wintergreen
- Isinglass Reservoir
Paddle runs
- Begins Downstream Of The Borough Of Bantam, At Stoddard Road Bridge To The Confluence With The Shepaug River
- Pond Downstream Of Shepaug Reservoir Dam, Marked By Service Road Bridge To Ends In Backwaters Of Lake Lillinonah, Near Roxbury Falls
- Begins Below The Tailrace Of The Lower Collinsville Dam To The Route 187 Bridge
- Kent Bridge To Boardman 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
Track Upper Ansonia Reservoir East Dike 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 Upper Ansonia Reservoir East Dike
Where does the data for Upper Ansonia Reservoir East Dike 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 Upper Ansonia Reservoir East Dike.