Upper Lake Dam dam
Upper Lake Dam
Upper Lake Dam, located in Yaphank, Suffolk County, New York, stands as a vital structure on the Carman River, serving primarily for recreational purposes since its completion in 1932. Managed by the local government, the dam boasts an earth design with a height of 8 feet and a length of 250 feet, offering a maximum storage capacity of 68 acre-feet. Despite its low hazard potential, the dam's spillway width of 8 feet allows for a maximum discharge of 35 cubic feet per second, ensuring effective water management during peak flow events.
State-regulated by the NYS DEC, Upper Lake Dam undergoes regular inspections, with the last recorded assessment in May 2009. While its condition remains unrated, the risk assessment categorizes the dam as moderate, emphasizing the need for proactive risk management measures. With its scenic location and modest surface area of 19 acres, the dam plays a crucial role in enhancing the local ecosystem and providing a recreational haven for residents and visitors alike. As climate change impacts water resources, the sustainable management of Upper Lake Dam will be pivotal in adapting to evolving hydrological patterns and safeguarding the surrounding environment for future generations.
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 Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Carmans River At Yaphank Ny | 15 cfs | → |
| Swan River At East Patchogue Ny | 12 cfs | → |
| Connetquot Bk Nr Central Islip Ny | 21 cfs | → |
| Peconic River At Riverhead Ny | 17 cfs | → |
| Nissequogue River Near Smithtown Ny | 31 cfs | → |
| Sampawams Creek At Babylon Ny | 9 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Upper Lake Dam.
Boat launches
Campgrounds
- Cathedral Pines County Park
- Southaven County Park
- Watch Hill Campgrounds
- Wildwood State Park
- Cupsogue County Park
- Blydenburgh Park
Fishing spots
Track Upper Lake 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 Upper Lake Dam
Where does the data for Upper Lake 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 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 Upper Lake Dam.