Denley dam
Denley
Denley, a hydroelectric dam located in Port Leyden, New York, has been a key player in the region's water resource management since its completion in 1912. Owned privately, Denley is regulated by the NYS DEC and the Federal Energy Regulatory Commission, ensuring that it meets state and federal standards for safety and operation. With a dam height of 29 feet and a length of 350 feet, Denley has a storage capacity of 350 acre-feet and covers a surface area of 41 acres.
Situated on the Black River in Lewis County, Denley plays a crucial role in both flood control and electricity generation for the surrounding area. The dam's spillway, with a width of 284 feet, helps manage the flow of water during peak discharge events. Despite its age, Denley has a low hazard potential and a moderate risk assessment rating, indicating that it is well-maintained and poses minimal risk to the community. Emergency preparedness measures, including an Emergency Action Plan last revised in December 2020, ensure that any potential risks are effectively managed.
Overall, Denley stands as a testament to the enduring importance of hydroelectric infrastructure in the face of climate change and evolving water resource management practices. As a historic and functional piece of the region's hydrology, Denley continues to serve as a reliable source of renewable energy and a critical component of the local water management system. Its role in balancing environmental concerns with energy production highlights the complex interplay between water resources and climate resilience in the modern era.
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 Denley -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Black River Near Boonville Ny | 399 cfs | → |
| Independence River At Donnattsburg Ny | 84 cfs | → |
| Mohawk River Below Delta Dam Near Rome Ny | 226 cfs | → |
| West Canada Creek Near Wilmurt Ny | 292 cfs | → |
| East Branch Fish Creek At Taberg Ny | 499 cfs | → |
| Beaver River At Croghan Ny | 564 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Denley .
Boat launches
- Black River
- Delta Lake State Park Town Of Western
- Soft Maple Reservoir
- Stillwater Reservoir
- Twichell Lake
Campgrounds
- Pixley Falls State Park
- Whetstone Gulf State Park
- Delta Lake State Park
- Nicks Lake - Dec
- Limekiln Lake - Dec
Track Denley 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 Denley
Where does the data for Denley 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 Denley .