Mill C dam
Mill C
Mill C, also known as Woods Mill Pool Dam, is a historic structure located in Morrisonville, New York, along the Saranac River. Built in 1922, this masonry dam stands at a height of 43 feet and has a storage capacity of 40.3 acre-feet, making it primarily used for hydroelectric power generation and water supply purposes. The dam is regulated by the Federal Energy Regulatory Commission and undergoes regular inspections to ensure its safety and functionality.
With a significant hazard potential and a moderate risk assessment rating, Mill C plays a crucial role in managing water resources and supporting the local community's energy needs. Despite its age, the dam continues to operate efficiently, with three slide (sluice gate) outlets and an uncontrolled spillway design. The dam's association with the Federal Energy Regulatory Commission ensures that it meets rigorous safety standards and is maintained to mitigate any potential risks associated with its operation. For water resource and climate enthusiasts, Mill C is a fascinating example of early 20th-century engineering that continues to play a vital role in modern water management practices.
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 Mill C -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Salmon River At South Plattsburgh Ny | 44 cfs | → |
| Saranac River At Plattsburgh Ny | 1,170 cfs | → |
| Little Ausable River Near Valcour Ny | 43 cfs | → |
| Ausable River Near Au Sable Forks Ny | 600 cfs | → |
| Little Chazy River Near Chazy Ny | 64 cfs | → |
| E Br Ausable River At Au Sable Forks Ny | 237 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Mill C .
Boat launches
- Green Street 32, Plattsburgh
- Green Street Plattsburgh
- Peru Boat Launch
- Chazy Lake
- Fish Hatchery Road Grand Isle
- West Shore Road Grand Isle
Campgrounds
- Macomb Reservation State Park
- Cumberland Bay State Park
- Primitive Campsite 13
- Primitive Campsite 14
- Primitive Campsite 16
- Primitive Campsite 15
Track Mill C 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 Mill C
Where does the data for Mill C 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 Significant 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 Mill C .