Tannery Pond dam
Tannery Pond
Tannery Pond in Winchendon, Massachusetts, is a historic masonry dam completed in 1936 for hydroelectric purposes along the Millers River. With a dam height of 10 feet and a length of 248 feet, it has a storage capacity of 51 acre-feet and a maximum discharge rate of 3000 cubic feet per second. The spillway, controlled with a width of 144 feet, ensures safe water release during high flow events.
Managed by the Federal Energy Regulatory Commission, Tannery Pond has a low hazard potential and a very high risk assessment rating. Despite its age, the dam's condition assessment is not available, and it has not been inspected since August 2017. The emergency action plan was last revised in 2010, and there are no inundation maps or risk management measures in place.
As a significant piece of infrastructure in the region, Tannery Pond serves as a reminder of the intersection between water resources, climate considerations, and the need for proactive risk management to ensure its continued safety and functionality for both energy production and water management in the area.
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 Tannery Pond -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Millers River Near Winchendon | 234 cfs | → |
| Priest Brook Near Winchendon | 51 cfs | → |
| Birch Hill Reservoir At South Royalston | 30 cfs | → |
| Millers River At South Royalston | 39 cfs | → |
| Otter River At Otter River | 102 cfs | → |
| East Branch Tully River Near Athol | 5 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Tannery Pond .
Boat launches
- River Road Royalston
- Laurel Lake Boat Launch
- Pool Pond Boat Launch
- Grassy Pond Boat Launch
- Contoocook Lake Boat Launch
- Doane Hill Road Royalston
Campgrounds
- Lake Dennison State Park
- East Dennison Camping Area
- North Dennison Camping Area
- Otter River State Forest
- Beaman Pond Campground
- Tully Lake
Paddle runs
- First Bridge Upstream On Route 100 To Confluence With West River
- Headwaters To First Bridge Upstream On Route 100
- Headwaters To Confluence With West River (End Of Sherman Road)
- Sewall's Island To Manchester Street Bridge
- Headwaters To North Of Searsburg Reservoir
- Stamford Town Line To Confluence With City Stream
Track Tannery Pond 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 Tannery Pond
Where does the data for Tannery Pond 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 Tannery Pond .