Riverdale Mills dam
Riverdale Mills
Riverdale Mills, also known as Knott Dam, is a private hydroelectric facility located in Northbridge, Massachusetts along the Blackstone River. Built in 1957, this concrete dam stands at a height of 9.5 feet and has a length of 142 feet, serving multiple purposes including flood risk reduction, hydroelectric power generation, and water supply. With a storage capacity of 89 acre-feet and a maximum discharge of 19,400 cubic feet per second, Riverdale Mills plays a crucial role in managing water resources in the region.
Managed by the Federal Energy Regulatory Commission, Riverdale Mills has a low hazard potential and a very high risk assessment rating. Despite its age, the dam's condition assessment is not currently available, and its emergency action plan has not been updated since 2009. The dam features controlled spillways and outlet gates for efficient water management, serving as an important infrastructure for both environmental and energy needs in the area. For water resource and climate enthusiasts, Riverdale Mills represents a unique blend of history, engineering, and sustainable practices in harnessing the power of water for the benefit of the community.
Overall, Riverdale Mills stands as a testament to the importance of hydroelectric infrastructure in managing water resources and supporting sustainable energy practices. Its location along the Blackstone River in Worcester County, Massachusetts, underscores its significance in the region's water management efforts. With a focus on flood risk reduction, hydroelectric power generation, and water supply, Riverdale Mills exemplifies the intersection of technology, nature, and innovation in meeting the challenges of climate change and water resource sustainability.
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 Riverdale Mills -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Blackstone River At Northbridge | 1,000 cfs | → |
| West River Below West Hill Dam | 1 cfs | → |
| Blackstone River | 113 cfs | → |
| Quinsigamond River At North Grafton | 15 cfs | → |
| Branch River At Forestdale | 60 cfs | → |
| Nipmuc River Near Harrisville | 12 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Riverdale Mills .
Boat launches
- Brigham Hill Road Grafton
- West Main Street 209, Hopkinton
- Torrey Road 22, Sutton
- Wood Street 291-299, Hopkinton
- Oak Island Boat Ramp
- Cedar Street 154-180, Hopkinton
Track Riverdale Mills 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 Riverdale Mills
Where does the data for Riverdale Mills 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 Riverdale Mills .