Allen Dam dam
Allen Dam
Allen Dam, located in Acton, Massachusetts, is a historic gravity dam built in 1797 on Nashoba Brook. The dam primarily serves for recreational purposes, offering a serene environment for water resource and climate enthusiasts to enjoy. With a height of 14.5 feet and a storage capacity of 154 acre-feet, the dam provides a picturesque setting for outdoor activities such as fishing, boating, and wildlife observation.
Managed by the Department of Conservation and Recreation, the dam is regulated by the state of Massachusetts and undergoes regular inspections to ensure its structural integrity and safety. Despite being classified as having a low hazard potential, the dam is assessed to be in fair condition as of the last inspection in 2009. With a moderate risk level, measures for risk management and emergency preparedness are essential to mitigate any potential issues and maintain the dam's functionality for future generations to enjoy.
Overall, Allen Dam stands as a testament to early American engineering and continues to provide a valuable resource for both recreational and environmental purposes in the Middlesex County area. Its historical significance, coupled with its scenic surroundings and regulated maintenance, make it a noteworthy site for water resource and climate enthusiasts seeking to appreciate the intersection of nature and human infrastructure.
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 Allen Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Nashoba Brook Near Acton | 7 cfs | → |
| Assabet River At Maynard | 95 cfs | → |
| Shawsheen River At Hanscom Field Near Bedford | 7 cfs | → |
| Hobbs Brook At Mill St Nr Lincoln | 0 cfs | → |
| Hobbs Bk Below Cambridge Res Nr Kendall Green | 7 cfs | → |
| Stony Brook At Rt 20 At Waltham | 27 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Allen Dam.
Boat launches
- Seymour Street 1a, Concord
- Emerson Drive Littleton
- South Great Road Lincoln
- Pond Path, Concord
- Harvard Road 314, Stow
- Great Road 687, Littleton
Track Allen 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 Allen Dam
Where does the data for Allen 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 Allen Dam.