Mallison Falls dam
Mallison Falls
Mallison Falls, located in Westbrook, Maine, is a captivating hydroelectric dam on the Presumpscot River with a rich history dating back to its completion in 1900. With a masonry dam type and a height of 14 feet, this structure serves multiple purposes related to hydroelectric power generation. The dam has a storage capacity of 30 acre-feet and a maximum discharge of 5500 cubic feet per second, making it a significant contributor to the local water resource infrastructure.
Despite its age, Mallison Falls continues to play a vital role in the region's energy production and water management systems. The dam's uncontrolled spillway, with a width of 225 feet, adds to its unique features and engineering design. The structure's hazard potential is rated as significant, highlighting the importance of regular inspections and risk management measures to ensure its continued safe operation. Mallison Falls serves as a reminder of the intersection between water resources, climate sustainability, and energy generation 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 Mallison Falls -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Presumpscot River At Westbrook | -999,999 cfs | → |
| Saco River At Cornish | 7,160 cfs | → |
| Mousam River Near West Kennebunk | 225 cfs | → |
| Androscoggin River Near Auburn | 7,760 cfs | → |
| Saco River Near Conway | 1,420 cfs | → |
| Nezinscot River At Turner Center | 43 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Mallison Falls .
Boat launches
- Tow Path Gorham
- Mosher Road Gorham
- Gambo Road Gorham
- Mountain Division Trail Windham
- Snowmobile Falmouth Trail Westbrook
- Sappi Portage Trail Gorham
Track Mallison Falls 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 Mallison Falls
Where does the data for Mallison Falls 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 Mallison Falls .