Mattaceunk dam
Mattaceunk
Mattaceunk, also known as Weldon Dam, is a key hydroelectric structure located in Mattawamkeag, Maine, on the picturesque Penobscot River. Built in 1939, this dam stands 45 feet tall and stretches 1170 feet in length, with a storage capacity of 21,000 acre-feet and a surface area of 1700 acres. The dam serves multiple purposes, including flood risk reduction, water supply, navigation, and recreation, showcasing its importance in managing water resources in the region.
Managed by the Federal Energy Regulatory Commission, Mattaceunk has a high hazard potential and a very high risk assessment rating. Despite its age, the dam's condition assessment is currently not available, highlighting the need for regular inspections and maintenance to ensure its safety and efficiency. With a controlled spillway and a maximum discharge capacity of 168,300 cubic feet per second, Mattaceunk plays a crucial role in regulating water flow and supporting the local ecosystem, making it a significant structure for water resource and climate enthusiasts to study and monitor.
With its multi-arch core design and concrete, earth, and gravity dam types, Mattaceunk stands as a testament to engineering ingenuity and the intersection of human infrastructure with natural water systems. As climate change continues to impact water resources, understanding and managing structures like Mattaceunk will be essential in adapting to evolving environmental challenges and ensuring the sustainable use of water for generations to come.
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 Mattaceunk -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Mattawamkeag River Near Mattawamkeag | 3,080 cfs | → |
| East Branch Penobscot River At Grindstone | 2,930 cfs | → |
| Penobscot River At West Enfield | 16,000 cfs | → |
| Piscataquis River At Medford | 2,470 cfs | → |
| Seboeis River Near Shin Pond | 430 cfs | → |
| Grand Lake Stream At Grand Lake Stream | 321 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Mattaceunk .
Boat launches
- Dickey Moore Road 170, Medway
- Medway Road Millinocket
- Aldrich Point Road Lincoln
- Lake Street Lincoln
- Mike Michaud Trail Millinocket
- Folsom Pond Road 500, Lincoln
Campgrounds
- Katahdin Shadows Campground
- Mattawamkeag Wilderness Park
- Remote Site 5k
- Remote Site 5j
- Remote Site 4i
- Remote Sit 3g
Paddle runs
- Hay Brook To Bridge Above Medway At State Route 157
- Ambajejus Falls To The End Of North And South Twin Lakes
- Headwaters To Confluence With West Branch Penobscot River
- Bowlin Camps To Hay Brook
- Headwaters To Confluence With Penobscot River, East Branch
- Headwaters To Mouth At West Branch Pleasant River
More reservoirs
Track Mattaceunk 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 Mattaceunk
Where does the data for Mattaceunk 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 High 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 Mattaceunk .