Union Gas dam
Union Gas
Union Gas, also known as Messalonskee No.5 Dam, is a private hydroelectric facility located in Sidney, Maine. Constructed in 1924, this masonry dam stands at a height of 27.6 feet and spans 343 feet in length, with a storage capacity of 600 acre-feet and a maximum discharge rate of 2460 cubic feet per second. The dam serves multiple purposes, including hydroelectric power generation and recreation, and is regulated by the Federal Energy Regulatory Commission.
Situated on the Messalonskee Stream within the Kennebec County, Union Gas plays a vital role in water resource management and climate resilience in the region. Despite its low hazard potential, the dam is subject to regular inspections and emergency preparedness measures to ensure its safe operation. With a very high risk assessment rating, stakeholders are actively involved in risk management strategies to mitigate potential threats and safeguard the surrounding community and environment.
As a significant infrastructure for water resource management and renewable energy production, Union Gas highlights the importance of maintaining and monitoring dams for sustainable development. With its historical significance and modern-day contribution to the local economy, this hydroelectric facility serves as a model for balancing environmental conservation with energy needs. Moving forward, continued collaboration between stakeholders and regulatory agencies will be essential in ensuring the long-term resilience and effectiveness of Union Gas in a changing climate.
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 Union Gas -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Kennebec River At North Sidney | 10,100 cfs | → |
| Sandy River Near Mercer | 1,130 cfs | → |
| Sheepscot River At North Whitefield | 329 cfs | → |
| Cobbosseecontee Stream At Gardiner | 756 cfs | → |
| Carrabassett River Near North Anson | 739 cfs | → |
| Ducktrap River Near Lincolnville | 28 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Union Gas .
Track Union Gas 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 Union Gas
Where does the data for Union Gas 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 Union Gas .