Dam Report

Ripogenus dam

Maine, USA West Branch Penobscot River Hazard High
Today high
--
Tonight low
--
Dam height
83ft
Hazard rating
High
Loading current conditions…
Loading next 24 hours…
Loading 7-day outlook…
Ripogenus                                                         -- None dam
Ripogenus None · West Branch Penobscot River
About this dam

Ripogenus

Ripogenus is a captivating hydroelectric dam located in Millinocket, Maine, along the beautiful West Branch Penobscot River. Constructed in 1916, this concrete, earth, and gravity dam stands at an impressive height of 83 feet and has a length of 795 feet, with a storage capacity of 688,000 acre-feet. The dam serves multiple purposes including flood risk reduction, recreation, and water supply, making it a vital resource for the surrounding area.

Managed by the Federal Energy Regulatory Commission, Ripogenus poses a high hazard potential due to its location and structural features. Despite its age, the dam remains in good condition with regular inspections ensuring its safety and integrity. With a maximum discharge capacity of 95,660 cubic feet per second, Ripogenus plays a crucial role in managing water flow and providing clean energy to the region. For water resource and climate enthusiasts, Ripogenus represents a historic and essential piece of infrastructure that continues to contribute to the sustainable development of the area.

In addition to its engineering marvel, Ripogenus also supports fish and wildlife habitats, highlighting the balance between human needs and environmental conservation. With its controlled spillway and eight slide gates, the dam is equipped to handle emergencies and ensure the safety of downstream areas. As climate change continues to impact water resources, the importance of structures like Ripogenus in managing water flow and mitigating risks becomes increasingly evident, making it a fascinating subject for those interested in water resource management and climate resilience.

StateNone
River / streamWest Branch Penobscot River
NID IDME00204
Owner typeNot Listed
Primary purposeHydroelectric
Year built1916
Dam height83 ft
Dam length795 ft
Max storage688,000 AF
Normal storage688,000 AF
Surface area29,279.0 ac
Drainage area1,422.0 sq mi
Hazard potentialHigh
ConditionNot Available
Last inspectionWed, 30 Sep 2020 00:00:00 GMT

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.
Detailed forecast

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.

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

Loading hourly forecast…
Deep dive

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.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
Loading detailed forecast…
Long-term outlook

15-day temperature & precipitation

Daily temperatures, snow, and rain projected over the next two weeks.

Loading 15-day outlook…
Regional inflow

Nearby streamflow gauges

USGS streamgauges around Ripogenus -- inflows here typically show up in storage 24-72 hours later.

Track Ripogenus 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.

FAQ

About Ripogenus

Where does the data for Ripogenus 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.

More reservoirs

Other water bodies near here

Snoflo-tracked reservoirs and dams within driving distance of Ripogenus .