Greenwood Reservoir Dam dam
Greenwood Reservoir Dam
Greenwood Reservoir Dam in Gwinn, Michigan, is a privately owned structure that serves as a crucial water supply source in Marquette County. Completed in 1973, this Earth-type dam stands at a height of 60 feet and has a storage capacity of 22,750 acre-feet with a normal storage level of 18,000 acre-feet. Situated on the M Br Escanaba River, the dam plays a vital role in regulating the flow of water and ensuring a stable water supply for the surrounding area.
The dam's spillway, with a controlled design and a width of 280 feet, helps manage potential excess water while maintaining the structural integrity of the reservoir. In terms of safety measures, the dam has been assessed as satisfactory, but it holds a significant hazard potential, leading to a very high risk rating. Regular inspections are conducted, with the last assessment taking place in December 2016. Despite its age, Greenwood Reservoir Dam continues to play a crucial role in water resource management and climate resilience efforts in the region.
As water resource and climate enthusiasts, the Greenwood Reservoir Dam is a fascinating example of the intersection between human infrastructure and natural ecosystems. Its careful design and management by the Michigan DEGLE ensure the sustainable utilization of water resources while mitigating potential risks associated with dam operations. The dam's presence highlights the importance of maintaining critical infrastructure for water supply purposes and underscores the ongoing need for monitoring and assessment to ensure the safety and resilience of our water systems in the face of changing climate conditions.
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 Greenwood Reservoir Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Greenwood Release Near Greenwood | 25 cfs | → |
| Greenwood Diversion Near Greenwood | 17 cfs | → |
| Middle Branch Escanaba River At Humboldt | 20 cfs | → |
| Schweitzer Creek Near Palmer | 6 cfs | → |
| Middle Branch Escanaba River Nr Princeton | 154 cfs | → |
| Michigamme River Near Crystal Falls | 668 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Greenwood Reservoir Dam.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Greenwood Reservoir Dam
Where does the data for Greenwood Reservoir 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 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 below 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.
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.