Manchester Mill Dam dam
Manchester Mill Dam
The Manchester Mill Dam, located in Manchester, Michigan, on the River Raisin, is a gravity dam primarily designed for recreation purposes. Built in 1908, the dam stands at 18 feet high and spans 82 feet in length, with a storage capacity of 210 acre-feet. The dam is regulated by the Michigan Department of Environment, Great Lakes, and Energy (DEGLE) and undergoes regular inspections to ensure its structural integrity.
With a hazard potential rated as high and a condition assessment deemed as fair during its last inspection in 2016, the Manchester Mill Dam poses a risk to the surrounding area in the event of a failure. Despite its age, the dam continues to serve its recreational purpose, offering a surface area of 12 acres for activities such as fishing and boating. The dam's controlled spillway and maximum discharge capacity of 1550 cubic feet per second help manage water flow during periods of high precipitation, reducing the risk of flooding downstream.
As water resource and climate enthusiasts, the Manchester Mill Dam presents an interesting case study in the management and maintenance of aging infrastructure. Its location on the River Raisin, within the Buffalo District of the US Army Corps of Engineers, highlights the importance of proper regulation and inspection protocols to ensure public safety and environmental protection. With its very high risk designation and fair condition assessment, the ongoing monitoring and potential upgrades to the dam are crucial to mitigate any potential hazards and maintain its functionality for future generations to enjoy.
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 Manchester Mill Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| River Raisin Near Manchester | 23 cfs | → |
| Mill Creek Near Dexter | 52 cfs | → |
| Saline River Near Saline | 49 cfs | → |
| River Raisin Near Adrian | 222 cfs | → |
| Huron River At Ann Arbor | 445 cfs | → |
| Malletts Creek At Ann Arbor | 14 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Manchester Mill Dam.
Boat launches
- Bemis Road Bridgewater Township
- Wamplers Lake Road Cambridge Township
- Wamplers Lake Road 1280, Cambridge Township
- Us 12 9697, Cambridge Township
- Cedar Lake Road Sylvan Township
- Loveland Road Sylvan Township
Campgrounds
- W. J. Hayes State Park
- Horsemen's Equestrian Campground
- Burns Cabins
- Sugarloaf Lake - Waterloo State Rec Area
- Green Lake - Waterloo State Rec Area
- Green Lake Rustic Campground
Track Manchester Mill Dam 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 Manchester Mill Dam
Where does the data for Manchester Mill 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 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 Manchester Mill Dam.