Flat Rock Dam dam
Flat Rock Dam
Flat Rock Dam, also known as Ahles Dam, is a gravity dam located in Flat Rock, Michigan, along the Huron River. Built in 1924 for recreational purposes, this dam stands at 16.5 feet high with a length of 530 feet, providing a storage capacity of 2395 acre-feet. The dam has a spillway width of 492 feet and a maximum discharge of 14560 cubic feet per second, making it a vital structure for water resource management in the area.
Managed by the local government and regulated by the Michigan DEGLE, Flat Rock Dam has a high hazard potential but is currently in fair condition according to the latest assessment in July 2020. With a moderate risk level, the dam undergoes inspections every three years to ensure its safety and functionality. While the dam does not have any associated structures or locks, it remains a key feature in the region for recreational activities and water conservation efforts along the Huron River. Enthusiasts of water resources and climate will find Flat Rock Dam to be an intriguing structure that plays a significant role in the local ecosystem.
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 Flat Rock Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Ecorse River At Dearborn Heights | 2 cfs | → |
| Lower River Rouge At Inkster | 132 cfs | → |
| Lower River Rouge At Dearborn | 62 cfs | → |
| River Raisin Near Monroe | 535 cfs | → |
| Middle River Rouge At Dearborn Heights | 170 cfs | → |
| Middle River Rouge Near Garden City | 39 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Flat Rock Dam.
Boat launches
- South Huron River Drive 4461, Berlin Township
- Strong Boulevard Berlin Township
- Detroit River, Cherry Island, Wayne County
- Detroit River, Elizabeth Park, Wayne County
- Detroit River, Harrison Ave, Wayne County
- Riverview City Boat Launch
Campgrounds
- East Bend Group Camp
- Sterling State Park
- Wayne County Fairgrounds Rv
- Holiday Beach Conservation Area
- Kc Campgrounds
- Group Use Area
Track Flat Rock 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 Flat Rock Dam
Where does the data for Flat Rock 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 Flat Rock Dam.