Heron Dam dam
Heron Dam
Heron Dam, located in Grand Blanc, Michigan, is a state-owned structure primarily used for recreation along Thread Creek. Completed in 1969, this earth dam stands at a height of 26 feet with a hydraulic height of 23.1 feet and a length of 1025 feet. The dam has a normal storage capacity of 1100 acre-feet and a maximum storage of 1600 acre-feet, providing essential water resources for the area.
With a high hazard potential and fair condition assessment as of October 2018, Heron Dam is regularly inspected by Michigan DEGLE to ensure its safety and compliance with state regulations. The dam's spillway type is uncontrolled, with a width of 3 feet, and the structure poses moderate risk according to the latest risk assessment. Despite its age, Heron Dam continues to serve as a vital recreational spot and water resource in Oakland County, Michigan, attracting visitors from far and wide to enjoy its scenic beauty.
As climate enthusiasts, it is crucial to monitor and support sustainable management practices for dams like Heron Dam to mitigate potential risks and ensure the preservation of water resources for future generations. By staying informed about the dam's condition, regulatory oversight, and emergency preparedness measures, we can contribute to the safeguarding of this essential infrastructure and the surrounding ecosystem in the face of changing environmental conditions.
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 Heron Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Kearsley Creek Near Davison | 52 cfs | → |
| Huron River At Milford | 73 cfs | → |
| Farmers Creek Near Lapeer | 27 cfs | → |
| Clinton River At Auburn Hills | 184 cfs | → |
| Flint River Near Flint | 614 cfs | → |
| Flint River Near Otisville | 320 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Heron Dam.
Boat launches
- Valley Lake, (Holly Recreation Area), Oakland County
- Groveland Boulevard Oakland County
- Crotched Lake, (Holly Recreation Area), Oakland County
- Thomas Road Oakland County
- Hillsboro Road Oakland County
- Sawmill Lake Road Hadley Township
Campgrounds
- Holly State Rec Area
- Group Camping Area 14
- Groveland Oaks County Park
- Group Camping Area 12
- Group Camping Area 11
- Group Camping Area 10
Fishing spots
Track Heron 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 Heron Dam
Where does the data for Heron 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 Heron Dam.