Thunder Hole Dam dam
Thunder Hole Dam
Located in Matherton, Clinton County, Michigan, Thunder Hole Dam, also known as Keith Wright Pond, is a privately owned structure designed by USDA NRCS with a primary purpose of recreation. Completed in 1966, this earth dam stands at 26 feet in height and stretches 270 feet in length, holding a maximum storage capacity of 91 acre-feet. The dam, situated on a tributary to the Maple River, serves as a controlled spillway with a width of 116 feet and a low hazard potential.
Maintained by the Michigan DEGLE, Thunder Hole Dam has a satisfactory condition assessment as of May 2006, with an inspection frequency of 5 years. The dam poses a very high risk according to the Risk Assessment and is under state regulation, permitting, inspection, and enforcement. With a surface area of 8 acres and a drainage area of 0.98 square miles, the dam provides not only recreational opportunities but also important water resource management functions in the region.
Enthusiasts of water resources and climate will find Thunder Hole Dam an intriguing structure with a rich history in the heart of Michigan. Its design by USDA NRCS, state regulation, and recreational purpose make it a unique and significant part of the local landscape. As a low-hazard dam with a controlled spillway and satisfactory condition, Thunder Hole Dam continues to serve its community while also being a focal point for water management efforts in the region.
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 Thunder Hole Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Maple River At Maple Rapids | 219 cfs | → |
| Fish Creek Near Crystal | 30 cfs | → |
| Grand River At Ionia | 2,230 cfs | → |
| Looking Glass River Near Eagle | 201 cfs | → |
| Grand River At Portland | 1,210 cfs | → |
| Grand River At Lansing | 1,020 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Thunder Hole Dam.
Boat launches
- East Bluewater Highway Muir
- South Tabor Street 270, Lyons
- North Shore Drive 427, Crystal
- Ionia Grand River Boat Ramp
- Howe Road Dewitt Charter Township
Campgrounds
- Maple River Campground
- Sleepy Hollow State Park
- Bertha Brock County Park
- Ionia Equestrian-Rustic
- Ionia State Rec Area
- Camp Greenwood
Fishing spots
Track Thunder Hole 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 Thunder Hole Dam
Where does the data for Thunder Hole 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 Low 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 Thunder Hole Dam.