Sullivan Lake Dam dam
Sullivan Lake Dam
Sullivan Lake Dam, nestled in Fulton County, Illinois, is a privately-owned structure that serves as a vital water resource for the region. Completed in 1965, this earth dam stands at a height of 34 feet and spans 300 feet in length, creating a reservoir with a storage capacity of 75 acre-feet. With its primary purpose being recreation, Sullivan Lake Dam offers a serene setting for outdoor enthusiasts to enjoy activities such as fishing, boating, and wildlife observation.
Managed by the Illinois Department of Natural Resources (IDNR), Sullivan Lake Dam is subject to regular state inspections, permitting, and enforcement to ensure its safety and compliance with regulations. Despite being classified as having a low hazard potential, the dam is rated as having a moderate risk (3) due to its age and condition assessment being unavailable. The spillway type is listed as uncontrolled, with a width of 34 feet, and the outlet gates are also uncontrolled.
Water resource and climate enthusiasts will appreciate the significance of Sullivan Lake Dam in providing a recreational haven while also serving as a critical structure for managing water levels in the region. As an earth dam with a buttress core type, its historical importance and ongoing maintenance efforts make it a valuable asset for the community. With its location near the TRIB GAINES BRANCH river/stream, Sullivan Lake Dam stands as a symbol of sustainable water management practices and the importance of preserving natural resources 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 Sullivan Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| La Moine River At Ripley | 362 cfs | → |
| Spoon River At Seville | 697 cfs | → |
| La Moine River At Colmar | 239 cfs | → |
| Sangamon River Near Oakford | 3,860 cfs | → |
| Spoon River At London Mills | 496 cfs | → |
| Sangamon River At Petersburg | 2,450 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sullivan Lake Dam.
Boat launches
- West Jefferson Street 598, Havana
- Argyle Park Road Mcdonough County
- Gurney Road Cass County
- County Highway 11 Cass County
- Gridley Road Cass County
Track Sullivan Lake 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 Sullivan Lake Dam
Where does the data for Sullivan Lake 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 Sullivan Lake Dam.