Pierce Lake Dam dam
Pierce Lake Dam
Pierce Lake Dam, located in Winnebago, Illinois, is a state-regulated earth dam designed by Robert H. Anderson and completed in 1960. The dam's primary purpose is for recreation, with a maximum storage capacity of 4,785 acre-feet and a normal storage capacity of 2,660 acre-feet. The dam stands at a height of 46 feet and spans 470 feet along Willow Creek, a tributary of the Rock River.
With a hazard potential rated as high and a moderate risk assessment, Pierce Lake Dam is a significant water resource structure in the area. The spillway, with a width of 190 feet, is uncontrolled, and the dam's outlet gates are also uncontrolled. The dam's inspection frequency is once a year, with the last inspection conducted in July 2020. While the condition assessment is listed as not available, the dam has a history of state regulation, permitting, inspection, and enforcement to ensure its safety and compliance with regulations.
For water resource and climate enthusiasts, Pierce Lake Dam offers a fascinating insight into the management and regulation of a recreational earth dam in Illinois. With its impressive storage capacity, location on Willow Creek, and history of state oversight, the dam serves as a vital part of the local water infrastructure. The high hazard potential and moderate risk assessment highlight the importance of ongoing monitoring and maintenance to ensure the safety of the dam and surrounding areas.
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 Pierce Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Rock River At Rockton | 5,610 cfs | → |
| Kishwaukee River At Belvidere | 258 cfs | → |
| Kishwaukee River Near Perryville | 625 cfs | → |
| Pecatonica River Nr Shirland | 1,650 cfs | → |
| South Branch Kishwaukee River Nr Fairdale Il | 98 cfs | → |
| Rock River At Afton | 3,240 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Pierce Lake Dam.
Boat launches
- Harlem Road Winnebago County
- Lakecrest Road Winnebago County
- Draft Machesney Park
- Rock River Recreation Path Rockford
- Cherry Valley Path Cherry Valley
- Freeport Road Rockton
Campgrounds
- Hononegah Forest Preserve Campground
- Rivers Edge Campground
- Sugar River Forest Preserve - Pine Tree
- Sugar River Forest Preserve - Riverfront
- Camp Lakota - A Boyscouts Of America Camp
- Orpr Camp
Fishing spots
Track Pierce 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 Pierce Lake Dam
Where does the data for Pierce 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 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 Pierce Lake Dam.