Harmon Pond Dam Reservoir Report
Last Updated: December 15, 2025
Harmon Pond Dam, located in Tiskilwa, Illinois, is a private earth dam that was completed in 1974 with a primary purpose of recreation.
°F
°F
mph
Wind
%
Humidity
Summary
Standing at a height of 37 feet and stretching 1126 feet in length, the dam provides a storage capacity of 51 acre-feet. It is situated on the TRIB Rocky Run river and is regulated by the Illinois Department of Natural Resources, with inspections and enforcement measures in place to ensure its safety and compliance with state regulations.
The dam's spillway, with a width of 36 feet, is uncontrolled, and the hazard potential is deemed significant, with a moderate risk assessment rating. While the condition assessment is currently not available, the dam is inspected every three years to monitor its structural integrity. Despite its private ownership, the dam plays a crucial role in providing recreational opportunities in the surrounding area and contributes to the overall water resource management in Bureau County, Illinois.
As an important structure in the Rock Island District, Harmon Pond Dam serves as a focal point for water resource and climate enthusiasts who are interested in the management and conservation of natural aquatic ecosystems. With its scenic location and recreational offerings, the dam represents a balance between human enjoyment and environmental stewardship, highlighting the interconnectedness of water infrastructure and ecological sustainability in the region.
Year Completed |
1974 |
Dam Length |
1126 |
Dam Height |
37 |
River Or Stream |
TRIB ROCKY RUN |
Primary Dam Type |
Earth |
Nid Storage |
51 |
Outlet Gates |
Uncontrolled |
Hazard Potential |
Significant |
Foundations |
Unlisted/Unknown |
Nid Height |
37 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Big Bureau Creek At Princeton
|
8cfs |
East Bureau Creek Near Bureau
|
2cfs |
Illinois River At Henry
|
3470cfs |
Indian Creek Near Wyoming
|
3cfs |
Vermilion River Near Leonore
|
17cfs |
Green River Near Geneseo
|
185cfs |
Dam Data Reference
Condition Assessment
SatisfactoryNo 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. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
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. Investigations and studies are necessary.
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.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams 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, environment 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.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Harmon Pond Dam