Lake Murphysboro Dam Reservoir Report

Last Updated: December 6, 2025

Lake Murphysboro Dam, located in Jackson County, Illinois, is a state-regulated earth dam completed in 1947 with a primary purpose of recreation.


°F

°F

mph

Wind

%

Humidity

Summary

The dam, standing at 46 feet tall and stretching 590 feet in length, creates the picturesque Lake Murphysboro, providing a surface area of 166 acres for outdoor enthusiasts to enjoy. With a maximum storage capacity of 4,281 acre-feet and a drainage area of 2.8 square miles, the dam plays a crucial role in managing water resources in the region.

The dam's spillway, with a width of 100 feet, is uncontrolled, and the outlet gates are also uncontrolled. Despite being classified as having a significant hazard potential, the dam is in moderate risk condition. Regular inspections, with a frequency of every three years, help ensure the dam's safety and functionality. The St. Louis District of the US Army Corps of Engineers oversees the dam, working in conjunction with state agencies like the Illinois Department of Natural Resources to regulate, inspect, and enforce dam safety measures. Lake Murphysboro Dam continues to be a vital asset for water resource management and recreational activities in the area.

Year Completed

1947

Dam Length

590

Dam Height

46

River Or Stream

TRIB BIG MUDDY RIVER

Primary Dam Type

Earth

Surface Area

166

Drainage Area

2.8

Nid Storage

4281

Outlet Gates

Uncontrolled

Hazard Potential

Significant

Foundations

Unlisted/Unknown

Nid Height

46
       
Seasonal Comparison

Weather Forecast

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. 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

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, 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.