L & N Reservoir Reservoir Report
Last Updated: December 6, 2025
L & N Reservoir, located in Mount Vernon, Illinois, is a crucial water supply resource owned by the local government and regulated by the Illinois Department of Natural Resources.
°F
°F
mph
Wind
%
Humidity
Summary
Built in 1910, this Earth dam stands at a height of 25 feet and spans 720 feet in length, with a storage capacity of 353 acre-feet. The reservoir primarily serves the purpose of water supply, drawing water from the TRIB Casey Fork river.
Despite its age, L & N Reservoir remains a vital infrastructure with a high hazard potential, prompting regular inspections and maintenance. The spillway, with a width of 113 feet, is uncontrolled, and the outlet gates operate in a similar manner. The reservoir holds a moderate risk rating of 3, highlighting the need for ongoing risk management measures to ensure the safety and security of the surrounding community.
In the event of an emergency, contact information and guidelines for Emergency Action Plans (EAP) are not readily available, indicating a potential area for improvement. With its historical significance and continued importance as a water supply source, L & N Reservoir serves as a valuable asset for the region, requiring careful monitoring and management to mitigate risks and safeguard its operation for the future.
Year Completed |
1910 |
Dam Length |
720 |
Dam Height |
25 |
River Or Stream |
TRIB CASEY FORK |
Primary Dam Type |
Earth |
Nid Storage |
353 |
Outlet Gates |
Uncontrolled |
Hazard Potential |
High |
Foundations |
Unlisted/Unknown |
Nid Height |
25 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
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.
L & N Reservoir