Countryside Landfill Dam Reservoir Report

Last Updated: December 5, 2025

Countryside Landfill Dam, located in Grayslake, Illinois, is a private-owned structure designed by GEOSYNTECH to reduce flood risk in the area.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1997, this earth-type dam stands at a height of 13 feet and stretches 960 feet in length. It serves the primary purpose of flood risk reduction, with a storage capacity of 66 acre-feet and a maximum discharge capacity.

The dam is situated along the Avon-Fremont Drainage Ditch and is regulated by the Illinois Department of Natural Resources. With a low hazard potential and moderate risk assessment, the dam has an uncontrolled spillway with a width of 20 feet. Although the condition assessment is not available, the dam undergoes inspections every five years to ensure its structural integrity and safety.

While the Countryside Landfill Dam lacks certain emergency preparedness measures such as an Emergency Action Plan and updated contact information, it plays a crucial role in mitigating flooding in the region. Its strategic location and design make it a significant asset in managing water resources and climate resilience in Lake County, Illinois.

Year Completed

1997

Dam Length

960

Dam Height

13

River Or Stream

AVON-FREMONT DRAINAGE DITCH

Primary Dam Type

Earth

Surface Area

122

Drainage Area

0.3

Nid Storage

66

Outlet Gates

None

Hazard Potential

Low

Foundations

Soil

Nid Height

13
       
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.