Harris Dam Reservoir Report
Nearby: Mission Creek Dam Peas Lake Dam
Last Updated: December 5, 2025
Harris Dam, also known as Mount Pleasant Dam, is a private-owned structure located in Isabella, Michigan, along the Chippewa River.
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Summary
Built in 1870, this earth dam stands at 16 feet high and spans 490 feet in length, serving primarily for recreational purposes. With a storage capacity of 150 acre-feet, the dam plays a crucial role in managing water resources in the area, with a maximum discharge capability of 13,500 cubic feet per second.
Despite its age, Harris Dam has a low hazard potential and is currently not rated for its condition assessment. The dam features an uncontrolled spillway with a width of 110 feet, ensuring the safe release of excess water during high flow events. While the risk assessment for the dam is moderate, it lacks updated emergency action plans and inundation maps, indicating a need for further risk management measures to be implemented.
Overall, Harris Dam stands as a historical landmark in the region, providing essential recreational opportunities while also serving as a vital component of water resource management along the Chippewa River. With its moderate risk assessment and low hazard potential, continued monitoring and maintenance efforts will be essential to ensure the long-term safety and functionality of this important infrastructure.
Year Completed |
1870 |
Dam Length |
490 |
Dam Height |
16 |
River Or Stream |
Chippewa River |
Primary Dam Type |
Earth |
Surface Area |
2 |
Hydraulic Height |
16 |
Drainage Area |
391 |
Nid Storage |
150 |
Structural Height |
16 |
Hazard Potential |
Low |
Nid Height |
16 |
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.
Harris Dam