Middle Cooperstown Reservoir Report

Last Updated: December 5, 2025

Middle Cooperstown is a privately-owned earth dam located in Cooperstown, California, along the Tr Dry Creek.


°F

°F

mph

Wind

%

Humidity

Summary

Built in 1947, this dam stands at a height of 24 feet and has a storage capacity of 90 acre-feet, primarily serving the purpose of water supply. Despite its low hazard potential and satisfactory condition assessment, Middle Cooperstown is regulated and inspected by the California Department of Water Resources for safety compliance.

Situated in Tuolumne County, Middle Cooperstown plays a crucial role in water resource management in the region, providing water supply for various uses. The dam's location in the San Francisco District and its proximity to the city of Cooperstown make it a significant infrastructure for maintaining water quality and quantity in the area. With a surface area of 17 acres and a hydraulic height of 19.9 feet, Middle Cooperstown contributes to maintaining the ecological balance of the surrounding area.

Water resource and climate enthusiasts would be intrigued by the operational and regulatory details of Middle Cooperstown, including its last inspection date in November 2019 and its compliance with state regulations for dam safety. The dam's association with the San Francisco District, along with its role in water supply management, highlights its importance in ensuring sustainable water resources for the community. Middle Cooperstown stands as a testament to responsible water infrastructure development and management in California's dynamic climate conditions.

Year Completed

1947

Dam Length

550

Dam Height

24

River Or Stream

Tr Dry Creek

Primary Dam Type

Earth

Surface Area

17

Hydraulic Height

19.9

Nid Storage

90

Hazard Potential

Low

Nid Height

24
       
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.