Merkwan Dam Reservoir Report

Last Updated: December 13, 2025

Merkwan Dam, located in Charles Mix, South Dakota, is a privately owned structure that serves as a crucial water resource in the region.


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Summary

Completed in 1981, this Earth dam stands at a height of 35 feet, with a maximum storage capacity of 120 acre-feet and a normal storage of 100 acre-feet. The dam is situated on Tributary Pease Creek, and its primary purpose is to regulate water flow and provide irrigation and flood control for the surrounding area.

Owned and regulated by private entities, Merkwan Dam is inspected, permitted, and enforced by the South Dakota Department of Environment and Natural Resources (DENR). With a low hazard potential and a current condition assessment of 'Not Rated,' the dam plays a vital role in water management and conservation efforts in the state. Despite not being under the jurisdiction of the US Army Corps of Engineers, the dam's strategic location and design make it a key component in the overall water infrastructure of the area.

As an essential structure for water resource management, climate enthusiasts and stakeholders can appreciate the role of Merkwan Dam in maintaining water security and sustainability in South Dakota. With its modest height, maximum storage capacity, and regulatory compliance, the dam stands as a testament to the importance of proper infrastructure in mitigating the impacts of climate change and ensuring a reliable water supply for agricultural and community needs.

Year Completed

1981

Dam Length

250

Dam Height

35

River Or Stream

TRIB.PEASE CREEK

Primary Dam Type

Earth

Hydraulic Height

35

Nid Storage

120

Hazard Potential

Low

Nid Height

35
       
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.