Crazy Sombreo Reservoir Report

Last Updated: December 5, 2025

Crazy Sombreo is a privately owned irrigation dam located in Meagher, Montana, along Spring Creek.


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Summary

Built in 1950 by the USDA NRCS, this Earth type dam stands at 58 feet tall with a hydraulic height of 53 feet and a length of 340 feet. It serves the primary purpose of irrigation, providing a storage capacity of 205 acre-feet and a normal storage of 163 acre-feet. With a surface area of 7.7 acres and a drainage area of 1.5 square miles, the dam has a significant hazard potential and moderate risk assessment.

Managed by the DNRC, Crazy Sombreo has state jurisdiction and regulation, with permitting, inspection, and enforcement in place. The dam features an uncontrolled spillway with a width of 15 feet and is situated in Congressional District 00 of Montana, represented by Greg Gianforte. While the condition assessment is not rated and there are no recent inspection dates available, the dam is considered to have moderate risk management measures in place. With its unique design and historical significance, Crazy Sombreo remains a key feature in the water resource infrastructure of the area, attracting enthusiasts interested in water resource management and climate adaptation.

Year Completed

1950

Dam Length

340

Dam Height

58

River Or Stream

Spring Creek

Primary Dam Type

Earth

Surface Area

7.7

Hydraulic Height

53

Drainage Area

1.5

Nid Storage

205

Hazard Potential

Significant

Nid Height

58
       
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.