4 West Reservoir Report
Nearby: Silver Basin 1
Last Updated: March 31, 2026
4 West is a private earth dam located in Morenci, Arizona, with a primary purpose of storing tailings.
Summary
Standing at a height of 226 feet, this dam has a storage capacity of 93,275 acre-feet. It is regulated by the Mine Safety and Health Administration and has a high hazard potential due to its size and location. Despite its critical role in managing water resources in the area, the condition assessment of 4 West is currently listed as "Not Available", highlighting the need for further evaluation and maintenance to ensure its safety and effectiveness.
The dam, owned and operated by a private entity, does not fall under state jurisdiction, permitting, or inspection, emphasizing the importance of federal oversight by the Mine Safety and Health Administration. The dam's location in Graham County, Arizona, under the Los Angeles District, further underscores the need for continuous monitoring and maintenance to prevent any potential hazards or environmental risks. Given its significant storage capacity and high hazard potential, 4 West serves as a crucial infrastructure for water resource management in the region, necessitating regular assessments and adherence to safety guidelines to mitigate any potential risks to the surrounding communities and ecosystems.
As a key structure for tailings storage in the area, 4 West plays a vital role in water resource management and environmental protection. The dam's high hazard potential underscores the importance of regular inspections and maintenance to ensure its structural integrity and safety. With federal oversight from the Mine Safety and Health Administration, it is essential for the private owner to prioritize the condition assessment and risk management of 4 West to safeguard against any potential emergencies or adverse impacts on the local water supply and surrounding environment.
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15-Day Weather Outlook
Dam Length |
1 |
Dam Height |
226 |
Primary Dam Type |
Earth |
Nid Storage |
93275 |
Hazard Potential |
High |
Nid Height |
226 |
Seasonal Comparison
5-Day Hourly Forecast Detail
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.
1 West
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