State Line Detention Dam Reservoir Report
Last Updated: December 5, 2025
State Line Detention Dam, located in Greenlee, Arizona, was completed in 1952 by the Bureau of Land Management to serve as a gravity dam primarily for debris control on the Olney Well Draw river or stream.
°F
°F
mph
Wind
%
Humidity
Summary
With a structural height of 27 feet and a hydraulic height of 19 feet, the dam has a storage capacity of 382.6 acre-feet and covers a surface area of 29.7 acres. Despite its low hazard potential, the dam is currently assessed as being in poor condition, indicating a need for maintenance and improvements.
The dam's primary purpose and design as a debris control structure reflect its critical role in managing water resources in the area. However, its poor condition and moderate risk assessment highlight the importance of regular inspections and maintenance to ensure its continued effectiveness and safety. With a history of federal ownership and funding, the Bureau of Land Management remains responsible for the dam's operations, inspections, and regulatory compliance.
Although State Line Detention Dam has not been subject to state jurisdiction or permitting requirements, its location in Franklin, AZ, underscores its significance in water resource management for the region. As climate change continues to impact water availability and extreme weather events, the dam's role in flood control and debris management becomes increasingly vital. Efforts to address the dam's poor condition and mitigate potential risks are essential for safeguarding both the surrounding community and the environment in the face of changing climatic conditions.
Year Completed |
1952 |
Dam Length |
1028 |
River Or Stream |
OLNEY WELL DRAW |
Primary Dam Type |
Gravity |
Surface Area |
29.7 |
Hydraulic Height |
19 |
Drainage Area |
16.3 |
Nid Storage |
382.6 |
Structural Height |
27 |
Hazard Potential |
Low |
Foundations |
Unlisted/Unknown |
Nid Height |
27 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Gila River At Duncan
|
51cfs |
Gila River Below Blue Creek
|
61cfs |
Gila River Near Redrock
|
74cfs |
Gila River Near Clifton
|
65cfs |
Gila River At Head Of Safford Valley
|
93cfs |
San Francisco River At Clifton
|
14cfs |
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.
State Line Detention Dam
Gila