Grayhorse Detention Dam, located in Duncan, Arizona, was completed in 1956 by the Bureau of Land Management with a primary purpose of flood risk reduction along the Round Mountain Draw tributary.
Wind
Humidity
This gravity dam stands at an impressive 28 feet in structural height and has a hydraulic height of 23 feet, with a length of 603 feet. With a capacity to hold 120 acre-feet of water, the dam serves to protect the surrounding area from potential flood hazards, with a low hazard potential and fair condition assessment.
Despite being owned, funded, designed, and regulated by the Bureau of Land Management, Grayhorse Detention Dam does not fall under state jurisdiction or regulation. This federal-owned structure operates without state permitting, inspection, or enforcement. With a moderate risk assessment rating of 3, the dam has an inspection frequency of 5 years and was last assessed in August 2015. While the dam has not been modified since its completion, it continues to serve as a vital tool in managing flood risks in the Greenlee County area.
Year Completed |
1956 |
Dam Length |
603 |
River Or Stream |
ROUND MOUNTAIN DRAW TRIBUTARY |
Primary Dam Type |
Gravity |
Surface Area |
20 |
Hydraulic Height |
23 |
Nid Storage |
120 |
Structural Height |
28 |
Hazard Potential |
Low |
Foundations |
Unlisted/Unknown |
Nid Height |
28 |
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 |