Black Mountain Detention Basin Dam
Black Mountain Detention Basin Dam is an earth dam located in Clark County, Nevada, built in 2000. It carries a High hazard potential classification and has a fair condition assessment.
About Black Mountain Detention Basin Dam
The primary purpose of Black Mountain Detention Basin Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by City Of Henderson (local government). It impounds the Las Vegas Wash-tr near Henderson.
The dam stands 40 feet tall and stretches 1,262 feet across, creates a reservoir covering 20 acres, has a maximum storage capacity of 394 acre-feet, and collects water from a drainage area of 3 square miles. Completed in 2000, the structure is 26 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 02/27/2024.
At 40 feet, this dam is taller than 87% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Nevada dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Nevada |
| County | Clark |
| Nearest City | Henderson |
| River/Stream | Las Vegas Wash-tr |
| Coordinates | 35.98724, -114.99477 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 40 ft |
| Dam Height | 40 ft |
| Dam Length | 1,262 ft |
| Year Completed | 2000 (26 years old) |
Storage & Hydraulics
| NID Storage | 394 acre-ft |
| Max Storage | 394 acre-ft |
| Surface Area | 20 acres |
| Drainage Area | 3 sq mi |
| Max Discharge | 21,900 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | CITY OF HENDERSON |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 02/27/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | NV10550 |
| Federal ID | NV10550 |
| More Info | State Dam Safety Program |