Big Horn Dike B
Big Horn Dike B is an earth dam located in Johnson County, Wyoming, built in 1964. It carries a High hazard potential classification and has a fair condition assessment.
About Big Horn Dike B
The primary purpose of Big Horn Dike B is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Big Horn Reservoir Company -dave Masters (private). It impounds the Cross Creek near Beckton.
The dam stands 50 feet tall, creates a reservoir covering 179 acres, has a maximum storage capacity of 5,705 acre-feet, and collects water from a drainage area of 10 square miles. Completed in 1964, the structure is well into its service life at over 50 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 08/08/2023.
At 50 feet, this dam is taller than 93% 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 Wyoming 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 | Wyoming |
| County | Johnson |
| Nearest City | Beckton |
| River/Stream | Cross Creek |
| Coordinates | 44.53570, -107.20260 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 50 ft |
| Dam Height | 50 ft |
| Year Completed | 1964 (62 years old) |
Storage & Hydraulics
| NID Storage | 5,705 acre-ft |
| Max Storage | 5,705 acre-ft |
| Normal Storage | 4,624 acre-ft |
| Surface Area | 179 acres |
| Drainage Area | 10 sq mi |
| Max Discharge | 1,300 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | BIG HORN RESERVOIR COMPANY -DAVE MASTERS |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 08/08/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WY01867 |
| Federal ID | WY01867 |
| More Info | State Dam Safety Program |