Reynolds Piney Creek Diversion Dam
Reynolds Piney Creek Diversion Dam is an earth dam located in Johnson County, Wyoming, built in 1969. It carries a Significant hazard potential classification.
About Reynolds Piney Creek Diversion Dam
The primary purpose of Reynolds Piney Creek Diversion Dam is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Johnson County Lake Desmet Department (private). It impounds the Piney Creek near Kearny.
The dam stands 22 feet tall and stretches 1,850 feet across, creates a reservoir covering 10 acres, has a maximum storage capacity of 114 acre-feet, and collects water from a drainage area of 12 square miles. Completed in 1969, the structure is well into its service life at over 50 years old.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. The most recent inspection on record was 05/22/2025.
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 | Kearny |
| River/Stream | Piney Creek |
| Coordinates | 44.53080, -106.80960 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 22 ft |
| Dam Height | 22 ft |
| Dam Length | 1,850 ft |
| Year Completed | 1969 (57 years old) |
Storage & Hydraulics
| NID Storage | 114 acre-ft |
| Max Storage | 114 acre-ft |
| Normal Storage | 51 acre-ft |
| Surface Area | 10 acres |
| Drainage Area | 12 sq mi |
| Max Discharge | 4,817 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | JOHNSON COUNTY LAKE DESMET DEPARTMENT |
| Owner Type | Private |
| Hazard Classification | Significant |
| Last Inspection | 05/22/2025 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | WY00461 |
| Federal ID | WY00461 |
| More Info | State Dam Safety Program |