Johnston, located in Bradley County, Tennessee, is a private earth dam constructed in 1963 by the USDA NRCS for multiple purposes such as fire protection, stock, small fish ponds, and recreation.
Wind
Humidity
The dam spans 350 feet in length and has a hydraulic height of 20.9 feet, with a maximum storage capacity of 111 acre-feet and a normal storage of 71 acre-feet. The dam is situated on Brymer Creek and serves as a vital resource for the surrounding community.
Despite being classified as having a low hazard potential, Johnston has a moderate risk assessment rating of 3. Although the dam is not currently rated for its condition, it undergoes inspections every five years, with the last assessment conducted in November 2019. The dam does not have an Emergency Action Plan (EAP) in place, and there is limited information available on risk management measures and inundation maps prepared for potential emergencies.
Johnston is an essential water resource structure in the area, providing water storage for various purposes and serving as a recreational spot for the community. While it has a low hazard potential, the moderate risk assessment highlights the importance of regular inspections and potential improvements to ensure the safety and reliability of the dam in the face of changing climate conditions and emergency situations.
Year Completed |
1963 |
Dam Length |
350 |
River Or Stream |
BRYMER CREEK |
Primary Dam Type |
Earth |
Surface Area |
8.3 |
Hydraulic Height |
20.9 |
Drainage Area |
0.1 |
Nid Storage |
111 |
Structural Height |
25.3 |
Outlet Gates |
None |
Hazard Potential |
Low |
Foundations |
Rock, Soil |
Nid Height |
25 |
| Location | Reservations | Toilets |
|---|---|---|
Harrison Bay State Park
|
||
Skull Island - Chickamauga Lake
|
||
Chester Frost Park
|