Strong Arm No 1 (upper) is a dam located in Franklin County, Idaho, built in 1887. It carries a High hazard potential classification and has a fair condition assessment.
Dam profile
NID height · 39 ft39 ft tall and 480 ft long, taller than 85% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Strong Arm No 1 (upper)
Strong Arm No 1 (upper) is a dam in Franklin, Idaho. The dam is private-owned. It impounds the Battle Creek Bear River near Warm Springs.
The dam stands 39 feet tall and stretches 480 feet across, creates a reservoir covering 131 acres, has a storage capacity of 1,713 acre-feet, and collects water from a drainage area of 29 square miles. Completed in 1887, the structure is over a century 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 04/04/2018. That was 8 years ago, which is on the longer end for a high-hazard structure.
At 39 feet, this dam is taller than 85% 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 Idaho 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 | Idaho |
| County | Franklin |
| Nearest City | Warm Springs |
| River/Stream | Battle Creek Bear River |
| Coordinates | 42.23330, -111.86170 |
Physical Characteristics
| NID Height | 39 ft |
| Dam Height | 39 ft |
| Dam Length | 480 ft |
| Year Completed | 1887 (139 years old) |
Storage & Hydraulics
| NID Storage | 1,713 acre-ft |
| Normal Storage | 1,713 acre-ft |
| Surface Area | 131 acres |
| Drainage Area | 29 sq mi |
| Max Discharge | 360 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Other |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 04/04/2018 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | ID00228 |
| Federal ID | ID00228 |
| More Info | State Dam Safety Program |