Lake Jb Thomas Dam
Lake Jb Thomas Dam is an earth dam located in Scurry County, Texas, built in 1952. It carries a High hazard potential classification and has a fair condition assessment.
About Lake Jb Thomas Dam
The primary purpose of Lake Jb Thomas Dam is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Colorado River Municipal Water District (local government). It impounds the Colorado River near Colorado City.
The dam stands 105 feet tall and stretches 9,200 feet across, creates a reservoir covering 7,820 acres, has a maximum storage capacity of 430,600 acre-feet, and collects water from a drainage area of 997 square miles. Completed in 1952, 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 01/10/2024.
At 105 feet, this dam is taller than 98% of all dams in the United States.
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 Texas 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 | Texas |
| County | Scurry |
| Nearest City | Colorado City |
| River/Stream | Colorado River |
| Coordinates | 32.58333, -101.13500 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 105 ft |
| Dam Height | 105 ft |
| Dam Length | 9,200 ft |
| Year Completed | 1952 (74 years old) |
Storage & Hydraulics
| NID Storage | 430,600 acre-ft |
| Max Storage | 430,600 acre-ft |
| Normal Storage | 200,604 acre-ft |
| Surface Area | 7,820 acres |
| Drainage Area | 997 sq mi |
| Max Discharge | 161,002 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | COLORADO RIVER MUNICIPAL WATER DISTRICT |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 01/10/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX04138 |
| Federal ID | TX04138 |
| More Info | State Dam Safety Program |