Mcmillan Dam
Mcmillan Dam is an earth dam located in Lubbock County, Texas, built in 1959. It carries a High hazard potential classification and has a fair condition assessment.
About Mcmillan Dam
The primary purpose of Mcmillan 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 Lubbock County Wcid 1 (local government). It impounds the Double Mountain Fork Brazos R near Ransom Canyon.
The dam stands 76 feet tall and stretches 1,600 feet across, creates a reservoir covering 200 acres, has a maximum storage capacity of 8,280 acre-feet, and collects water from a drainage area of 236 square miles. Completed in 1959, 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 05/18/2022.
At 76 feet, this dam is taller than 97% 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 | Lubbock |
| Nearest City | Ransom Canyon |
| River/Stream | Double Mountain Fork Brazos R |
| Coordinates | 33.53358, -101.69482 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 76 ft |
| Dam Height | 76 ft |
| Dam Length | 1,600 ft |
| Year Completed | 1959 (67 years old) |
Storage & Hydraulics
| NID Storage | 8,280 acre-ft |
| Max Storage | 8,280 acre-ft |
| Normal Storage | 4,200 acre-ft |
| Surface Area | 200 acres |
| Drainage Area | 236 sq mi |
| Max Discharge | 27,520 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | LUBBOCK COUNTY WCID 1 |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 05/18/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX04027 |
| Federal ID | TX04027 |
| More Info | State Dam Safety Program |