Lake Houston Dam
Lake Houston Dam is a buttress dam located in Harris County, Texas, built in 1954. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Lake Houston Dam
The primary purpose of Lake Houston Dam is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by City Of Houston (local government). It impounds the San Jacinto River near Magnolia Gardens.
The dam stands 66 feet tall and stretches 12,097 feet across, creates a reservoir covering 12,240 acres, has a maximum storage capacity of 281,800 acre-feet, and collects water from a drainage area of 2,828 square miles. Completed in 1954, 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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 07/11/2023.
At 66 feet, this dam is taller than 96% 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 | Harris |
| Nearest City | Magnolia Gardens |
| River/Stream | San Jacinto River |
| Coordinates | 29.91919, -95.13263 |
Physical Characteristics
| Dam Type | Buttress |
| NID Height | 66 ft |
| Dam Height | 66 ft |
| Dam Length | 12,097 ft |
| Year Completed | 1954 (72 years old) |
Storage & Hydraulics
| NID Storage | 281,800 acre-ft |
| Max Storage | 281,800 acre-ft |
| Normal Storage | 146,700 acre-ft |
| Surface Area | 12,240 acres |
| Drainage Area | 2,828 sq mi |
| Max Discharge | 525,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | CITY OF HOUSTON |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 07/11/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX03416 |
| Federal ID | TX03416 |
| More Info | State Dam Safety Program |