An elegant engineering solution designed to increase the safety and stability of a critical asset

Lake Houston Dam Rehabilitation

Built in 1954, Lake Houston Dam is the only source of surface drinking water for over two million Houston, Texas residents. Rehabilitation became critical when the Texas Commission on Environmental Quality (TCEQ) identified this high hazard structure had fallen substantially below the sliding factor of safety (SFS) guidelines.

When initial studies recommended a costly solution, Coastal Water Authority (CWA) engaged our water resources engineers for a second opinion. We created a mathematical stability model specific to the dam’s complex geometry, and performed geotechnical analyses for seepage, settlement, and bearing capacity. Verifying our findings through ground investigation, we then created a computational fluid dynamic (CFD) model to evaluate the benefits and risks associated with modifying or demolishing existing elements. Our efficient design solution backs water up against the dam to use its weight as a stabilizer, effectively creating a small dam below a bigger dam. Extremely close coordination was required so construction and temporary works would not put the existing structure at risk.

Despite major flooding event setbacks and the challenges of protecting the dam’s integrity, we completed the rehabilitation on time and within budget. Lake Houston Dam is now one of the only dams in Texas that complies with TCEQ’s SFS requirements.