Coastal Water Authority officials are looking to make repairs to the Lake Houston Dam's existing dam structure prior to beginning work on the planned $224 million Lake Houston Dam Spillway Improvement Project.
The overview
CWA Chief Engineer Greg Olinger said the repairs to the dam are unrelated to the spillway improvement project, noting the repairs are required to be implemented for safety reasons.
The repair work, which will total roughly $10 million, will consist of filling voids beneath the dam structure, repairing areas where the concrete has degraded and adding additional groundwater drainage features downstream of the dam.
CWA Board Director Dan Huberty said the repairs to the existing structure—which the agency has dubbed the Lake Houston Dam Void and Concrete Repair Project—were deemed “vital” after an inspection conducted in the second quarter of this year.
“Regular inspections and prompt repairs are vital for maintaining dam stability and longevity, which is why these repairs are being implemented immediately,” Huberty said.
While Huberty said CWA officials are still in the process of preparing a design for the void and concrete repair project, Olinger said design work on the dam spillway improvement project is continuing and construction is expected to begin in summer 2028.
The spillway improvement project was initially proposed after Hurricane Harvey brought to Harris County more than 47 inches of rain over the course of four days in August 2017, according to previous reporting.
Additionally, Huberty said CWA is partnering with the city of Houston to conduct a study that aims to evaluate alternatives to replace or implement a major rehabilitation project for the dam as it is nearing the end of its service life.
About the projects
The Lake Houston Dam Void and Concrete Repair Project will consist of filling voids in the concrete below and around the dam structure and repairing areas where the concrete has degraded.
- Cost: $10 million
- Timeline: second quarter of 2025-2027
- Funding source: Federal Emergency Management Agency Legislative Pre-Disaster Mitigation Grant
- Cost: $224 million
- Timeline: summer 2028-winter 2030
- Funding sources: Hazard Mitigation Grant Program, Texas Legislature, city of Houston, Harris County
The current dam structure, which was built in 1953, consists of a spillway with four small gates that are made to release water at a rate of 10,000 cubic feet per second, according to Houston Public Works’ website.
Huberty noted the analysis with the city of Houston will not affect the design of the spillway improvement project, which will add 11 gates to the existing dam structure, increasing the dam’s discharge capacity to 79,000 cfs upon completion.
“Instead, [the analysis] looks at what would come after that project, so we have a long-term roadmap,” Huberty said.
Olinger said the preliminary design on the spillway improvement project was completed in August, noting CWA officials are aiming to complete the final design for the project by the end of 2026.
Olinger noted the spillway improvement project is expected to wrap up around winter 2030.
Huberty said the trio of projects is being funded by a variety of federal, state and local sources.
Kim Fazzino, real estate agent with Imperato Fazzino Group, said she expects the planned improvements to the Lake Houston Dam to have a positive effect on property values in the area.
Following Hurricane Harvey in 2017, Fazzino said most homes that were affected by flooding actually gained value.
“The homes that flooded got completely redone,” Fazzino said. “Many of those homes needed a face-lift [prior to the flood].”
Fazzino said she expects the improvements to the dam to increase consumer confidence when purchasing homes in flood-prone areas.
Fazzino also noted floods in Kingwood and around Lake Houston haven’t affected flood insurance rates for most homes in the area because they aren’t located in designated flood plains.
“Flood insurance is based on whether you’re in the flood plain,” she said. “The majority of our homes that flooded were not in the flood plain, because we got flooded by [water from] Conroe.”
Looking ahead
In August, Harris County commissioners authorized the issuance of a letter asking FEMA to prioritize and update flood plain maps. Updated maps were last expected in 2023, according to previous reporting, but they have been continually delayed.
Fazzino said updated maps could result in new flood insurance requirements, but she said it would be difficult to discern who would be affected until the new maps are approved.
Concerning the dam spillway improvement project, Fred Flickinger, Houston City Council District E council member, said he was confident in the updated timeline.
Huberty echoed Flickinger’s sentiment.
“From start to finish, considering the size and scope, the project is moving as fast as humanly possible,” Huberty said.
Olinger said officials currently have secured around $143.4 million for the spillway improvement project, leaving a roughly $80.6 million funding gap for the project.
However, Olinger noted $23.4 million set aside through the Federal Emergency Management Agency’s Hazard Mitigation Grant Program is contingent upon meeting certain requirements in the project’s design.
“This assumes the project will achieve a positive benefit-cost ratio during design, which is required to access the FEMA Hazard Mitigation Grant Program Phase 2 funding,” Olinger said. “Without these funds, the gap would be $104 million.”
The timeline
The following are dates of note associated with the Lake Houston Dam Spillway Improvement Project:
- December 2022: The city of Houston directs the Coastal Water Authority to proceed with design of an 11-gate spillway in the eastern embankment of the Lake Houston Dam after determining a previous, fully-analyzed gate concept on the existing spillway carried too much risk to the 72-year-old concrete dam structure.
- December 2025: The city and CWA begin the 30-60-90 design process, with the 30% design portion covering all conceptual sketches involved.
- May 2026: The city and CWA submit the 60% design documents for the project, which will include more detailed plans.
- December 2026: The city and CWA submit final design plans for the project and begin the permitting process.
- Summer 2028: Construction begins on the Lake Houston Dam Spillway Improvement Project.
- Winter 2030: Construction wraps up on the project.
