BUILDING A BETTER DAM
Built in 1953, recent eorts to improve the existing Lake Houston spillway dam have stalled largely due to the dam’s age, although city of Houston ocials believe they have a new path moving forward.
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December 1953: The Lake Houston spillway dam is completed after two years of construction. The dam is designed to release water at a rate of 10,000 cubic feet per second.
August 2017: The dam is overwhelmed with water being discharged at 425,000 cubic feet per second during Hurricane Harvey, leading to ooding around the lake.
1986-87: Ebasco Engineering and Construction Co. designs repair plans for dam, which are completed by LEM Construction over two years .
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While the Federal Emergency Management Agency approved a roughly $47.1 million grant to add gates to the existing dam structure in August 2019, Houston o cials are asking the state for an addi- tional $150 million to fund proposed improvements. Design changes Stephen Costello, chief recovery o cer for the city of Houston, noted several di culties the city has faced with the project, including problems with early designs and securing the additional funding needed to construct a project that will have a meaningful eect on ooding. In December, Houston Mayor Pro Tem Dave Martin announced the city had scrapped a plan that would have added 500 feet of modern oodgates to the existing dam structure. According to Costello, the design would have required a coerdam—an enclosure built within a body of water—to create a dry environment that would allow the work to be carried out safely. “The dam is 70 years old, and [the engineers were] worried that the structural stability of the dam would be compromised by the coerdam,” he said. After determining the design to be unfeasible, Houston o cials announced in December a new design that would entail 11 additional gates being built into the existing embankment on the east side of the current dam structure.
Further, Costello said the new design received a higher benet-to-cost ratio, which he said is determined by assessing the number of properties that would benet from the project as well as social factors, including employees being able to drive to work through streets that are prone to ooding. According to Costello, the additional gates would provide increased ood protection to more than 5,000 structures and provide more than $500 million in economic benets over 50 years. Costello said the new design would also allow the city to prepare for ooding more e ciently. The limitations of the dam currently require o cials to begin releasing water roughly three days in advance of anticipated ooding. It is estimated the water could be released from the lake 10 times faster with the new design. “If we open the [current] gates preemptively and ooding doesn’t occur, we’re subject to state nes for water rights issues, so this will avoid that problem,” Costello said. Securing funding While the FEMA grant approved in 2019 allocated roughly $47 million for the dam improvement project, Costello said the projected cost of the new design will fall between $200 million-$250 million. In addition to the grant, Costello said the HCFCD allocated $20 million for the project in its
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Since Harvey, the city of Houston, Harris County, and state and federal o cials have worked to address the shortcomings of the Lake Houston spillway dam that have been attributed, in part, to ooding around the lake during the hurricane. These eorts include a roughly $200 million design for improvements to the dam released in December that o cials believe will provide a cost-eective solution to the limitations of the current structure. The dam, which was built in 1953, consists of a spillway structure with four small gates that are made to release water at a rate of 10,000 cubic feet per second, Houston o cials said. According to the Harris County Flood Control District, the dam was overwhelmed with water discharged at a rate of 425,000 cubic feet per second during Harvey, which Rehak said contributed to the rapid rising of the San Jacinto River and ooding near his home. Taylor Landin, chief policy o cer for Partnership Lake Houston, stressed the importance of making improvements to the dam structure. “Necessary ood gate improvements [to the Lake Houston dam] would prevent a recurrence of the devastating residential ooding that forced thousands out of their homes in the aftermath of Harvey,” Landin said.
Yes, we're in network. St. Luke’s Health facilities are in-network with Cigna March 1, 2023. Our aliated physicians from Baylor College of Medicine are already back in-network. Patients can start making appointments now for in-network services after March 1.
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