“When will the next phase of cutoff wall begin?”
“How long will the Lake Okeechobee Scenic Trail be impacted?”
“Will the Corps raise water levels in the lake once construction is finished?”
This is just a sampling of questions asked by concerned stakeholders during recent public meetings, as U.S. Army Corps of Engineers, Jacksonville District project managers discussed the next phase of repair work at Herbert Hoover Dike (HHD) – completion of a Dam Safety Modification Study (DSMS).
With a cutoff wall seepage barrier installed between Port Mayaca and Belle Glade, and with work under way to remove or replace 32 water control structures surrounding the lake, the Corps is looking at the DSMS to provide the framework for future projects necessary to reduce the risk of failure of the dike.
“The Dam Safety Modification Study is a comprehensive, system-wide study intended to identify risks in the system, and to recommend the necessary measures that can reduce the risk of failure,” said Tim Willadsen, HHD project manager.
While certain sections of the dike have been studied before, HHD has never undergone a review this comprehensive and detailed. Each segment of the dike will be thoroughly reviewed for its geology and geometry, with particular attention given to scenarios that would cause the dike to fail.
“The study will analyze the information developed and organize it into a report that covers the 143-mile dike as a single system, with alternative plans that include structural and non-structural solutions to reduce existing risk in the system,” said Micah Buchholz, civil engineer. “The selected plans and associated implementation schedule will be the blueprint for future project work.”
As part of the process, Jacksonville District is gathering input from the public and from environmental stakeholders, to ensure potential environmental issues are identified and addressed as necessary, in accordance with the National Environmental Policy Act (NEPA).
“Lake Okeechobee is an incredible environmental resource used by many species,” said Angie Dunn, biologist. “We know there are important habitats, including wetlands, around the lake, as well as many protected species. As work on the HHD progresses, we will have to consider the habitat and species in the area and minimize the impacts.”
Willadsen estimates it will take about two years before the study produces a final report.
“The level of detail necessary to accomplish this study requires a tremendous amount of planning, design and analyses, which will take time to complete,” said Willadsen. “Previous studies focused on specific areas, whereas the Dam Safety Modification Study is comprehensive and includes the entire dike as a system.”
While the study is ongoing, work will continue on replacing water control structures around the lake. Contractors are continuing work at the Culvert 1A site east of Moore Haven, the Culvert 4A site near South Bay, and the Culvert 11 site south of Port Mayaca. Additional contracts are expected to be awarded later this year, and replacement work is expected to continue at various culvert sites through 2018. The Corps will then look to execute the projects identified by the DSMS.
“We will continue replacing water control structures over the next few years while we complete the Dam Safety Modification Study, “ said Willadsen, “If all goes as planned, we will award contracts in 2017 for further risk reduction measures around Lake Okeechobee identified by this study.”
For more information, visit the Dam Safety Modification Study web page: