The U.S. Army Corps of Engineers continues work on Herbert Hoover Dike, the 143-mile structure surrounding Lake Okeechobee. Since 2001, the Corps has made a significant investment, over $870 million, in projects designed to reduce the risk of catastrophic failure of the aging structure.
In the late 1920s, flooding from hurricanes killed thousands of people living in communities around the lake. As a result, Congress authorized the Corps to construct a series of levees. In the 1930s, the Corps built 68 miles of levee on the south shore of the lake, and additional 16 miles of levee near the city of Okeechobee on the north side.
Following another hurricane in 1947 that left much of south Florida under water for weeks, Congress authorized a project that raised and widened the existing levees. Congress also authorized the Corps to build an additional 59 miles of levee, bringing the dike to the 143-mile footprint that it has today. In 1960, the series of levees was renamed the Herbert Hoover Dike.
The dike was built with gravel, rock, limestone, sand and shell. These natural materials allow water to seep through the embankment. As the water level in the lake increases, the seepage can lead to internal erosion. Without intervention, the movement of material within the dike could cause the dike to fail, putting thousands of people in harm’s way.
In the 1990s and early 2000s, the Corps observed performance issues during high water events in Lake Okeechobee. These performance issues included movement of dike material, such as sloughing, the development of sinkholes, and other erosion. The Corps dealt with issues immediately to keep the dike from failing. A series of studies was undertaken on various sections of the dike. As the results of those studies became available, the Corps began rehabilitation of the dike.
Since 2001, the $870 million invested by the Corps has resulted in the following rehabilitation work at the dike:
• Construction of a 21.4 mile seepage barrier (known as a partial-penetrating cutoff wall) between Belle Glade and Port Mayaca on the southeast side of the lake, an area previously identified as Reach 1.
• Replacement of 23 water control structures. These structures (also known as “culverts”) posed a failure risk due to loss of embankment material into and along them. Work on four structures is complete, while 19 others are under contract.
• Removal of one additional water control structure.
• Filling of toe ditch and quarry between Belle Glade and Port Mayaca.
• Vegetation removal along south side of dike
The Corps anticipates completing the following work as dike rehabilitation activities continue.
• Replacement of five water control structures. The Corps anticipates awarding contracts for replacement of five structures along the northwest side of the lake over the next three years.
• Abandonment of three water control structures located near Okeechobee at the north end of the lake.
• Construction of 35 miles of seepage barrier along the south and west sides of the dike. The Corps plans to award a contract in 2017 to resume construction of a partial-penetrating cutoff wall west of Belle Glade. Future work will extend the cutoff wall west through Lake Harbor, Clewiston, Moore Haven and Lakeport.
• Raising the embankment or construction of floodwall at the S-71 and S-72 structures on the Indian Prairie and Harney Pond Canals. This helps reduce the risk of overwashing/overtopping by raising the height of the structure to match the height of the adjacent embankment.
• Armoring the State Route 78 bridge abutments at the Harney Pond Canal. Placement of rock at this location reduces the risk of dike failure due to storm surge brought about by a tropical system with a high lake level.
The Corps estimates the cost of the remaining work will exceed $800 million, bringing the total cost of the rehabilitation effort to more than $1.7 billion. The Corps anticipates rehabilitation work will continue through 2025.
More information at the Herbert Hoover Dike rehabilitation page.