CLEWISTON—South Florida’s rainy season has been especially relentless this year, causing Lake Okeechobee’s water levels to rise to alarming levels. The lake now stands at 15.78 feet as of July 30, and continues to rise, with rainfall occurring almost daily.
High lake levels have serious consequences, especially during the height of hurricane season. Is it the responsibility of the Army Corps of Engineers to keep an eye on water levels and to take action when the lake reaches critical levels. John Campbell, public affairs specialist for the Army Corps of Engineers’ Jacksonville Division, which oversees Lake Okeechobee, explained that the Corps has been releasing water from Lake Okeechobee into the Caloosahatchee River to the west and the St. Lucie Canal to the east.
“As we’ve gotten deeper and the lake has continued to rise, we’ve increased the water we’ve been releasing and we’re now discharging at maximum capacity, which varies due to several factors,” said Campbell. Those factors include tidal influences and how much water is already in the Caloosahatchee River and the St. Lucie Canal. “We’re attempting to push out all that we can, but the lake continues to rise because of inflows from the north, mainly, the Kissimmee River Basin, as well as Fisheating Creek.”
This season’s heavy rainfall is not helping the Corps’ efforts. From January 2 to July 30, the district-wide rainfall -- which includes 16 counties stretching south to north from eastern Miami-Dade to southern Orange and east to west from Broward, Palm Beach and Martin to Lee, Collier and northern Monroe -- was 35.05 inches, 6.5 inches higher than average, according to the South Florida Water Management District (SFWMD).
“Our biggest concern is the Herbert Hoover Dike,” explained Campbell. The dike was built by the federal government in the 1930s, after two hurricanes caused earlier embankments to collapse, killing more than 2,500 people in 1926 and 1928. Originally, the dike consisted of 67.8 miles of levee along the south shore of the lake and 15.7 miles along the north shore. After a major hurricane in 1947, additional construction was necessary and in the 1960s, 143 miles of levee, as well as 19 culverts, hurricane gates and other water control structures, were built and named the Herbert Hoover Dike.
The integrity of the dike, however, has been compromised.
“Because of construction methods used in the 1940s and 50s, there has been erosion. As the lake rises, our concern becomes the stability of the dike,” explained Campbell. When the lake reaches levels in the 16 to 17 feet range, the water puts excess pressure on the already compromised dike.
In 2007, an adjusted water control plan was passed and implemented in 2008. The new plan, called 2008LORS, attempts to maintain lower lake levels in order to preserve the Herbert Hoover Dike, according to SFWMD. Previous water control plans, which allowed water levels to reach into the 17 to 18 feet range before it was necessary to take action, caused erosion of the dike, including internal seepage. The current plan lowered the level at which action should be taken to 15.5 feet. The lake has now surpassed that level, and the Corps is doing everything in its power to reduce the water to a lower level.
“The rising lake adds to rising concerns. We will start taking a lot of proactive action. We’ve started doing weekly inspections of the dike, especially in certain areas that were known to have problems in past. If the lake reaches a level above 16.5 feet, we will do inspections on a daily basis. That’s a proactive measure, to detect issues before they become major issues,” said Campbell.
High lake levels not only affect the integrity of the dike, but pose an increased risk for residents who live nearby during hurricane season.
“As a hurricane comes within striking distance, there’s so much water in the lake it’s like a small ocean, and the winds can generate a pretty powerful storm surge, which could impact residents who live along the lake’s edge,” said Campbell. “When [Tropical Storm] Isaac hit in 2012, we received heavy precipitation which amounted to a three-foot increase in a one-month time period. Last year at this time, the lake was between 12 and 12.5 feet. Isaac hit in August. By early October, the lake was 15.93 feet, where it topped out. We haven’t hit that point yet, but we’re well on our way. Clearly, we’re much earlier into the wet season. If we were to see a tropical event that causes a three-foot rise, the lake would be above 18.5 feet. That’s cause for concern. We’re doing our best to stabilize the rise in the lake ... but Mother Nature has a role in that, too.”
Campbell explained that managing the lake levels is a balancing act. As water is released from Lake Okeechobee into the Caloosahatchee River and the St. Lucie Canal, coastal areas are adversely impacted.
“It’s very challenging. The thing we have to balance is the impact to coastal areas when we release water from Lake Okeechobee,” said Campbell.
As of July 30, inflows into the lake totaled 16,215 cubic feet per second, with outflows totaling only 9,473 cubic feet per second. Campbell explained that if rainfall continues at its current rate, the lake will continue to see inflows that exceed outflows.
“The Corps’ highest priority is public safety and actions are being taken to stabilize the dike. The Corps is working on a number of projects to reduce the risk of dike failure, but they will take several years to complete. We started working on some in 2007 and there’s enough work on the dike to take us past 2020. These are long-term fixes,” explained Campbell.
Not only is the current level of Lake Okeechobee causing concern over the stability of the dike and the risk it poses should a hurricane hit, the levels have also caused SFWMD to close the Clewiston locks (S-310) from 9 p.m. until 5:30 a.m., with a lock operator controlling the lock during daytime hours.
Gary Ritter, intergovernmental and outreach representative for SFWMD, explained that when water levels reach the “trigger point” of 15.5 feet, the locks are put into “operational status,” because the high water level poses a flood control problem.
“The locks are in operation from 5:30 in the morning until nine o’clock at night. Otherwise, the lock is in operation and boaters just have to ‘lock in and out’ during the daytime,” explained Ritter.
Boaters who don’t make it to the Clewiston locks by 9 p.m. will have to remain on the lake until the lock reopens in the morning. Ritter is confident in the local boaters, however, and believes they aware of the new schedule so stranded boaters should not be a problem.
“Most boaters are familiar enough now with the lock schedule. We sent out enough press releases,” said Ritter, adding that several other locks on the lake close at night during the summertime in any event, including locks on the north shore of Lake Okeechobee.
Whether it’s the new lock schedule or the threat of a failure in the dike, the rising water level of Lake Okeechobee affects all south Florida residents.
“It’s a very complex issue,” said Campbell. “But the biggest reason behind our efforts is public safety.”