OKEECHOBEE -- Could changes to the Lake Okeechobee Watershed Restoration Plan (LOWRP) cut costs and expedite the project while preserving most of the water storage capacity? At the Feb. 26 meeting of the County Coalition for the Responsible Management of Lake Okeechobee, St. Lucie and Caloosahatchee Estuaries and the Lake Worth Lagoon, Col. Andrew Kelly, of the U.S. Army Corps of Engineers, said the Corps plans to review how the project could work without the most costly component, the Wetland Attenuation Feature (WAF).
Water storage north of Lake Okeechobee is a key component of the Comprehensive Everglades Restoration Plan (CERP). About 90% of the water (or more) that drains into the lake comes from the north, and due to the canals dug for flood control, it flows much faster than Mother Nature intended. The Lake Okeechobee Watershed Restoration Plan (LOWRP), part of the CERP, was designed to provide some of that storage.
LOWRP plans started in 2000, but the project was put on hold in 2006. Planning started again in 2016. The plan includes three features:
• A wetland attenuation feature (WAF): This shallow 13,000-acre impoundment will hold water up to about 4 feet deep during the wet season. The water would permeate into the earth as the lake level falls; this would not be water storage that would be available for use in the dry season.
• 80 aquifer storage and recovery (ASR) wells with a storage volume of approximately 448,000 acre-feet per year. Water stored in ASR wells can be pumped out and used when needed during dry periods.
• Wetland restoration in two areas on the Kissimmee River — Paradise Run (approximately 3,600 acres) and Kissimmee River Center (approximately 1,200 acres).
Plans also call for public recreation sites in the WAF and wetland restoration sites.
Kelly said they hope to have Congressional approval in time to include LOWRP in the 2022 Water Resources Development Act (WRDA). Congress can pass a WRDA every two years, but has sometimes gone as long as seven years between WRDAs. Congress passed a WRDA for 2020. LOWRP authorization will not take funding away from other authorized CERP projects such as the Everglades Agricultural Area (EAA) reservoir. The corps follows the CERP Integrated Delivery Schedule (IDS) and the EAA reservoir is ahead of LOWRP on the IDS.
Estimated cost: $126,706,000;
no water storage capacity
Restoration of two historic wetlands is the least controversial part of LOWRP. Approximately 1,200 acres of wetlands will be restored at Kissimmee River Center and about 3,500 acres of wetlands at Paradise Run. Both of these wetland areas were drained by the channelization of the Kissimmee River. Project features in wetlands restoration are fairly simple structures, explained to project manager Tim Gysan, in an August 2020 interview with the Lake Okeechobee News. The most difficult part of the wetlands project will be real estate acquisition, he said. For the Kissimmee River Center wetland, approximately 1,048 acres are private lands (89%) and 133 acres (11%) are public lands. For the Paradise Run wetland, approximately 1,485 acres are private lands (41%) and 2,106 acres are public lands (59%).
WAF: Estimated cost $961,460,000;
storage capacity - 46,000 acre feet
Real estate acquisition would also be critical to the WAF. The state already owns about 32% of the land — approximately 4,200 acres. About 68% — approximately 9,000 acres — is in private ownership. In the August 2020 interview, Gysan said it would probably be 20 years or more before the WAF is built due to the complexities in purchasing the real estate. Some landowners have already indicated they will not be willing sellers. Estimated cost of the WAF is $961,460,000.
Unlike other above-ground reservoirs, the WAF would be a dynamic feature with water levels rising and falling. It is not designed to hold water for long periods of time, he explained. The WAF would hold water in the wet season and feed flow to a cluster of ASRs at that site. Water from the WAF would percolate into the earth and evaporate into the air — just as the water in the lake does.
“Historically, the area for the shallow reservoir would have functioned as part of the lake’s littoral zone,” Gysan explained. “We’re not trying to store water over the majority of that site during the dry season.”
USACE Senior Hydrogeologist June Mirecki oversaw the limited geotechnical study on the area. In an August 2020 interview with the Lake Okeechobee News, she said the area planned for the WAF is a former lake bed. “The surficial sediments are permeable sands,” she explained. “As you get deeper and further west, the sand becomes thinner and you get more marine sediments.” The WAF was intended as dynamic storage and as a source for the ASRs, she continued. “It’s not like a standard reservoir that can be accessed whenever you need it.”
Gysan said the corps has conducted some cultural surveys on the state-owned land in the WAF footprint to determine if there are any areas such as Native American burial mounds that must be considered. In public meetings, the Seminole Tribe of Florida has voiced opposition to the WAF, which is close to the border of the Brighton Seminole Reservation.
The WAF component has also drawn opposition from Glades County leaders who do not want to see more land taken off the tax rolls, and from nearby residents in Buckhead Ridge who are concerned about their own safety should the impoundment fail when the WAF is full of water in the wet season.
Before the Herbert Hoover Dike was built, in very wet years the footprint of Lake Okeechobee swelled and flooded about 30% more area than the lake’s current footprint. Part of that occasionally flooded area was privately-owned land. When the Herbert Hoover Dike was built, the corps diked the area that was in public ownership.
ASR wells: Estimated cost $399,259,000;
storage capacity - 448,000 acre feet per year
The third aspect of LOWRP — a plan for 80 ASR wells — is already underway, in a phased, studied approach. In 2019, the Florida Legislature allocated $50 million to the SFWMD to “fast-track” storage north of Lake Okeechobee identified in LOWRP. IN 2020, the Florida Legislature added another $50 million for LOWRP. The ASR wells can be built on property the state already owns adjacent to waterways.
The original Comprehensive Everglades Restoration Plan (CERP), approved by Congress in 2000, included 333 ASR wells to provide water storage, according to Gysan. After the detailed five-year regional modeling effort, the number of wells was reduced.
There is still a possibility more ASR wells will be included in other CERP projects. “It depends on a lot of other project implementation factors,” said Mirecki. In some of the proposed ASR sites, no hydrological data has been gathered. “Eighty is the maximum we think we can do in the LOWRP footprint,” she explained. “That doesn’t eliminate the need for that additional storage.”
At their August 2020 meeting, the SWFMD governing board started the LOWRP ASR project by approving funds for exploratory coring and construction of monitoring wells. At that meeting, SFWMD Director of Ecosystem Restoration and Capital Projects Jennifer Reynolds said ASR wells are considered for use in the Upper Floridan Aquifer or the Middle Floridian Aquifer. To reach those aquifers, the cores will drill down to 1,000 to 2,000 feet deep. She added these are not deep injection wells (DIW). DIWs go into the Boulder Zone, which is about 3,000 feet deep. Core borings will provide site-specific geologic and hydrogeologic data to evaluate properties of the Floridan Aquifer system at locations under consideration for ASR wells.
Storage capacity and cost estimates are from the Lake Okeechobee Watershed Restoration Project Integrated Project Implementaion Report & Environmental Impact State, published by the U.S. Army Corps of Engineers. That document indicated these are estimated costs and the actual price tag could be as much as 30% higher.