The health of the Everglades depends on restoration of the "river of grass," but outside scientists are worried that climate-change impacts are not being taken into account by those working on restoration/NPS file

While much has been accomplished with restoration of the Everglades, and billions of dollars of more funding are being lined up, the National Academy of Sciences continues to have concerns over the lack of climate-change planning being factored into what is viewed as the world model for large-scale ecosystem restoration.

"The one near certainty regarding Florida climate change is that temperature and sea level will continue to rise. Increases in sea level will alter the salinity and habitats in coastal and near coastal regions, and increases in air temperature will drive increases in evapotranspiration and decreases in runoff, unless compensatory changes in precipitation occur," reads an opening page of the 265-page 9th biennial review of Progress Towards Restoring the Everglades.

"However, changes in precipitation and resulting discharge will remain uncertain and highly variable during [Comprehensive Everglades Restoration Plan] planning and implementation. Progress is under way to increase the rigor in which sea-level-rise scenarios are considered in CERP project planning (e.g., coastal wetland and estuarine salinity changes), but analytical capabilities are limited by the tools presently available," it continues. "In contrast, minimal progress is being made in the use of precipitation and temperature scenarios in project planning. No clear signal of the direction of change is not equivalent to an expectation of no change."

It’s been more than two decades since Congress passed the Comprehensive Everglades Restoration Plan, which has been viewed as a groundbreaking law aimed at restoring America’s Everglades after decades of destruction. The project is seen as a way to restore, preserve, and protect the South Florida ecosystem while providing for other water-related needs of the region, including water supply and flood control. 

The Everglades wetlands span nearly 3 million acres, and within that are the 1.5 million acres of Everglades National Park and its 1.3-million-acre Marjory Stoneman Douglas Wilderness, the largest wilderness area east of the Rockies. But the landscape has been under siege almost since the first developers and large-scale farm operations reached South Florida, and brought with them plans to divert or dam the water that flows south from Lake Okeechobee to Florida Bay. All those efforts down through the decades altered the Everglades by changing its natural processes.

The CERP has called for surface water storage reservoirs and aquifer storage and recovery projects to potentially remove 240 miles of canals and levees to "restore the historic overland sheetflow (of water) through the Everglades wetlands." As envisioned, the restoration is not entirely wildlife-related. Rather, it's an ecosystem-wide endeavor that will benefit not only alligators, crocodiles, snakes, birds, fish and vegetation, but also South Florida's human populations.

Under the ongoing restoration plan that involves federal, state, tribal, and local stakeholders, sections of the Tamiami Trail have been raised to allow flows of water to continue south through Big Cypress National Preserve and the neighboring national park and into Florida Bay, and there have been other projects to better improve water flows south from Lake Okeechobee and to conserve water.

But at the same time, the present concerns being voiced by NAS are nearly identical to the ones it raised four years ago.

"The committee remains unconvinced that the current, individual, project-level planning approach is an effective means of reassessing the systemwide, scientific-guiding vision for restoration in light of the extended expected timeframe for completing the CERP), changing system conditions, and the evolving understanding of the future Everglades ecosystem," the NAS's committee assigned to monitor the restoration progress said in its Seventh Biennial Review of the massive project released in 2018. The planning does not seem to be taking the impacts of climate change, such as sea level rise, hotter temperatures, possible changes in rainfall, into consideration, that review said.

The health of Big Cypress National Preserve also depends on Everglades restoration/NPS file

In the most recent review, released in late December, the NAS team stated that the U.S. Army Corp of Engineers and the South Florida Water Management District "should proactively develop scenarios of future precipitation and temperature change, including changes in variability, and a strategy to use them to inform future project planning decisions and ensure more reliable project performance."

More so, the NAS review said, "[T]he work being conducted for the CERP Update provides a critical opportunity to examine the functionality of the system as a whole, but whether or how climate change analyses will be included in this work remains unclear. If not included as part of the CERP Update, additional analyses should be conducted outside of this process. These system-level climate change analyses will inform priorities for the remaining unplanned CERP projects and adjustments to system operations and will illuminate potential restoration actions that may be needed to enhance ecosystem resilience, either within or outside the CERP."

At The Everglades Foundation, Dr. Steve Davis said the NAS reviewers "have echoed the climate change sea-level rise issue a number of times over the years in their biennial reports. That drumbeat is increasingly louder, but it's also more resolute and more focused."

"In the past, they've talked about how climate change is already affecting the ecosystem," said Davis, the foundation's chief science officer. "We've talked about the need to incorporate sea-level rise and changes in rainfall abundance and seasonality. To varying degrees, those recommendations have been incorporated into restoration planning, but not at sort of the enterprise scale."

Davis said that during the early stages of the restoration work there wasn't much focus on future climate-change impacts because modeling by the Army Corps and the water district relied on historic rainfall and sea-level behavior.

"So we have a period of record that has very wet years, very dry years. And their thinking was, 'We captured, in essence, the varability that we need,'" he said during a phone call last week. "And some of the earlier reports said, 'Well, that's not enough, we need more and we need to also be modifying boundary condition for South Florida,' which is the ocean and, and we need to look at scenarios of sea-level rise. And they've started to incorporate that into some of the more recent restoration planning efforts."

The latest NAS report did open by noting the "record funding" for Everglades restoration that is expediting progress and expanding its geographic reach in South Florida.

"In 2022, six CERP projects [were] under construction, one project and one major project components have been officially completed, and the new Lake Okeechobee Systems Operating Manual was released. Several projects are nearing completion in the next 2-3 years," the review noted. "The Everglades restoration program is exhibiting impressive momentum with three additional CERP projects expected to begin construction in the next two years. This implementation progress places the restoration at a pivot point with increasing demands associated with project- and system-wide operation and adaptive management, as well as with planning and implementation of remaining projects. An ambitious proposed implementation schedule (the Integrated Delivery Schedule) is being realized, and the Central Everglades Planning Project —the key project in the restoration of the central Everglades— continues to make impressively rapid implementation progress."

Nevertheless, the NAS concern over insufficient data being integrated in terms of climate change was clear.

"Systemwide analysis of climate change on CERP performance is essential to assess the robustness of the restoration effort to possible futures and support program-level decision making. The work being conducted for the CERP Update provides a critical opportunity to examine the functionality of the system as a whole, but whether or how climate change analyses will be included in this work remains unclear," the reviewers pointed out.

"The lack of [Army Corps] guidance on the use of accepted information related to changes in precipitation and air temperature in quantitative analysis as part of project planning leads to future vulnerabilities to climate change and variability as CERP projects come on line," they added. "The science of global climate change is mature and rigorous, and many other water resources planning projects, in the United States and globally, routinely use climate-change scenarios to examine project performance under a range of future conditions. The USACE has progressively advanced guidance on the consideration of sea-level change in its activities, but the success of the CERP also relies on understanding the effects of other climate-change impacts. To reduce future vulnerabilities, the committee urges the [Army Corps] to develop guidance on the use of climate-affected hydrology data for civil works studies discussed in the [Army Corps] climate action plan, which was anticipated in 2021.

"... The lack of guidance on the use of quantitative approaches to considering climate change and variability in hydrologic analyses fundamentally limits the potential success of CERP investments in ecosystem restoration."