- November 22, 2024
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Whether or not they believe sea levels are rising, or at what rate, coastal property owners should prepare for the coming flood of local, state and federal regulations.
And inland property owners may wish to keep a wary eye on what's going on, too. Environmentalists want to enable coastal wetlands to migrate landward, requiring undeveloped property for that to work.
Government agencies are increasingly taking seriously the cautions of experts such as University of Florida coastal law expert Thomas Ruppert, who warns, “Ignoring future sea level rise in our policy development and land use planning today is going to be far more costly in the long run than implementing good policies today.”
While relatively few local governments have yet to address sea level rise (SLR) issues with policies and regulations, several along the Gulf Coast are increasingly moving in that direction.
Punta Gorda now has separate SLR vulnerability and adaptation plans, and Lee County is pursuing funding for a similar study, but already requires SLR be considered with infrastructure plans. Collier's land development code requires an analysis of shoreline development projects demonstrating the impact of a six-inch rise in sea level.
And while a federal study claims that sea levels along much of the Florida coast rose 7-9 inches during the 20th century, that shift in policy direction is coming without policymakers making basic assumptions as to how much SLR is expected over time.
This may explain why: SLR estimates are literally all over the map ranging from a few inches to 17.7 inches by 2050 and from 40 inches to 16.5 feet by 2100.
The most notable early estimate of seven to 23 inches by 2100 comes from the International Panel on Climate Change (IPCC) made just two years ago. But that one did not account for the increase in polar ice sheet melt from Greenland and West Antarctica found in new satellite data. More recent estimates have grown, prompting scientists to argue that the 2007 IPCC estimates are too low.
An estimate of how SLR translates into landward movement of the shoreline, known as the “Bruun rule,” predicts a one meter rise (about 40 inches) would generally cause shores to erode 50 to 200 meters along sandy beaches even if the visible portion of the beach is fairly steep.
But the Bruun rule is now being discredited in the coastal science community, and now some experts claim a better rule of thumb is one foot of SLR equates to 500 to 1,000 feet of receding shoreline. That should make any waterfront or key property owner nervous, and is now one more reason SLR is starting to get more attention, at least by regulators if not coastal property or business owners.
But a recent “Symposium on Land-Sea Interactions in Southwest Florida”, hosted by the Marine Policy Institute at Mote Marine Laboratory in Sarasota, was sparsely attended.
Frank Alcock, director of the institute, says he was disappointed with the total attendance but also that few came from beyond Sarasota. “We did not get all the folks there,” he says, adding, “I don't think it's on the radar.”
Fewer than 60 people were seen at any time during each of the two days of the meeting. And close to a third were presenters, mostly academics or government officials. Two presenters came from the private sector — planner
Pam Truitt and Rex Jensen, president of Schroeder-Manatee Ranch, developers of Lakewood Ranch.
Just a few local government officials showed up including three Sarasota county commissioners, a few county environmental staffers and two Sarasota city commissioners.
No city or county planners attended, according to institute staff.
Jon Thaxton, chairman of the Sarasota County Commission, presented his views of sea level rise and its land planning implications.
Referring to hurricane surge maps showing development was directed to coastal flood and surge-prone southwest areas of the county, Thaxton admitted that was a big mistake saying, “We put all of the development in all the wrong places.”
Yet while saying development needs to be relocated from the coast to upland areas, he says, “We're not going to take the hurricane flood zones and turn them into national parks.”
Those surge maps look markedly worse when SLR scenarios of 30 to 120 centimeters are factored in on top of Category 1 to 5 hurricane surges as was done by Tim Frazier, now assistant professor of geography and bioregional
planning at the University of Idaho and a symposium presenter.
But Thaxton sees no need to move the urban services boundary eastward from Interstate 75, saying he's skeptical of the more extreme SLR predictions. But other government officials and planners who saw Frazier's July presentation want to look at new boundaries in light of the new research.
Policy conundrum
Thaxton's admissions highlight the major policy conflicts for decision-makers.
Should government agencies purchase developed or undeveloped beachfront property if they believe it will be inundated in 20 or 50 years? Will there be enough suitably zoned inland property to accommodate a massive migration if Miami and Naples are inundated sooner?
And should beachfront property owners expect more or less beach renourishment, or more or less armoring regulations to protect their property?
Property and business owners might want to pay better attention, but so far it appears they're not.
Pam Truitt, the symposium's private sector planner out of Sarasota, surveyed business people about SLR for her symposium presentation and found little knowledge or concern.
Many people seem to think they can put up protective walls if need be. At first, that logic would seem to fly in the face of Sarasota County's no hardening policy, but the county has already permitted seven adjacent Casey Key property owners to harden their shoreline.
But many more such permit requests could end up on city and county agendas if sea levels rise. More property owners with fortunes at stake may form bigger coalitions to get their point across, according to Sarasota coastal engineer Kristey Tignor. She's seen the battles play out along the Gulf Coast.
Beachfront owners who benefited by public beach renourishment projects may find increasingly expensive sand shuffles fewer and far between.
Jim Beever, a planner with the Southwest Florida Regional Planning Council, says the half-life of beach renourishment projects is getting shorter, and will get shorter still due to the compounding effects of SLR and predicted greater hurricane intensities. That scenario translates into a need for more frequent renourishments.
At some point, it may no longer be economical and if beachfront owners can't harden the shoreline either, then options become limited to moving the house landward (often limited by front yard setbacks or underground utilities) or abandoning it all together.
Heading inland presents its own set of bigger growth management policy conflicts.
'Open it up'
A new state law, Senate bill 360, removes state reviews encouraging dense urban land areas to be more dense, but only at local governments' discretion.
One reason for the legislation is to combat global warming, the often cited contributor to sea level rise. But most of those dense areas are along the coast such as Clearwater, St. Pete Beach, Longboat Key, Fort Myers, Fort Myers Beach and Naples.
Some, like Jensen, whose 10,000-acre Lakewood Ranch is eight miles inland on the Manatee-Sarasota county line, thinks it's time to get rid of urban boundaries and “needs analysis” requirements in state growth management laws.
Jensen, who has more expansion plans, argues, “The only place you can buy is in these [coastal] areas you shouldn't be in in the first place. We need to open it up to more consumer choice right now while it's cheap.”
But Thaxton counters, “I think the expectation of moving all these people out of these [coastal] zones is an unrealistic expectation. I don't think it's going to happen. I do admit that we have one policy that says move northeast and another that says move west.”
But that expensive, decade-long “move northeast” policy, is so full of regulatory strings that it makes Jensen's blood boil. “It's too big of an issue for them to deal with,” he says.
Such conflicts are noted in “An Assessment: Policy Tools for Local Adaptation to Sea Level Rise,” prepared by Barbara Lausche, deputy director of Mote's Marine Policy Institute.
The Sept. 15 working draft notes that “Current growth plans and development projections have the majority of residents clustered near the coast or in flood plains, reinforcing current growth patterns.”
Lausche adds: “Government has the responsibility to begin to promote incentives.”
The report outlines federal, state and local policies to address SLR, including conservation easements, transfer of development rights, land acquisition, habitat preservation rules and rolling easements, where private land becomes public as the sea rises, but which UF's Ruppert says faces legal hurdles here due to Florida property rights laws.
Ruppert is pushing for changes to be made to the state's coastal construction control line based on SLR.
Property and business owners will be well served to start paying attention.
Rising sea erodes beaches, drowns wetlands, submerges low-lying lands, exacerbates coastal flooding, and increases the salinity of estuaries and aquifers. Coastal communities must ultimately choose between one of three general responses, each of which is being pursued somewhere in Florida:
• Armor the shore with seawalls, dikes, revetments, bulkheads, and other structures. This approach preserves existing land uses, but wetlands and beaches are squeezed between the development and the rising sea.
• Elevate the land and perhaps the wetlands and beaches as well. This approach can preserve both the natural shores and existing land uses, but often costs more than shoreline armoring.
• Retreat by allowing the wetlands and beaches to take over land that is dry today. This approach can preserve natural shores, but existing land uses are lost.
Source: http://risingsea.net/ERL/FL.html
