Delray Beach on Florida's East Coast is a bustling tourist hub. But because of projected climate change-related sea level rise, it is facing some sobering choices (as are other coastal communities bordering the Atlantic and Gulf of Mexico).
City planners in Delray have outlined four options to deal with the inevitable rising tides that have already begun to sporadically inundate portions of the city.(Florida has experienced five to eight inches of sea level rise in the last half century and could conceivably face three more inches in the next 30 years.)
Here are Delray's four options, from which other coastal communities no doubt will also have to choose.
First off is "stand and defend." This protective strategy would entail construction of dikes, sea walls, and pumping stations as well as engaging in beach replenishment where erosion occurs despite humans' best efforts.
Delray planners rate this the most likely immediate approach and an effective one for a long time, provided national policy is successful in greenhouse gas emission reduction that leads to mitigation of global warming. Even if climate change is slowed -- and Delray is promoting carbon emission curbs towards that end -- erecting protective barriers carry risks. Diversion of tidal flows can destroy natural areas and subsequently cause increased coastal vulnerability. In any event, Delray Beach and other Florida municipalities are looking for guidance from the Dutch, who for centuries have structurally prevented the sea from overrunning their low-lying country.
The next option is accommodation, or for lack of a better descriptive term, "buying time." This would consist of such measures as elevating roads and the height of coastal structures to make them more flood resilient, and enhancing existing wetlands where possible to slow the advance of excess sea water.
A third option would especially come into play if humanity falters in an effective response to global warming and conditions significantly deteriorate. It is dubbed "retreat" or "get out of the way." This would involve relocation of beach houses further inland, with just how far determined by topography. While this might seem a remote possibility for so densely a populated area as Florida's coastline, such drastic actions are already being discussed in Southern Louisiana. It is there that Gulf waters are submerging the state's protective wetlands at an alarming clip.
Finally, if all else fails, there is the alternative of "avoidance" or "staying out of the way." That means removing any permanent structures and prohibiting further development in "high hazard" zones, which would be returned to nature.
Such anticipatory planning and emission reduction strategy are all well and good, but U.S. Sen. Bill Nelson, D-Fla., notes that a lot of people have their "heads in the sand" despite Florida being at ground zero for sea level rise.
At the close of a recent Senate Democrat all night Capitol talkathon on climate change, Nelson warned that if it is business as usual, much of Florida will end up under water.
Thankfully for residents of Delray Beach, it is not business as usual.