The sea level is rising three to four times faster along the East Coast of the U.S. than other parts of the planet, impacting big cities including NYC, Boston, Philadelphia, Baltimore and the already Hurricane Sandy-hammered coastline of New Jersey.
Which has one small town in the Garden State—Highlands, located on a peninsula jutting into the Atlantic Ocean 50 miles south of Manhattan—preemptively thinking about trying to save itself by “lifting” the entire downtown by 11 feet. The 200-to-250-million-dollar project is still just talk and would take a few years to complete. But folks in Highlands, a town of just 5,000, are anxious to ward off the future impacts of any more Sandy-like flooding and storms made worse by higher sea levels.
The big question is not necessarily the budget, but would 11 feet be enough to save it next time?
Estimates of sea level rise along the East Coast by 2100 range anywhere from four to 23 feet. While the turn of another century seems far off, many born today will still be around to watch the consequences of today’s actions—or lack of them.
The U.S. Geological Survey analyzed tides along the 600-mile stretch from Cape Hatteras, NC, to Boston and watched sea levels rise by about 1.5 inches a year between 1950 and 2009; on average, global sea level rise during the same time has been about half that.
The biggest immediate threat is that the kind of flooding the East Coast used to see every three or four years is now happening three and four times a year.
The trickiest part for scientists trying to predict sea level rise is if they can determine, for example, how much sea level rose during a 1,000-year period. What they can’t say with precision is if the increase came in 100 years, or took the full 1,000.
Maps of the New Jersey coast today suggest that Highlands could gain a bit on the climbing seas by piling up dredged materials such as chunks of concrete and barges full of gravel and dirt underneath them. If it looks like that might work, presumably other small towns along the coast would follow suit by essentially sticking telephone books under themselves to try and “lift” up and out of harm’s way. The expense of raising the entire East Coast is staggering; Actually razing low-lying towns would be more cost-effective.
This notion of lifting towns strikes me as a very temporary solution. Big storms and erosion will invariably eat away at the newly built platforms, especially if seas rise by the extreme prediction of 20-plus feet by 2100.
Another tropical storm the size of Sandy would most likely undo much of the effort. And the Army Corps of Engineers, which would do the construction, can’t be expected to lift the entirety of the East Coast. And I don’t see the federal government financing the plan.
As Highlands’ mayor told the Asbury Park Press: “The cost of doing nothing ultimately would be much higher.”