Rebuilding Beaches Can be a Problem
Imagine you're in a beach it's flat it's white with pristine sand looks lovely right unfortunately many beaches don't look this way they're narrow with steep cliffs and waves breaking close to the property line there is a beach does the screening erosion in America about 80 to 90% of sandy coastlines have this problem so the government spends billions to expand some of the most rapidly eroding beaches in an effort to do to defend the coast but this effort well effective in that short-term can actually hurt beaches in the long run it's because every shoreline on the planet is subject to erosion beach erosion occurs when the waves and currents move sand from the coastline the loss of them makes the beach narrow and lowers its elevation this erosion becomes a problem when it reaches structures built by humans along the coast especially for beaches that generate tourism the visitor enjoy the sandy close about the cities and towns nearby want the revenue gained but the driving factor there is the beach a place like Miami beach wouldn't have the same draw if there weren't lots of sand in fact there was a time when it didn't look this way at all in the 1970s a seawall turned the beach in Miami into a narrower Strip but by the 80s the beach in Miami re emerge nice and wide how well coastal engineers rebuild it through a process called beach nourishment beach nourishment is a shore protection strategy to try countered the loss natural loss of sand. The typical way to do this is with dredging.
Boats dig upstands from a borrowed sight and move it onto the beach. You'll have a big pipe pump, and you suck up the sand, then it's transferred to the coastline where it is dumped or pumped out onto the beach, and then bulldozers move it around to try to mimic what natural beach was like before the project took place. The result is a lovely white beach the new profile will better defend the property line from damage during more intense weather like a storm surge flooding. In the United States beach nourishment is the primary strategy you used to protect coastal properties from risky erosion but there's a problem the perception doesn't last as a constant beating of waves and wind takes the sand away from the shore, and it soon looks like it did before the nourishment occurred. Every 2-8 years, on average, the nourishments need to be repeated like the beach in Florida. Lido beach, on the gulf coast of Florida, got emergency nourishment in 2018 after damage from storms reduced the beach to a narrow strip, but the beach had already gotten new sand 15 times since 1964. Lido key isn't an outlier. More than 200 of the 400 miles of critically eroding coastlines in Florida have received more nourishment. Across the United States, there have been nearly 3000 known nourishment events since 1923. The funding for these projects gets a little winky, but here's what's important: the federal government pays for many of these nourishments—up to 65% of the cost. State and local funds will make up the rest. However, not all beaches that want or need nourishment will get it. The Army corps of Engineers- the group that approves and designs nourishments- prioritize defending some beaches over others, based on the potential loss of value according to the ProPublica, the corps only funds nourishment where the expected benefit is two and a half times as high as the cost poorer communities won't often meet that criteria.
Such places like Miami Beach, Florida, and Ocean City, Maryland, are more likely to get a lot of nourishment/. They have the expensive shorefront developments that make the investment worthwhile. And for beaches that don't cut nourishment, continued erosion can lead to damaged or destroyed property. Nourishments are just about protecting Buildings but also protecting the economies tied to them and the beach considering the 200 million dollars spent on nourishment in Florida from 19955-2001. That might seem like a lot of money until you see the revenue from coastal tourism- it was 21.6 Billion in just one year in Florida. On Average, Florida's state generates more than 5 dollars of revenue for every dollar invested in beach nourishment, which is why nourishment is appealing. It makes economic sense.
However, they do present one major problem. According to research published by the American Geophysical Union, there is a feedback loop. Nourishments tend to happen along beaches that generally have expansive properties, and they also seem to drive development along the same shores, despite the risk of future erosion.
If you were in a place that had nourished its beach, the houses behind that nourishment project were significantly more extensive, in every case, than in a place that had never nourished its shoreline at all. The research found that areas with nourished beaches had homes that were about three times bigger than non-nourished ones, and this excessive development is a real problem because it's based on false security. According to the researchers, "beach nourishment may make or reduce the apparent impact of coastal hazards without changing the natural processes that drive them. Building more property in these areas only increases the potential damage for future erosion. So while beach nourishment projects property and local economies in the short run, they also trick us into thinking it's safe to build in places that aren't. Which sets up coastal communities for an ugly reckoning at the shore… sooner or later.