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  • Imagine you're on a beach.

  • It's flat, it's wide. With pristine sand.

  • Looks nice, right?

  • Unfortunately, many beaches don't look this way.

  • They're narrow, with steep cliffs, and waves breaking close to the property line.

  • This is a beach that's experiencing erosion.

  • In America, about 80 to 90 percent of sandy coastlines

  • have this problem.

  • So the government spends billions to expand some of the most rapidly eroding beaches in an

  • effort to defend the coast.

  • But this effort, while effective in the 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 waves and currents remove sand from the shoreline.

  • The loss of sand makes the beach narrower 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 visitors enjoy the sandy coasts while the cities and towns nearby enjoy 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 narrow strip.

  • But by the '80s, the beach in Miami re-emerged

  • nice and wide.

  • How?

  • Well, coastal engineers rebuilt it through a process called "beach nourishment."

  • Beach nourishment is a shore protection strategy to try to counter the loss, the natural loss of sand.

  • The typical way to do this is with dredging.

  • Boats will dig up sand from a borrow site and move it onto the beach.

  • You'll have a big pipe pump and you'll suck up the sand.

  • Then it's transferred to the coastline.

  • Where it's dumped or pumped out onto the beach

  • and then bulldozers move it around to try

  • to mimic what the natural beach was like before the project took place.

  • The result is a nice wide beach.

  • The new profile will better defend the property line from damage during more intense weather

  • like storm surge flooding.

  • In the United States, beach nourishment is the main strategy

  • used to protect coastal properties from risky

  • erosion.

  • But there's a problem.

  • The protection doesn't last.

  • As the constant beating of waves and wind takes the sand away

  • from the shore.

  • And it soon it looks like it did before the nourishment occurred.

  • Every 2 to 8 years, on average, the nourishments need to be repeated.

  • Like this beach in Florida.

  • Well this morning, Lido Beach is under a local state of emergency

  • Just look at how powerful the wind was earlier today

  • problem getting worse by the hour.

  • Lido Beach, on the Gulf Coast of Florida, got an 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.

  • And Lido Key isn't an outlier.

  • More than 200 of the 400 miles of critically eroding coastlines in Florida have received

  • one or more nourishments.

  • And across the United States, there have been nearly 3000 known-nourishment events since 1923.

  • The funding for these projects gets a little wonky, but here's what's important: The federal

  • government pays for a lot of these nourishments.

  • Up to 65% of the cost.

  • State and local funds will make up the rest.

  • But not all beaches that want or need nourishment will get it.

  • The Army Corps of Engineersthe group that approves and designs nourishmentsprioritizes

  • defending some beaches over others, based on the potential loss of value.

  • According to ProPublica, the Corps only funds nourishments where the expected benefit is

  • 2 and a half times as high as the cost.

  • Poorer communities won't often meet that criteria.

  • So 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 make the cut for nourishment, continued erosion can lead

  • to damaged or destroyed property.

  • Nourishments aren't just about protecting buildings, but also protecting the economies

  • tied to them and the beach.

  • Consider the 200 million dollars spent on nourishments in Florida from 1995-2001.

  • That might seem like a lot of money, until you see the revenue from coastal tourismit was $21.6 billion

  • in just one year — 2001.

  • On average, the State of Florida generates more than 5 dollars of revenue for every dollar

  • invested in beach nourishment.

  • Which is why nourishment is so appealing.

  • It make economic sense.

  • But they do present one major problem.

  • According to research published by the American Geophysical Union, there is a feedback loop.

  • Nourishment tends 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 larger, in every case, than in a place that had never nourished

  • its shoreline at all.

  • 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 actually mask or reduce the apparent impact

  • of coastal hazards without changing the natural processes that drive them."

  • In fact, building more property in these areas

  • only increases the potential damage from future erosion.

  • So, while beach nourishments protect 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.

Imagine you're on a beach.

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