Our beaches need more …sand.

Yes, really! As the global climate crisis  rages on, rising sea levels and more natural disasters are covering up and washing away our sandy beaches.

If we don’t do anything about it, we’re on course to lose almost  half of them this century! So as the apex, big brained,  planet-running head honchos, humans have used our massive intellect to come up with a genius solution: add sand to the beach. Now, you might be thinking:  Doesn’t sand come from the beach?

Well, yeah. But it’s also in nearby rivers  and at the bottom of the ocean. So we’ve been moving the sand from those places to the beach fronts that are running low.

And while it helps us keep the  beaches where we want them to be, it comes with its own set of consequences. So let’s talk about the pros and cons of bringing sand back to the beach. [intro music] So as you may have heard, sea levels are rising. Thanks to climate change!

Higher sea levels aren’t  just covering up the beach. They’re also carrying away sand with every wave. Researchers think that by the year 2100, erosion could threaten the very existence of most of the sandy beaches on Earth.

But we don’t have to take this  lying down on our beach towels. We can offset that loss by taking sand from places like sand pits or estuaries, and putting it on a beach. It’s called beach nourishment.

And this is nothing new. We’ve been doing it for more than a hundred years. In 1923, we re-sand-ified the  beach on Coney Island, New York.

In 1978, we refilled Miami Beach in Florida. And throughout the years, we’ve topped off beaches all over Asia, Europe,  North America, and Oceania. And it’s not just to make sure  our favorite tourist spots have enough room for all our beach chairs.

All that added sand can  take away some of the energy that an approaching wave brings to shore, kind of like a shock absorber. And since we tend to build a lot  of things right along the water, hurricanes and other natural disasters can completely wipe out all  our buildings and stuff. But the power of sand is enough to protect us from the most powerful forces on Earth.

Like, remember Hurricane Sandy? It completely destroyed the infrastructure where beaches hadn’t gotten  re-sandified in a while. But coastal areas with nourished  beaches were way better off, and had no homes destroyed  during Hurricane Sandy.

And no, the irony of that  storm’s name is not lost on me. So this practice of putting gobs of extra sand on our beaches is life saving. We can reduce the impact of deadly storms and save sandy beaches from disappearing.

It definitely has its benefits. But, uh …they might be short term. Waves and storms will continue to wear the beaches away, so you have to keep adding more whenever the supply gets too low.

The good news is that after  the first batch of sand, you only need a fraction of that amount when you go to re-nourish the same spot. So if you stay on top of it, keeping the beach where you want it is entirely possible. How large that fraction is, though, depends on what sand you  used to nourish your beach.

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Not all sand, or even all beach sand, is the same There are white sand beaches and volcanic beaches and everything in between. And color is only one thing that differentiates one kind of sand from another. Sand grains can be different sizes too.

The size of each grain has a big influence on its long term durability on a beach. Smaller, softer, more worn down sand that you dream of when you  plan for that beach vacation gets carried away more easily than coarser sand does. So I’m sorry to say that it makes more sense to reload beaches with the rough stuff.

But at least your tootsies  get some good exfoliation from walking along those beaches. And there’s another part of the beach experience that we need to talk about too, which is all the animals that live there. There’s a lot more to a beach ecosystem than seagulls and seaweed!

So you want the sand that you use to be similar to what it’s replacing, because all of the critters that live there chose that specific beachfront location for the habitat that they’re best suited to. Think of the baby sea turtles that don’t want to be eaten before they make their big  voyage to the open water! And the clams that need to dig  through that sand without arms!

Beach nourishment has a  huge impact on the organisms that live in the sand, and that’s true of the spots where we steal the sand from as well. A ton of particles get kicked up in the process of taking sand from the bottom of the ocean. And all of that debris floating  around in the water decrease s the amount of light that the plants and corals around there get to soak up.

That stresses them all out, and sometimes even buries them. This has caused problems in threatened coral reefs near Puerto Rico and critically threatened seagrass in Spain. And even the plants and corals that survived were changed by the whole experience.

They couldn’t photosynthesize as effectively and their growth was stunted. So this may not come as a surprise, but you can’t just take a large chunk of nature and expect everyone living there to go about their business as if nothing happened. What might be a bit more surprising is the fact that the animals living along the shoreline getting nourished also are at risk from the whole process.

Let me repeat that. The animals that live in the habitat that we’re trying to preserve are being harmed by the preservation of their habitat. One reason is pretty straightforward.

Dumping a bunch of sand on top of an already existing ecosystem  buries whoever was living there, since we can’t exactly let all the clams know to go elsewhere for the afternoon while we renovate their homes. But if we dig deeper, we uncover more problems. Birds and fish that eat plants and animals that live on the shore can’t  get to their food anymore.

Not just because they’re buried. But also because the new sand  might be different enough from what was there before that  their beaks can’t penetrate it. So even if you survived the big sand dump, your way of life is totally  different than it used to be.

This was observed in North Carolina, where birds, fish, and clams  all struggled to stay alive after their home beach was re-sand-ified. Surf-fishes hunt for clams that are  a different color from the sand. But after their beach gets refreshed, they may be surrounded by sand that’s a different color than it used to be and is sometimes full of empty shell bits.

So they may go hunting and keep  coming up with empty shells. And things aren’t any better for  the clams that don’t get eaten. Since the newly nourished sand is softer than what they’re used to, they have a harder time digging down into it for their protection.

That makes them more prone to getting swept away by waves into the wide open ocean. So pretty much everywhere that we do it, beach nourishment changes the ecosystem. And even when we’re trying to save their habitats, we end up killing a lot of plants and animals.

We’ve got a bit of an ecological  trolley problem on our hands. It’s not a black and white,  good or bad situation. We have no way of knowing how many organisms would die from climate  crisis-related habitat loss compared to how many die from beach nourishment practices.

And habitat loss caused by the climate crisis may not be reversible, while nourished beaches could  become more habitable again after about four years. Whether or not we add this sand to our beaches, a significant number of  lives will probably be lost. And we caused the climate crisis, so it’s kind of our problem to fix either way.

So, what do you think? Is beach nourishment the way to go? Let us know in the comments,  and thanks for watching! [ OUTRO ]