Scientists study impact to beaches after recent pounding from rainwater

Scientists are sifting through sand in Santa Cruz to see how recent rain is changing local beaches.

“Now we’re hoping to identify exactly how much sand was transported during the single event,” said U.S. Geological Survey Coastal Geologist Partick Barnard. “So we that we know where that falls on the whole range on evens like this and similar to this.”

Scientists believe the massive storm transported about two thousand dump trucks worth of sand.

“This particular storm, probably the amount of discharge out of the river only occurs once every 10 years or so,” said Barnard.

Scientists rode up and down the mouth of the San Lorenzo River on watercraft equipped with GPS units and an echo sounder. They collected millions of measurements above and below the water.

They’ll use the information to make a 3D map to better understand how El Nino and other winter storms will affect the coast and evolve beaches over time.

“And even further out, we can build better models to look at the impacts of climate change,” said Barnard. “How discharge may vary in the future and then the transport of sand to the coast will vary in the future,” said Barnard. “Ultimately what’s going to happen to our beaches.”

The U.S. Geological Survey said in some cases all of the sand discharge could cause a lot of erosion amongst other things.

“Well it’s not good for the harbor because the boats can’t come in and out,” said Ellen Gallagher of Santa Cruz.

On the other hand, all of the new sand in the systems is a positive because it will move onto other beaches, making them larger and more sustainable.

“Well if the beaches weren’t as beachy, people wouldn’t come to enjoy recreation,” said Santa Cruz resident Grace Voss.