NewsLocal News


New technology hopes to predict bluff failures before they happen

Posted at 6:11 AM, Jul 24, 2021
and last updated 2021-07-24 09:12:53-04

(KGTV) -- For years researchers have been studying the California coast, observing cliff erosion, and how it has changed over the years.

You may remember back in August of 2019, a beach bluff in Encinitas collapsed onto beachgoers and killed three of them. A year later, a part of that same bluff also collapsed.

It’s because of incidents like these that researchers at Scripps Oceanography have been spending years studying cliff erosion. But within the past month, they have been experimenting with new technologies. They are hoping to not only expand their coverage area but also, be able to predict when a cliff will fall before it does.

“You can see a rock wall that looks like solid rock but it will just fall over," shares Research Geophysicist Mark Zumberge, with Scripps Oceanography. He is the latest addition to a team of researchers, who are led by Adam Young, a Marine Geologist, whose research specializes in cliff erosion.

Zumberge shares that Young uses a tool called Lidar, which scans the face of a cliff with a laser, which in turn produces detailed pictures, and allows those studying the images, to see how much material came off. Zumberge says that data has been used to create a database for how quickly the cliffs are eroding, and where.

Two other members on the team study earth's crustal deformation. According to Zumberge, the two use sensors and GPS' to study the strain on earth's tectonic plates as they move. This data allows researchers to get an idea of when and where earthquakes occur.

But a month ago, when Zumberge was brought onto the team, he presented a new piece to their puzzle of tools- fiber optic strain sensors.

“We stretch this in a borehole," illustrates Zumberge as he holds a piece of fiber optic in his hands, "and we are essentially measuring the change of length in this fiber optic as the ground moves.”

The tool generates 200 samples of data per second as it measures the tiniest of movement. It produces data in real-time as opposed to the other tools, which can take weeks, months, even years.

The fiber optic strain sensor works by sending a laser light into the fiber optic, electronics then analyze the light and detect any change in the height of the cord, which can be as small as nanometers. That change of height in the cord, or any movement to the cord, corresponds to signifying any movement within the cliff which could be caused by either rainfall or groundwater.

Zumberge says it can essentially find any signal that a bluff could slowly be collapsing.

While in the laboratory where they assemble the technologies, Zumberge reflects on recent cliff failures like the one in 2019, “It’s clearly something that is of societal relevance, people lost their lives.”

However, the new tool is not studying our California cliffs just yet.

The team is waiting on the passage of bill AB-66 which is looking to accelerate sciences like the tool Zumberge is working on, as well as create a possible warning notification system. Zumberge says while they are not the first group to attack this issue, he is hoping they will be able to create the most accurate data.

“Hundreds of miles of coastland in California and cliffs," expresses Zumberge, "and it would be great to get a better understanding of how we can tell where the riskiest places are.”

If the bill passes, the team hopes to observe two areas with the fiber optics, and possibly other technologies the team is already working with. The first would be along the cliffs in Del Mar.

The second location would be at Beacon Estate Beach in Encinitas, “There’s an access point of the beach that is built on top of an old landslide," describes Zumberge, "and we would like to figure out how it is moving. Is it continuously creeping? Will it stay still for a while, will it move?”

Those are the locations they are hoping to start at, but Zumberge says in the future, these tools could be used for other things, such as seeing if they can potentially track earthquakes or forewarn others on tsunamis.

Those are just some of the many questions they hope to answer soon. Zumberge shares the reality for most of the people who frequent California shores, "People don’t always listen to warnings as we have seen."

When asked if he believed his technology would one day serve to be that warning for others, he said, "Yes we hope. We will see.”

The bill is waiting to be heard by a committee on August 16th. If it passes, their work will be funded for three years, beginning January 1st, 2022.