Satellite imagery can show which Southern California households are likely following watering rules during the drought — and which are not.
The data from the Sentinel-2 satellite does not come from a local water agency, but from an amateur. Ben Kuo enjoys using high-tech tools to understand natural disasters.
“I don’t think anyone has thought of using that same data to track water users,” he says. “[It] It’s amazing to me that from the space you can actually see what someone is doing in their garden.
The Cal State Channel Islands geographer and science teacher has become an important Twitter for information on Southern California disasters. But before that, he was just a father, trying to satisfy his son’s curiosity.
“He was interested in listening to firefighters and police radio when he was in elementary school, of all things,” Kuo says of his son. After much trial and error with the scanner, “it has become more than just a hobby for me.”
In 2017, when Hurricane Maria devastated Puerto Rico and wiped out the small island nation of Dominica, Kuo says he used an amateur radio to relay messages between residents and the US Embassy, which eventually dispatched helicopters to rescue American citizens from the wreckage.
“They had no phone, they had no internet, they had no communication. And the world didn’t know that,” he says.
Kuo found another role for himself later that year when Thomas’ fire broke out much closer to his home in Thousand Oaks in Ventura County. It’s still one of the 10 largest wildfires in state history. Kuo listened to police and fire scanners, and took the information he gleaned to Twitter, where reporters and fire-affected residents eagerly consumed it.
Then last year, he found 15 minutes of fame through a Washington Post article about his help in rescuing a missing hiker in the Angeles National Forest.
“Using satellite information,” he recalls, “I found the guy using only the photo of his feet.”
Kuo led the sheriff’s deputies to the right area to search for him. The hiker was airlifted out of the wilderness after 27 hours lost in the mountains.
The satellite data also helped Kuo demonstrate something else he’s passionate about: that humans have changed their environment.
“Many of the disasters that we see, and for which I participated in helping, [include] Forest fires [that] are influenced by climate [change],” he says. “Hurricanes… flash floods… they’re all tied together.”
The natural disaster of 2022 is worsening drought in the state. In June, after local water agencies told customers to reduce their water use, Kuo noticed something strange from a satellite he was monitoring.
“One of the things you can look at is called the ‘wetness index’,” he says. “And it just so happens that this satellite has enough [detail] that you can tell where things are dry or wet with much higher resolution.
Free and publicly available data allows users to zoom in to see a specific house and see how wet the yard is. A dry lawn may appear orange on satellite data. A household that flouts drought restrictions with lots of wet grass will appear blue.
Kuo says Camarillo is a great place to find drought-breaking people because their water-use rules are among the strictest in Southern California.
Residents are only allowed 15 minutes of outdoor watering once a week. Three violations can total a fine of $600. A fourth violation could mean the city significantly lowers your water pressure.
“We have a water patrol that travels during the day and evening at this point and monitors residents’ usage,” says Deborah Gallegos of the City of Camarillo.
While walking through a regional park in Camarillo, Kuo observes the dead brown grass that covers the hills of Southern California in the summer. “If you’re in the hills here hiking, you realize when things get dry here, how dry it is. And I don’t think when you’re inside your house with the air conditioning on, you realize how bad the drought is,” he says.
On his social media, he jokes about how his posts shaming some of the water-hogging households may not be popular with water consumers. But when it comes to controlling water use, he says desperate times call for desperate measures.
“If you remember, last year Governor Newsom said, ‘Oh, everybody conserves,’ and everybody kept using water. Voluntary restrictions aren’t that effective,” says he said, “We’re in a climate emergency right now. And we’re running out of water in Southern California. What do you do?”