DNR: Rattlesnake Ridge landslide not speeding up; seismometer stolen
UNION GAP, Wash. - A few months ago, Union Gap and Yakima County declared a state of emergency because of the Rattlesnake Ridge landslide. Today, the 20 acres of rock is still making its way down, but it's not thought of as the disaster waiting to happen it once was.
“The landslide rate has not changed. It's about 1.6 to 1.7 feet per week,” Stephen Slaughter with the Department of Natural Resources said.
It's been sliding for a little more than four months. So, the giant mass of rock has moved about 25 to 30 feet.
Slaughter is one of the geologists who still monitors the slide.
He said they come out here once or twice a month to make sure all the data-gathering equipment is still working.
“Being out here in the field is important but we have instrumentation all over this landslide that allows us to see what's going on in real time. Which is probably more valuable in some ways than being out here to see it,” he said.
Slaughter said they get updates about every 30 minutes and have 22 survey points that track the data.
They also have seismometers on the ridge to check for any movement.
However, they're going to have to work with one less seismometer going forward.
“Someone came up and drove up on the landslide above and stole $18,000 of equipment that we're using to monitor public safety,” Slaughter said.
The Yakima county sheriff’s office has said going up on the ridge is illegal and encourages everyone to stay away.
“It's considered trespassing. We encourage the general public, if you see people up there, please contact the sheriff's office,” Chief Ed Levesque said.
Slaughter said they can still do their job without the missing seismometer, but it's just unfortunate that one of them was stolen.