Feb 1, 2018 4 min read

When Washington residents Ken and Sandra Dyson woke up Jan. 15, they noticed something unusual in their backyard that wasn’t there the day before – a hole next to their in-ground swimming pool.

“When we first were looking out the window, we thought maybe it was a groundhog,” said Ken, who lives at the corner of Duncan Avenue and Fourth Street.

But when he went outside to look at it, he knew it was a sinkhole. In the next two weeks, he and his wife watched it grow to what it is now – about 4 feet in diameter and about 6 feet deep.

“We’re praying that it stops,” Ken said.

The same day they discovered it, Ken reached out to his neighbor Joe Manning, a Washington city councilman.

“He said, ‘Joe, I got this hole in my yard and I don’t know what’s causing it,'” Manning said Tuesday. “He said that the hole is getting worse and moving closer and closer to his pool. So, time is of the essence that we get this thing taken care of.”

The city’s engineer, Sarah Boyce of Widmer Engineering, said the sinkhole was caused by a collapsing storm sewer conveyance tunnel that runs underneath the Dysons’ pool.

Ken Westcott, Washington councilman and director of public works, said because of its age, the bottom of the 60-inch, brick storm drain is gone, causing the walls to collapse and creating the sinkhole. He said city engineers will record video in the drain to see how far the collapse goes beyond the sinkhole.

“Once we determine if it’s not collapsing further down, then we need to figure out how to fix the problem in this person’s yard,” Westcott said.

Westcott said the city faced a similar problem with the same storm sewer tunnel a few months ago when a hole developed on a vacant lot on the opposite side of Duncan Avenue from the Dysons’ home.

“We addressed a problem where we were able to secure a storm drain by pouring concrete in there to make sure there’s a bottom,” Westcott said. “We assumed once we fixed this problem it would go away, but unfortunately, this is a continuation of that problem.”

Manning said a fissure also developed on the side of the Dysons’ house, away from the sinkhole and closer to Duncan Avenue. He said it’s not as large as the sinkhole, but still a concern because it’s close to the Dysons’ house and in line with where the tunnel is.

Boyce said she’s concerned the top of the storm tunnel also may have collapsed, because it was “a pretty quick void that developed.”

The city is determining if it has an easement for the property because the engineers need to have a contractor dig up the tunnel and see if it’s collapsed farther down. Until they find that out, they won’t know how to proceed, she said.

“I can’t recommend something until we know what’s going on,” Boyce said. “It could be more extensive, but we really don’t know at this point.”

Dyson said he was encouraged by the city’s quick response to his concerns. He said that from what he’s seen so far, the city and engineers are “on it.”

“It’s just a shot you can’t call in two days,” he said. “They can’t do it overnight, and I understand that.”

He said he and his wife have lived in that home for about 30 years and that nothing like this has ever happened.

“The infrastructure is getting old in the city, and we’re all going to have to deal with it,” Dyson said.

“We’re just having to start here.”