PORT ANGELES — The city’s Fourth of July parade will proceed as planned at 6 p.m. today after state Department of Transportation workers finished filling a 280-square-foot, 8-foot-deep sinkhole at a major downtown intersection Tuesday.
The extent of the void under U.S. Highway 101 at the Lincoln-First streets intersection was not known until the state Department of Transportation drilled exploratory holes Monday following a problem with an asphalt patch that kept sagging, said Steve Russell, Transportation’s Area 3 maintenance and operations superintendent.
A portion of the northbound lane of Lincoln was closed and 101 traffic detoured east down Eighth to Race Street while the problem was addressed, city Public Works and Utilities Director Glenn Cutler said.
Blocks of Lincoln Street have up to 30 feet of fill under them, and a Peabody Creek culvert-tunnel routes the creek under Lincoln and down to the city’s waterfront, Cutler said.
The northbound lanes were reopened late Tuesday afternoon.
The fix ensured the city’s Fourth of July parade will proceed without alteration, the parade organizer, Port Angeles Regional Chamber of Commerce Executive Director Russ Veenema, said Tuesday.
Had the Lincoln Street lane still been closed, larger trucks would have joined the procession on First Street because they would have had difficulty negotiating the left turn from Lincoln, Veenema said.
The parade will start as scheduled at 6 p.m. at the corner of Fourth and Lincoln streets and wend its way to First Street before turning west on First, Veenema said, adding the parade has more than 90 entries.
Parade announcers will be on Lincoln at Veterans Park, at the Conrad Dyar Memorial Fountain at First and Laurel streets, and in front of Country Aire natural foods grocery on First at Oak Street, Veenema said.
“We were in the mode where we could handle it either way, so there was no stress,” Veenema said.
State Transportation workers on Monday discovered the 20-foot-by-14-foot, 8-foot-deep sinkhole — a void the size of a large living room — under the intersection at which U.S. 101 makes a critical turn in central Port Angeles, Russell said.
The workers finished pouring the equivalent of three dump-truck loads of controlled-density fill — an amalgam of concrete and gravel — by about 4:15 p.m. Tuesday into what Russell called the “void” under the street.
The mixture was poured through two of seven test holes that had been drilled in the street to assess the extent of the problem.
“There’s so much under here, we can’t pinpoint what caused it,” Russell said.
He said old drainage and sewer lines also are under the street, and that the fill, made of sandy material, might have escaped into the culvert much like sand trickles through an hourglass.
Russell said other sinkholes could develop on Lincoln.
“This can happen on any highway where culverts are under it,” Russell said.
“They get old, and that’s why we’re here — to catch it before it causes a problem.”
A portion of Lincoln Street contained a trestle that was filled in and covered first with 9 inches of concrete and then, eventually, with 12 inches of asphalt, Cutler said.
For example, 30 feet of fill was to be “located” at Lincoln and Third streets, according a March 27, 1914, article on a pending downtown regrade project in a report in the now-defunct Port Angeles Olympic Leader newspaper.
Cutler also said Peabody Creek once meandered to the waterfront from where Peabody Creek RV Park is located off Second and Lincoln streets and cut beneath where the The Gateway transportation center is now located.
The culvert redirected the creek so it came down Lincoln and discharged near Railroad Avenue and Lincoln, he said.
“A lot of that is fill material that’s down there,” Cutler said.
“What happened is, we suspect some of the material got washed away,” he said.
“We don’t think it was a pipe break, but unless we open the roadway and look, we’re not necessarily going to know.”
Cutler said state Transportation was aware the roadway was sinking in the repaired area during the last few months and had been monitoring the situation.
State workers patched the crosswalk on the south side of the intersection at First and Lincoln twice, the last time just a matter of days ago, Cutler said.
“This was not a total surprise,” Cutler said. “We knew something was happening.”
The fix will cost about $5,000, Russell said.
Cutler said the city may pay some of the cost for repairs.
“I told them if it was found that the city infrastructure contributed to the failure, we would enter into a dialogue with them concerning cost-sharing,” Cutler said.
Senior Staff Writer Paul Gottlieb can be reached at 360-452-2345, ext. 5060, or at paul.gottlieb@peninsuladailynews.com.

