An off-ramp built in the wrong place – an engineering mistake attributed to human error –on the State Route 16 construction project in Tacoma will cost the state $890,000 to correct.
“This is a dark day,” Kevin Dayton, administrator for the state Department of Transportation’s Olympic Region, said by phone Saturday.
“The first question is, ‘Gosh, how could you make such a blunder,’” Dayton said.
The problem was with the eastbound Highway 16 off-ramp to Sprague Avenue, which was in the wrong spot to line up with future work, Dayton said. The earthen off-ramp connects Highway 16 with the elevated bridge that leads to Sprague Avenue in Nalley Valley. As the project was refined from two eastbound lanes to three eastbound lanes to accommodate traffic, engineers needed to move the placement of the off-ramp to make room. But that wasn’t communicated between members of the eastbound design team and the westbound design team. Bottom line, the engineering plan went out with the off-ramp in the wrong spot.
“The contractor did exactly what was in the plan,” Dayton said.
Dayton attributed the mistake to human error within the DOT engineering group, but said the blame rests with him.
“Ultimately, it’s my responsibility,” Dayton said. “The buck stops with me. ”
The mistake was caught in October when the off-ramp was 90 percent completed, Dayton said. Engineers spent the winter redesigning. Last week, the pavement was torn up. Money in a contingency fund will cover the $890,000 to remove pavement, lower the grade up to 12 feet and rebuild the off-ramp, he said.
Correcting the error won’t extend the completion date of the project, Dayton said. Work on westbound State Route 16 is expected to finish in midsummer 2011. After that, work will begin on the eastbound lanes of State Route 16.
Dayton said no disciplinary action will be taken, but he also said he’s asked for several checks and balances to make sure it doesn’t happen again.
“Mistakes do get made in engineering and construction,” Dayton said. “We generally catch it in the field. … The big embarrassment is it got built. That seldom, if ever, happens.”
He said it’s the first time in his 27-year career that an engineering mistake was built and had to be torn out.
“Luckily we caught it at 90 percent,” Dayton said. “I wish we caught it at 0 percent.”