Heavier vehicles on the Puyallup River bridge linking Fife and Tacoma will soon have to take another route over the river.
Beginning next month, all vehicles weighing more than 10 tons will take a detour, including most emergency vehicles, tractor-trailers, school buses and Pierce Transit buses.
The bridge links Puyallup Avenue in the west to Pacific Highway to the east, and sees about 400 daily trips by semitrailers, buses and emergency vehicles, said Tacoma Public Works director Kurtis Kingsolver. Weight restrictions could be in place within two weeks.
“We know this is a significant inconvenience to a lot of people,” Kingsolver said.
The Puyallup River bridge was completed in 1927 — the same year the last Ford Model T rolled off of the assembly line.
Weight restrictions have been in place since 2009, said Dan Soderlind, project engineer for the city. But to date those restrictions allowed mass transit and tractor-trailers with an empty load, he said.
A bridge inspection performed earlier this year revealed significant wearing of the bridge’s gusset plates — critical infrastructure that joins the bridge’s structural members together to allow the bridge to hold the weight of the deck and traffic.
“Gusset plates are weak link,” the most recent bridge inspection states. Corrosion and rust have eroded gusset plates to the width of a “knife edge,” and many also have holes. Continuing to allow heavy traffic across the bridge could weaken or crack the gusset plates further, the report states.
The failure of a poorly designed gusset plate was what caused the 2007 collapse of an interstate bridge in Minneapolis during rush hour, killing 13 people. Kingsolver said the Puyallup bridge is safe to cross for lighter vehicles.
Pierce Transit expects to eliminate five stops near the bridge to allow buses to take a path around it, said spokeswoman Carol Mitchell. The rerouting could also cause a minimum seven- to 10-minute delay for routes 500 and 501, both of which cross the bridge, she said.
Tacoma Public Schools has “about six routes” that cross the bridge, said spokeswoman Elle Warmuth in an email. But the district doesn’t expect the necessary detours to cost any time or money, she said.
The Puyallup River bridge is considered “structurally deficient” under the National Bridge Inventory criteria. The bridge has a sufficiency rating of 17.6 out of 100 — worse than 99.3 percent of all bridges in the state, according to the inventory.
The bridge is also listed as “fracture critical,” which means an ill-placed strike at a specific point could cause the entire structure to collapse. The recent inspection noted that high loads have struck the overhead structure of the bridge many times.
Tacoma officials hope to one day replace the entire bridge, but only have enough money right now to fix two of the six spans adjacent to Portland Avenue on the Tacoma side. The city has $38 million in grant money it has accumulated since 2004 to do the work, but must first get permission to access the land from the Puyallup Tribe of Indians.
The area is sensitive because of its historic significance in the fish wars of the 1960s and 1970s, said Puyallup spokesman John Weymer.
At that time, tribal members statewide staged “fish-ins” to assert the right to fish in their “usual and accustomed places” per the treaties of 1855. Federal District Court Judge George Boldt ruled in 1974 that the tribes were entitled to half of the catch, a decision that was later upheld by the U.S. Supreme Court.
“We think the city does understand the sensitivity,” Weymer said. “We want to work with the city on that project and make sure it meets the standards of the Tribe, like water quality and proper use of the land.”
The city is considering a cable-stayed bridge design, similar to that of the state Route 509 bridge, he said. Kingsolver said ideally construction would begin within a year.
But replacement of the two spans alone will not shore up the bridge enough to allow all traffic, Kingsolver said. It would cost $150 million to replace the entire bridge, money the city of Tacoma doesn’t have right now.
“This is really a nationwide issue,” Kingsolver said. “The bridge infrastructure nationwide is not in great condition. It’s really expensive to replace a bridge.”Kate Martin: 253-597-8542 firstname.lastname@example.org @KateReports