ONALASKA – Drivers on State Route 508 will notice a change Wednesday, July 17, when the Washington State Department of Transportation installs stop signs on both sides of the South Fork Newaukum River Bridge.
A year ago, officials restricted vehicles weighing more than 7 tons from crossing the 83-year-old, steel-truss bridge. WSDOT enacted the restriction after routine inspections determined the structure was weakening from severe corrosion.
Despite multiple restriction signs posted along SR 508, some travelers continue driving heavy vehicles across the bridge. The new signs aim to prevent further violations and potential damage to the aging bridge.
“Forcing drivers to stop before crossing the bridge gives them a last chance to read the signs and, if their vehicles are too heavy, take a reasonable alternate route,” said Chad Hancock, WSDOT Southwest Region traffic engineer.
WSDOT will install stop signs along SR 508 at Centralia-Alpha and Cinebar roads. Electronic message boards will alert drivers for one week after the change.
In an effort to give drivers enough advanced warning to adjust travel plans if necessary, WSDOT is also installing additional weight-restriction signs, some as far away as Morton.
“This really is our opportunity to keep the bridge open,” said Hancock. “If we can’t keep drivers from violating the weight restriction, we could be looking at full closure until it can be replaced.”
WSDOT will continue to monitor traffic on the bridge using a portable camera and traffic tubes. Traffic tubes record vehicle types by measuring the number of axles on each vehicle. For accuracy, the tubes are calibrated for the existing speed limit.
The SR 508 South Fork Newaukum River Bridge was built in 1930. It is inspected at least once a month and is third in line for replacement on WSDOT’s statewide bridge priority list. The earliest construction could begin is 2018, depending on available funding.