Divers have been in the water inspecting the cable since this was first discovered Tuesday and the WSDOT says it is absolutely safe to drive on.
Three years ago, 30 cables on I-90 and 520 spans were replaced because they were showing signs of age. The Problem Solvers found, and WSDOT confirms, that the severed cable was one of the new ones, which showed no wear as of April.
WSDOT said that on Tuesday, a maintenance worker inside the western-most pontoon discovered "obvious" damage to one of the anchor cables. Since then, divers have discovered the cable suffered a hard impact, breaking it in two approximately 20 feet below the waterline.
The DOT says it hasn't identified how the cable was broken or who's responsible, though Kiewit Construction has been operating barges and tugs and working on pontoons nearby for the new 520 bridge.
Sources tell the Problem Solvers the only times they can remember cables breaking are during the 1993 Inauguration Day Storm, and when a portion of the I-90 bridge sank in 1990 after a contractor doing repairs left big openings in one pontoon during heavy rains.
WSDOT adds that with just one broken cable, the bridge is absolutely safe to drive on. Inspections show no damage from any cable whiplash to the pontoons, and with no windstorms predicted over the next several days they don't anticipate any problems.
WSDOT also says whoever is ultimately found responsible for the cable break will pay for the repair.