New WSDOT rules prompted WB I-90 bridge closure

Any closure on the I-90 floating bridge is extremely rare, but that might change, at least a bit, because of news rules put in place because of light Rail construction on the bridge.

Under the rules, anytime winds from the north reach 26 miles per hour for more than two minutes and waves reach two feet in height the westbound lanes will be close. That's to protect the structure of the bridge and make last longer.

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WSDOT imposed the new rules after a Sound Transit analysis showed the pontoons on the westbound side of the bridge could be damaged by high northerly winds.

Taking a look back at the weather over the past 10 years, WSDOT says the were eight days the winds reached 26 miles per hour but only one day where waves reached two feet. The agency estimates under the new rules, the bridge would be shut down once every five to 10 years.

But the rules may not be in place that long. Sound Transit is strengthening the bridge as part of light rail construction. When that's done in the fall of this year, the WSDOT will revisit the rules and they could change again.

The new rules to do not impact eastbound traffic.

For more information, check out this blog from the WSDOT...