All drivers in the Central Puget Sound Region should be prepared for tolling on the State Route 520 bridge to start at 5 a.m. Thursday, Dec. 29.

“This change will affect more than just bridge users,” said Washington State Department of Transportation Toll Division Director Craig Stone in a press release. “It will affect drivers on Interstate 90, SR 522 around the top of Lake Washington and local on- and off-ramps to I-5, I-90, I-405 and SR 520.”

While it’s impossible to predict exactly how many drivers will use alternate routes, extensive traffic analysis shows traffic reductions on SR 520; some commuters will adjust when they travel, switch routes, use transit, share a ride or skip the trip completely.

“Drivers from Issaquah to Seattle and Tukwila to Shoreline will see changes to their commute,” Stone said. “Drivers who use these routes should prepare for potential traffic delays and adjust their schedule accordingly. We expect traffic patterns will change daily, and it will take several months before traffic settles into a predictable new pattern.”

WSDOT prepared for the start of tolling by working with local agencies potentially affected as SR 520 traffic patterns adjust to tolling. That coordination will continue as WSDOT monitors traffic flow and signal performance to determine if adjustments are appropriate.

Traffic engineers will collect daily traffic data from 34 key locations on state highways and 28 monitoring points on streets and intersections in Seattle, Bothell, Kenmore, Kirkland, Redmond and Woodinville. They will track travel times, signal coordination and traffic behavior on I-405, I-5, I-90, SR 520 and SR 522, as well as numerous ramps and local roads.

WSDOT will also provide as much data as possible to traffic reporters and the public to help drivers make informed decisions about alternate routes.

Drivers can use WSDOT’s mobile apps and traffic twitter feeds to check travel times and collision information before heading out. Follow @WSDOT, @GoodToGoWSDOT and @WSDOT_traffic on twitter. WSDOT recommends drivers use the day to download apps and bookmark information that will be helpful.

“We expect drivers will experiment and try a variety of methods to modify their commutes,” Stone said. “They may take advantage of transit, telecommute, change the time they travel or take another route. It will take some time to see what the new normal really looks like.”

How to be Good To Go!

- Purchase a Good To Go! pass, activate and install it today, before tolling starts Thursday, Dec. 29.
- Update existing account information, including credit card or bank information and vehicle license plate numbers.
- Purchase the popular $5 sticker pass at participating stores: Costco, Walgreens Safeway, Fred Meyer and QFC. Visit http://www.wsdot.wa.gov/goodtogo/retail for a list of retail locations.
- Visit a service customer service center or a mobile customer service station. Find locations and hours online at http://www.wsdot.wa.gov/GoodToGo/contacts.htm.
- Buy any of the five pass options online at http://www.wsdot.wa.gov/goodtogo - please note, may take up to five days to process and mail.

About tolling on the SR 520 bridge

Tolling on SR 520 is expected to raise $1 billion overall toward the $4.65 billion SR 520 bridge replacement and HOV program, which builds 12.8 miles of safety and mobility improvements from Interstate 5 in Seattle to SR 202 in Redmond. The existing SR 520 floating bridge opened to traffic in 1963, and is vulnerable to sinking during a severe storm after weathering decades of wind and waves. The new bridge will better withstand storms and move more people across the lake with a new transit/HOV lane for buses and carpools in each direction. The target date to open the new bridge to traffic is December 2014.