Evergreen Point Floating Bridge

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Evergreen Point Floating Bridge

The Governor Albert D. Rosellini Bridge—Evergreen Point (formerly the Evergreen Point Floating Bridge, and commonly called the SR 520 Bridge or 520 Bridge) is the longest floating bridge on Earth at 2,285 metres (7,497 ft) and carries State Route 520 across Lake Washington from Seattle to Medina.

The Evergreen Point of the bridge's original name is the westernmost of the three small Eastside peninsulas that SR-520 crosses. (The other two are Hunts Point and Yarrow Point.) In 1988, it was renamed for Rosellini, who had advocated its construction.


The bridge was opened for commuter traffic on August 28, 1963 after three years of construction. It was built as a four-lane toll bridge to provide easy access from Seattle to Eastside communities such as Bellevue, Kirkland, and Redmond. The total cost of the bridge, in 1961 dollars, was $21 million ($153 million in 2011 dollars). To make up for this cost, commuters paid a 35-cent toll in each direction until 1979. The toll booths were converted into bus stops.

The bridge impacted many communities on the Eastside. Redmond's population saw a dramatic increase, jumping from less than 1,500 in 1960 to 11,000 in 1970. It was the second floating bridge to cross Lake Washington; the first was the Lake Washington Floating Bridge, built in 1940 as part of U.S. Route 10, later part of Interstate 90, which at its construction was the largest floating structure ever built.

In 1989, an electrical fault caused the drawspan to open during rush hour, causing one death and five injuries. In 2000, a gravel barge struck the bridge, closing it for eleven days and causing $500,000 worth of damage.

Future replacement

Today the bridge is near the end of its useful life, according to the state Department of Transportation. In 1997, Myint Lwin, WSDOT's chief bridge engineer at that time, said that even with repairs, the bridge could be expected to last only about twenty more years (until 2017). The bridge must be closed in high winds, and even after a seismic retrofit in 1999, it is at risk of collapse in an earthquake. Because of the weight of various reinforcements over the years, the bridge currently rides about 1 foot (30 cm) lower in the water than it did originally. The DOT is working on replacing the aging bridge with a new span of six lanes.

The bridge is anchored by a large number of high-strength cables. According to an interview conducted by local newspapers, a severe storm during the bridge's lifespan came within strands of breaking some of these cables, which would have resulted in the catastrophic collapse of the bridge. Since then, additional cables have been added, and much of the bridge has been replaced with lighter materials, but the danger remains. The bridge was originally designed to stand up to a 100-year storm, but the assumptions used actually reflected what is now considered to be a 20-year storm for the Seattle area.

Just five years after the bridge opened, a study commissioned by the state legislature was completed to figure out how to provide for the great demand for cross-lake transportation. That study evaluated bridge and tunnel crossings north and south of the bridge. To help provide the political lubrication needed for any plan to go forward, the Trans-Lake Study was commissioned by the State of Washington. The study brought together 47 representatives of public agencies, neighborhoods, businesses, and advocacy interests. Ten years later, the problems have not been solved. WSDOT is proceeding with plans to build the bridge replacement, with an opening in 2014. To fund these improvements, in May 2009, Gov. Gregoire signed ESHB 2211, which authorizes tolling on the SR 520 bridge beginning in 2010. The intent of tolling the SR 520 bridge is to allow WSDOT to secure revenue in order to begin pontoon construction in 2010, which is critical to replacing the SR 520 bridge by 2014. Tolling is expected to start in summer 2011. The State Transportation Commission has proposed a toll of US$3.50 each way during peak periods. The proposed rates during other hours are to range from $0 to $2.80. Many groups continue to fight the project, even as it steadily moves toward construction.


In December 2011, tolling will start on the SR 520 floating bridge. The revenue generated from the tolls will help pay for the replacement bridge. All tolling will be done automatically with no tollbooths. Tolling for people without Good to Go passes will be done by license plates. Toll readers will be placed on gantries at the east highrise.

Toll rates for two-axle vehicles (includes motorcycles). Multi-axle vehicles will pay a higher rate.


The bridge carries 115,000 vehicles per day but was only designed to carry 65,000. Because of this bottleneck, commuters often follow the motto "anything but the 520 bridge" during peak traffic, with I-90 or even a northbound loop around the lake via Bothell and Kenmore preferred as alternate routes.

Because Microsoft, one of the area's largest employers, is on the Eastside just off 520, traffic on the bridge tends to be heaviest west-to-east (away from Seattle) in the morning and east-to-west (toward Seattle) in the evening, opposite from what one might expect, a so-called "reverse commute". (The I-90 floating bridge has more typical traffic patterns, with commuters going into Seattle in the morning and returning east in the evening.) Commuters often use this knowledge to take the bridge with the least traffic for their desired trip at various times of day. Electronic signs on I-405 display estimated times to Seattle for both 520 and I-90 routes. Commuters jest about the traffic bottleneck that is created around the 520 bridge and Interstate 405, nicknaming it "The Kirkland Crawl" as it becomes parking lot traffic during peak rush hour, around the city of Kirkland where 520 (coming from Redmond and Microsoft) and 405 (south from Everett and Boeing) meet.

Scenery visible westbound on clear days include the Olympic Mountains and Husky Stadium on the University of Washington campus, as well as two metal sculptures. Eastbound are expensive waterfront homes in Medina, including the large home of Bill Gates on the southern side, which is extensively lit during the holiday season.

On clear days, Mount Baker is visible to the north, the Cascade Mountains are the backdrop, and Mount Rainier is to the southeast. Mercer Island is to the south. On July 4, fireworks are visible from many communities and homes along the lake.

The bridge incorporates an infrequently used drawspan to allow large vessels to pass. Smaller vessels pass under the "high rises", elevated portions of the bridge on each end. The drawspan is also opened during major storms to relieve water pressure.

Building Activity

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