Eastside history: I-405 radically altered life east of the lake

The biggest man-made object on the Eastside was just a line on a map 50 years ago.

At more than 30 miles long and made of millions of tons of concrete and asphalt, Interstate 405 dwarfs any other feature along the eastern edge of Lake Washington.

Transportation was, and perhaps still is, the determining factor in how the Eastside developed, and I-405's impact was instrumental. The freeway radically changed life east of the lake, much like the Lake Washington Floating Bridge did after its completion in 1940.

When I-405 was conceived, much of the area east of Lake Washington was a rural farming area, where Kirkland was the biggest city. The coming of a new highway could scarcely have been of more interest.

A story in the Kirkland weekly newspaper reported that the road would destroy some 50 homes in the city, including such historic residences as the John A. Andreen home built in 1899.

"Inside the home are many pieces of furniture over 100 years old and are still being used by Ellen Andreen, who was born here on Rose Hill in 1893," it stated. "She still cooks on a woodstove ... the land where Lake Washington High School now stands was once part of their homestead and for years she hiked on the many trails of this area before there were roads."

First planned in 1948

It was March 8, 1948, when the Washington state director of highways ordered a new roadway built on the Eastside to provide a speedy bypass around congested Seattle traffic.

It took until 1952 to get the plan approved and purchase access rights. A two-lane roadway was built along part of the route, with plans to expand it someday to four lanes.

But in 1956, President Eisenhower approved what was officially called the Federal-Aid Highway Act of 1956, directing that a national defense and interstate-highway system should be developed — and the future route of I-405 was included.

The resulting interstate system stretches 46,380 miles and took 40 years to build — the biggest public-works project in history.

By November the first part of the new Eastside road — known as Highway 2-A — was done, leading to amazed observations by longtime residents that it was now possible to drive from Kirkland to Bellevue in only four minutes.

But by 1960, Wes Bogart, state highway administrator, was already predicting that the roadway would "someday" have to be made six lanes wide. Just four years later, another highway official said the widening would have to take place within three to four years, because "traffic has increased at a terrific rate."

Alternate routes

The new roadway's effects on the Eastside could have been much different. An alternative route was under consideration as late as 1961.

On Aug. 1, 1961, citizens crowded into the auditorium of W.A. Anderson Junior High School in Bothell to learn about four possible routes for the new highway. One, known as the "Wayne route," would have passed along the east edge of the Valhalla housing development and the Wayne Golf Course in Bothell, with much discussion centering on a "Wayne Interchange" that would have put a cloverleaf intersection at Bothell Way.

Eventually, a route through the North Creek Valley was picked, between Bothell and Woodinville, leading eventually to multilevel intersections and dense industrial development there, and even a new University of Washington campus. The Wayne Golf Course and Valhalla remain untouched.

By 1963, work was moving rapidly, with connections made at the intersection of what was then called Primary State Highway No. 1, now known as Highway 520.

But it was already clear that the roadway, planned to handle traffic for 20 years, would not be adequate for long. By 1967, the state was scouting for a parallel route for I-405, with a map showing an additional proposed freeway running through Maple Valley, Newcastle and Lake Hills before connecting to Highway 520 at Bridle Trails.

Studies continue today about whether to build such a route, commonly known as Interstate 605, with latest concepts placing it somewhere east of the Sammamish Plateau.

Conditions swiftly changed

Year by year, I-405, and the conditions it operated in changed along with it. In 1960, it was carrying 5,300 vehicles a day; the present count at the intersection with Highway 520 is nearly 40 times that number — more than 200,000 vehicles daily.

Within a few years after it was opened, the carefully designed 405-520 interchange had become one of the trickiest and most congested in the region, and by the 1990s it had to be rebuilt. A new flyover ramp leading traffic from 520 onto northbound 405 opened in 1993.

And while it was an engineering accomplishment when it opened in 1965, a section of elevated I-405 through Renton, known as the "S curves" because of its shape, required rebuilding in the 1980s and 1990s. The new section was finished in 1995 after 22 homes were removed.

I-405 also was affected by an abbreviation no one had thought of in the 1960s: HOV. Plans for high-occupancy-vehicle lanes began appearing in 1983, when the state Department of Transportation announced it would take five to seven years to build 15 miles of HOV lanes from Southcenter to Interstate 5.

In 2002, the final sections from Bothell to Lynnwood were finished. I-405 now has some 33 miles of HOV lanes, making it possible to drive from its south junction with I-5 at Tukwila to its north junction at Lynnwood without having to leave the car-pool lanes.

Expansion plans

Plans to expand the roadway capacity have been nearly constant since I-405 was started. An I-405 Corridor Program study involving dozens of government agencies recommended a combination of mass-transit improvements and adding two general lanes for cars along the entire length of the highway route from Tukwila to Lynnwood.

As far as is known, no one has added up the costs of all the projects involved in building the freeway since 1948. Rebuilding the 405/520 interchange alone was estimated at $28 million, and redoing the S curves at $55 million.

The latest estimates for the cost of adding as many as two lanes in each direction are $9.1 billion to $10.9 billion.

Sources include Washington State Department of Transportation, Washington State Archives and The East Side Journal.