Dispute over 520 design: neighborhood vs. nature?

Early last year, two guys from Montlake hatched an idea to save their neighborhood from a huge replacement interchange the state was proposing at Highway 520.

Rob Wilkinson and Jonathan Dubman envisioned an east-west suspension bridge soaring over Portage Bay and Montlake. The interchange would move east to Foster Island, then reconnect to an exit bridge that would extend to the northwest, depositing traffic at Husky Stadium.

To their surprise, the state's transportation bureaucracy listened.

One year later, a version of their concept has emerged as the political frontrunner in plans to replace the 43-year-old highway.

The idea of a suspension bridge was scrapped, but the exit bridge was kept. A "Pacific Interchange" would be built offshore next to Foster Island, with the aerial spur to the stadium at Northeast Pacific Street.

The idea of a huge interchange — with up to 15 highway and access lanes — being built above wetlands and two islands has provoked some outrage.

But the Seattle City Council is leaning toward endorsing the plan this month, along with a six-lane floating bridge. Gov. Christine Gregoire expects to choose a bridge plan by early 2007, in time for a regional transportation ballot measure next fall.

A consensus for the Pacific Interchange would end a long stalemate over how to thread a concrete roadway, and more than 115,000 cars a day, through green spaces and homes.

"We were close to lawyering up, spending millions of dollars, and angst, not to get anywhere," said Dubman, a former software consultant who now spends his time being an advocate for the Pacific Interchange. "I don't think this project would have a ghost of a chance to get funded if it was the [Montlake] alternative."

There's no strategy yet to pay for the $4.4 billion to $5.3 billion project.

Of course, there are questions about the Pacific Interchange:

Will transportation improvements justify a large structure mingling with ducks, turtles and canoes? Or will the backlash against a wetland interchange send everyone back to the drawing board?

Councilwoman Sally Clark says decisions made long ago to place the highway in a recreational and residential location have left the city in a bind. The Pacific Interchange seems the best among flawed options, she says: "It's an angst-ridden, everybody-doesn't-feel-good, possible slam-dunk."

New scenery

Extending south from the proposed interchange is a green peninsula, a former city landfill now owned by the state Department of Transportation, that attracts picnickers, hackysackers, Frisbee-catching dogs, and sunbathers. Wilkinson and Dubman say they're among many who have trespassed onto an abandoned highway ramp to take the 43-foot leap into the lagoon.

Information

More 520 commentary on the Web

Washington State Department of Transportation: www.wsdot.wa.gov/projects/sr520bridge

Pacific Interchange supporters: www.betterbridge.org

Anti-expansion coalition: www.noexpansionofSR520.org

UW Arboretum and Botanical Garden Committee: depts.washington.edu/wpa/abgc/

It's here that a new interchange would actually improve the scenery, they say.

After the state removes some half-built ramps from a canceled 1960s project, it would also relocate some active ramps to the new interchange, instead of leaving them spread across a broad area.

The new high-rise design would let in more daylight than the existing bridge, which is barely an oar's length above the lake, Dubman said, an opinion the state shares.

The existing Montlake Interchange would be dismantled. In its place, a landscaped lid would cover the six-lane highway just east of Montlake Boulevard. The lid would be connected to adjoining parks. By contrast, adding lanes to the existing interchange would remove 3 ½ acres of parkland.

The state has warmed to the Pacific Interchange because it would offer the most improvement in travel times. Cars heading to the University of Washington would bypass the narrow, four-lane Montlake Bridge. Also by moving the exit farther east to the Pacific Interchange, there would be less chance that eastbound traffic on 520 would back up all the way to Interstate 5.

City Councilwoman Jan Drago said she intends to vote for the Pacific Interchange because it's the only option that would carry bus-rapid transit riders directly to the UW.

Montlake Boulevard Northeast would be widened to six lanes, to unclog traffic north of the stadium.

Passing through wetlands

Highway 520 bisects the University of Washington Botanic Gardens, encompassing grasslands, tree nurseries and the Washington Park Arboretum.

Some 200 species of birds fly by, and some coyotes recently stopped an infestation of nutria. The continent's best collection of maples and second-best collection of hollies are in the Arboretum, says gardens director David Mabberley.

The marshes and the former landfill are fine examples of UW's leadership in environmental restoration, he said.

"What they propose, in effect, is to add a cross over it. We'd be the only botanic gardens in the world to have an interchange in the middle."

A Pacific Interchange would take 2.3 acres from the arboretum, and additional wetlands would be disturbed as roadway columns are built.

The UW Faculty Senate has challenged the proposal on environmental and other grounds. And the Seattle Audubon last week urged the state to drop it, in part because the overpass bridge would encroach on habitat for the great blue heron at Marsh Island.

Mabberley said naturalists from overseas have written to object. "This is not a local issue," he said.

He urges the state to study a submerged tunnel, an idea the DOT previously rejected because it requires costly underwater interchanges.

To reduce the environmental problems, Virginia Gunby, a former state transportation commissioner, suggests a new four-lane bridge, with two of those lanes limited to transit and carpools in peak hours. A four-lane bridge would not require a larger interchange.

The environmental controversies over replacing 520 have been less emotional on the Eastside. There, the state has proposed building three landscaped lids over the highway as well as noise walls. A possible 6 ½ acres of wetlands would be filled in by construction, and the state would create or improve more wetlands elsewhere.

A narrower option

In search of a better political and physical fit, the state is trying to narrow the Pacific Interchange's widest point from its earlier 425 feet, to 295 feet. That would require slimmer safety shoulders, narrower road lanes, and sharp right turns for drivers (instead of curved ramps that flare out), with less space for daylight between the aerial ramps.

The proposed 110-foot-high exit bridge to UW — which would pass over the boaters' entrance to Montlake Cut — might be negotiated down to 70 feet to save mountain views, if the Coast Guard agrees.

Either way, views at lake level would be forever changed.

Wilkinson, a professional photographer who cruises in his classic 1941 Chris-Craft, hopes this will be the setting for architect Santiago Calatrava (famous, in part, for his work on bridges) or some other inspired soul to create a landmark.

"Seattle has had bad karma as far as bridge designs go," he said. "Why can't we have at least one beautiful structure?"

Opponents sometimes accuse Montlake boosters of offshoring their highway problems to a nature refuge.

It's a critique Dubman calls unfair: "It's a complete myth Montlake is making its neighborhood wonderful, at the expense of everyone else. Montlake is going to get eight years of construction."

Mike Lindblom: 206-515-5631 or mlindblom@seattletimes.com