Not all residents on Lake Washington Boulevard or in Madison Park think a temporary on-ramp to eastbound State Route 520 will help ease traffic through the Washington Park Arboretum after the existing arboretum on-ramp closes this fall.

The Washington State Department of Transportation plans to open a temporary on-ramp to temporary eastbound lanes on SR-520 when they close the existing arboretum on-ramp to begin replacing the West Approach Bridge South. The temporary on-ramp will be northwest of the existing arboretum ramp, on Lake Washington Boulevard, looping over the bridge. The arboretum on-ramp can then be used by crews to access the West Approach Bridge South.

“Right now, there are three westbound lanes coming west to Seattle,” said WSDOT spokesperson Steve Peer. “To accommodate the temporary shift in eastbound traffic, they’ll be cut down to two lanes until new eastbound lanes are built.”

When that work is finished, the temporary on-ramp will close. That’s because the temporary ramp is located at the same site as a planned new pedestrian and bicycle bridge over SR-520. During those two years, WSDOT’s contractor plans to improve traffic flow on Montlake Boulevard approaching its eastbound on-ramp.

WSDOT contends the temporary ramp would still provide direct access to SR-520 from the Montlake and Madison Park neighborhoods “while minimizing impacts to mobility and operations” during construction.

Madison Park resident Richard Weil said closing the temporary ramp after two years and routing traffic west to Montlake “is not going to do squat” to reduce traffic through the arboretum.

“Why don’t they leave it open permanently?” he asked. “They seem to be able to rebuild to match height differences on other projects. None of this is well thought out in terms of Montlake.”

He made his remarks at WSDOT’s June 6 open house on the project. More than a dozen WSDOT officials strolled through the meeting room at St. Demetrius Greek Orthodox Church, pointing to easel charts and answering questions.

A chart about the proposal states WSDOT “heard strong support for removing the ramp during a ‘robust’ planning and public involvement process.”

But not from Weil.

He predicts that once the temporary ramp is closed, cars will still be sitting, stuck in traffic further south in the arboretum due to backups approaching the Montlake intersection.

Weil drives through the arboretum to get from Madison Park to the University Village shopping center

“I hear a lot of excuses, but I don’t see how it improves anything,” he said. “It’s already taken me up to 45 minutes to get home from the U-Village.

John Carter, who lives on Lake Washington Boulevard, also said funneling traffic to the Montlake on-ramp after closing the existing arboretum on-ramp won’t cut traffic through the arboretum, except along the soon-to-be-closed on-ramp.

“Instead of accessing 520 directly, traffic will have a convoluted route past all of those houses [on the boulevard],” he said. “Will cars be turning left from Lake Washington [trying to go east on the bridge]?”

WSDOT said left turns won’t be permitted to access the temporary ramp. They didn’t offer details on what would be done to prevent that.

Peer said WSDOT originally planned to improve the Montlake intersection first — before closing the arboretum on-ramp. But design-build contractor, Graham Contracting, proposed opening the temporary on-ramp first.

“That way, traffic on Lake Washington won’t have to get on through Montlake for another two years,” Peer said. “The goal was to start looking at how vehicles can pass more easily, and Graham came up with the [temporary on-ramp] option. After we make the improvements on Montlake, we’ll see traffic shifting onto the new West Approach Bridge [South] structure.”

The full Montlake Project Community Construction Management Plan, which includes a project timeline, can be viewed at this shortened link: