WSDOT and Graham Contracting have agreed to open a temporary eastbound on-ramp to replace the arboretum on-ramp prior to closing the State Route 520 West Approach  Bridge South for replacement. Vehicles will cross over the structure and connected to the West Approach Bridge North, which will change from westbound-only lanes to two lanes in each direction.
WSDOT and Graham Contracting have agreed to open a temporary eastbound on-ramp to replace the arboretum on-ramp prior to closing the State Route 520 West Approach Bridge South for replacement. Vehicles will cross over the structure and connected to the West Approach Bridge North, which will change from westbound-only lanes to two lanes in each direction.
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.