SR 520 Online Open House – Roanoke lid

WSDOT is preparing to build a new Roanoke lid over SR 520 between 10th Avenue East on the west and Delmar Drive East on the east. The lid will reconnect the neighborhoods to the north and south of SR 520 with community open space and connections to the city of Seattle’s bicycle and pedestrian network. WSDOT developed the initial concept for the lid during the 2011-2012 Seattle Community Design Process.

The SR 520 design team has refined the previous design concept to provide new viewpoints and outlooks, improve trail connections, and create a safer north-south connection over SR 520.

The following material was discussed at this summer’s community stakeholder workshops. Much of the information reflects feedback workshop participants and visitors to the online open house provided. Please use this website’s Feedback page to send us any additional comments you may have.

Existing condition

An overhead view of SR 520 as it passes beneath 10th Avenue East and Delmar Drive East in Seattle, with trees and the roofs of homes visible to the north and south of the highway.
The current view of SR 520 as it passes beneath 10th Avenue East and Delmar Drive East.
A cross-section illustration of SR 520 in the Roanoke area of Seattle, looking west, with north Capitol Hill at left and Roanoke Park at right. The highway has two general-purpose lanes and an on-ramp or off-ramp, in both directions.
A cross-section illustration of SR 520 in the Roanoke area of Seattle, looking west.

Current design concept (2019)

An overhead plan view of a new, landscaped highway lid over SR 520, with 10th Avenue East at the lid's west end and Delmar Drive East at the east end. SR 520 runs left and right, or east-west, beneath the lid.
An overhead plan view of a new, landscaped highway lid over SR 520.
The top image is a conceptual cross-section plan view of the Roanoke lid. The cross section shows the lid sloping downward from west to east at approximately a 6 percent grade, with a flattening to about 2 percent grade in the lid’s middle. A second image shows an overhead plan view of the lid’s southern half, with about a 300-foot diameter between the lid’s central loop trail, which is noted as having about a quarter-mile circumference.
At top is a conceptual cross-section plan view of the Roanoke lid, showing an approximate 6% grade slope from west to east, with a flattening in the middle. The second image notes a 300-foot diameter for the lid’s looped trail. The trail’s circumference is about a quarter mile.
Three cross-section images of SR 520 in the Roanoke Park/Portage Bay neighborhood, all looking west. The first shows the existing conditions, with two-general purpose lanes in each direction and an on- or off-ramp. The second shows the preliminary design concepts for the Roanoke Lid from the 2015 Final Concept Design Report. This design shows a deep canyon along the south side of the lid. The third cross-section shows a refined 2019 concept for the Roanoke Lid, which removes the canyon effect and provides a more level connection between the lid and north Capitol Hill.
Above are three cross-section images of SR 520, looking west, in the Roanoke area. The baseline conceptual design from the 2015 Final Concept Design Report shows a deep canyon along the south side of the lid. The bottom cross-section shows a 2019 refined concept for the Roanoke lid, removing the canyon effect and providing a more level connection between the lid and north Capitol Hill.
Plan view of the gateway to the future Roanoke lid neighborhood open space at the southeastern corner of East Roanoke Street and 10th Avenue East. The plan includes future roadway configuration as well as paving and planting concepts on the lid.
Plan view of the gateway to the future Roanoke lid’s neighborhood open space at the southeast corner of East Roanoke Street and 10th Avenue East.
Design rendering of the gateway to the future Roanoke lid neighborhood open space at the southeastern corner of East Roanoke Street and 10th Avenue East. The rendering shows the view looking southeast with a paved entrance in the foreground and planted greenspace in the background.
Design rendering of the gateway to the future Roanoke lid neighborhood open space at the southeast corner of East Roanoke Street and 10th Avenue East, looking southeast.
Three images related to the conceptual design of the future Bagley Viewpoint along Delmar Drive East on a new Roanoke lid. The first image is a plan view showing the conceptual design of the viewpoint, with a lean rail and benches. The second image is a photograph of the large, white marker stone and plaque at the existing Bagley Viewpoint. The third image is a photograph of the bench and sitting area at the existing Bagley Viewpoint.
Three images related to a future Bagley Viewpoint on the Roanoke lid. The first image is a plan view showing the viewpoint’s conceptual design. The second image is a photo of the marker stone and plaque at the existing Bagley Viewpoint. The third image is a photo of the existing viewpoint’s bench and sitting area.
A plan view of the conceptual design of future Roanoke lid outlooks along 10th Avenue East, one on the east side of the street and one on the west side. The outlooks include paved areas, stairs and ramps, and landscaping.
A plan view of the conceptual design of future Roanoke lid outlooks along 10th Avenue East — one outlook on the east side of the street and one on the west side.
A design rendering of a new Roanoke lid's eastern outlook along 10th Avenue East. The rendering shows several people on a paved platform, looking northeast past trees and a paved trail, toward Portage Bay in the distance.
A design rendering of a new Roanoke lid’s eastern outlook along 10th Avenue East, looking northeast toward Portage Bay.
Two images related to the conceptual design of the Federal Avenue overlook at the southern end of a future Roanoke lid. The first image is conceptual plan design of the overlook, including paved areas, stairs and ramps, and landscaping. The second image is an example photograph of an informal stone staircase in a park, with a man walking up the stone steps.
A conceptual plan design of an overlook on a future Roanoke lid’s southern end,
along the north end of Federal Avenue. The accompanying photo
is an example of a stone stairway.
A conceptual design rendering of the Federal Avenue overlook, with people standing and sitting at the stone-paved overlook in the foreground, looking northwest toward the landscaped Roanoke lid in the background.
A conceptual design rendering of the Federal Avenue overlook,
looking northwest across a future Roanoke lid.

Key themes: Roanoke lid open space

The information below, reflecting the feedback of workshop participants and visitors to the online open house, was shared at the Sept. 12 community stakeholder workshop.

How participants would use the Roanoke lid’s open space

  • Walking, dog walking, relaxing, throwing Frisbee
  • Scenic views

Planting character that resonates with participants

  • Balance dense plantings for privacy with more open plantings to improve sightlines and viewpoints (advanced to conceptual design)

Participants’ priorities for lid viewpoints, and why

  • 10th Avenue East viewpoints – buffered from the highway and provide access to business district (advanced to conceptual design)
  • Federal Avenue viewpoint – connects to the neighborhood and provides unique views (advanced to conceptual design)
  • Bagley viewpoint – important to incorporate its historic characteristics in new design (advanced to conceptual design)

Other discussion points

  • Provide water fountains (advanced to conceptual design)
  • Provide restrooms on the lid (explored, not feasible)
  • Interest in off-leash dog park (explored, not feasible)

Workshop #1, July 11:
Roanoke lid “look and feel”

The materials below were shared with participants at the July 11 community stakeholder workshop.

Map of the State Route 520 corridor near its interchange with Interstate 5. The map shows the location of a planned lid over the highway in the Roanoke area of Seattle, between 10th Avenue East at the lid’s western end, and Delmar Drive East at the lid’s eastern end. The map shows four viewpoints on different sides of the lid. The map also shows a new, replacement Portage Bay Bridge to the right, or east, of the lid.

Key considerations

  • General size and footprint of the lid (approximately 3 acres of open space area)
  • The lid is planned to be a passive space for unprogrammed recreational activities, such as walking, biking and taking in scenic views. The lid is not desired as a space for facilities like playgrounds and tennis courts.

Discussion questions

  • How would you use the Roanoke lid?
    • Which of the park character example resonates most with you and why?
    • What is the importance of vegetation screening compared with a more open feel?
  • The Roanoke lid provides opportunities for excellent views outside (outlooks), as well as views looking into the lid (overlooks).
    • Which would you emphasize/prioritize? How would you use the viewpoints?
    • Would you prefer larger, hardscaped, structured viewpoints or smaller, unstructured, landscaped areas as viewpoints?

Roanoke lid viewpoints

The photo at left, looking east, shows traffic travelling east and west on SR 520, with a green and yellow highway sign extending above the two eastbound lanes. A tall, concrete wall is along the right side of the eastbound lanes, with leafless trees above the wall. In the distance is water, Portage Bay, and at the top of the photo are gray skies.

The illustration to the right of the photo shows four silhouetted people on a yellow platform – two seated and two standing. Just below the platform is a green area, with a wall running along its edge. Past the wall is a highway bridge running off into the distance, with blue water on both sides. On the right side of the bridge is a path or sidewalk, with a circular ramp in the foreground.
The photo at left, looking east, shows vehicles travelling on SR 520, with trees and shadows to the left and right of the highway, the Delmar Drive East overpass in the distance, and farther in the distance, a partial view of water, with blue sky above.

The illustration, to the right of the photo, is a conceptual view of a highway lid over SR 520, looking east from 10th Avenue East. Two silhouetted people are seated on benches, and two others stand below on a stair landing. Green, grasslike areas cover the lid, with a looping trail where three silhouetted people walk in the distance. In the far distance is water.
The photo at left, looking west, shows SR 520 as it approaches Interstate 5. At the far left are tall trees next to a shadowed highway ramp with a car moving toward the bottom of the photo. To the ramp’s right is a separate single highway lane, with a car exiting a tunnel inside a small hill. To the right of the tunnel lane are two more highway lanes that head into the distance, curving to the left. Farther right is another, separate traffic lane with two cars traveling into the distance. At the right is a city street, with the large white building next to it. In the far distance, above the horizon, is blue sky.
The illustration to the right of the photo shows four silhouetted people standing on a yellowish platform, with two benches and a low gray wall directly below them. Behind the low wall is a green area, with another low wall beyond the green area. In the distance is a divided highway curving to the upper-left, and highway ramp curving to the upper-right. In the far distance is gray sky.

Roanoke lid proposed planting area

The map at left shows an overhead view of a planned lid over SR 520 in Seattle’s Roanoke neighborhood, with gray-shaded highway lanes to the right and left of the lid. The Roanoke lid is shaded yellow to signify neighborhood open space. Streets that border the lid along the north, or top, the east, or right, and the west, or left, are shaded pink to signify boulevards or avenues. Blue-shaded areas to the west, or left, south, or bottom, and east, or right, of the lid signify neighborhood and open space transitions.

To the right of the map is an image containing five separate outdoor photos. At upper-left, beneath a blue banner that says neighborhood and open space transitions, is a black and white photo with a street or lawn area in the foreground, and behind it a low, stone wall , with two small trees to the left, and larger evergreen trees to the right. In the distance are gray skies. The photo at upper-right, also beneath the blue banner, shows a mix of leaf-bearing and evergreen trees. In the middle of this image, under a yellow banner that says neighborhood open space, is a photo of a green grass-covered area, with trees and shrubs at top and to the right.  At lower-left, beneath a dark-pink banner that says boulevards and avenues, is a photo of a two-lane street, with several bicyclists riding both away from and toward the camera. Large, leaf-bearing trees line both sides of the street. At the lower-right, also beneath the dark-pink banner, is a photo of a wide, paved path, with two bicyclists riding by. Leaf-bearing trees line both sides of the path, a grassy lawn is to the right of the path, and to the left is a large body of water.

Note: Concepts and materials shown are draft ideas for discussion purposes only, and are subject to change.

Please share your feedback regarding the Roanoke Lid (e.g. urban design elements to support safe and usable neighborhood green spaces).