Index

Surveys

DJC.COM
 
 

July 12, 2001

Bringing a city stream back to life

By DOUG SOVERN
URS Corp.

Nevada Street bridge
A series of step pools raise the water level as it passes under the Nevada Street bridge.

bridge
Photo by Mike Morse/Seattle Public Utilities
Fish skeleton bridge designed as part of the site artwork by Lorna Jordon.

before
Photo by Doug Sovern/URS Corp.
The channel under the Nevada Street bridge prior to stream improvements.

step
Photo by Mike Morse/Seattle Public Utilities
A timber step down near the Nevada Street bridge.

pedestrian bridges
Culverts over Longfellow Creek were replaced by culverts topped with pedestrian bridges.

spawning ground
Photo by Mike Morse/Seattle Public Utilities
The base flow stream narrows and deepens here to protect fish while spawning and migrating. Also provided is clean spawning gravel.

The stream rehabilitation for the Longfellow Creek Yancy Street project is an integrated planning and design project on about six acres of city-owned land between Yancy Street and Genesee Street.

The project was completed for Seattle Public Utilities on land owned by the Seattle Department of Parks and Recreation.

This project aggressively reclaimed a ruined urban stream and now provides secure, life-cycle habitat for salmonid and other aquatic species in urban open space.

The stream rehabilitation concepts were an integral part of an urban site and corridor planning that has converted a blackberry-choked stream and site to high-quality urban open space.

The “new” open space has been adopted by the neighborhood and is now filled with people.

The lower segment was completed in 1999, while the remainder of the stream rehabilitation was completed in 2000. All of the in-stream facilities have prospered from several large storm events and spawning of returning coho was successful in both 1999 and 2000.

The lower segment provided excellent rearing habitat for 1999 and 2000.

An aesthetic design is featured to encourage the public to use and feel ownership of this urban open space. Inclusion of public art increases the sense of value in the site and enhances feels of public ownership.

Future site projects will add a dragonfly pavilion and a fern amphitheater.

The riparian corridor completed in this project both supports the theme of the public art and aesthetic design, but also is the unifying feature within urban open space site.

Two bridge crossings of Longfellow Creek are specifically created in a form, which supports art and aesthetic themes.

The bridges permit controlled public access to the creek while maintaining privacy for the fish and aquatic environment. The “fish bone” bridge uses a contoured steel pipe shell and varying width and height dimensions to convey an image of a fish bone structure.

Near the future fern amphitheater located near Genesee Street, the basic structure of a sweeping pedestrian bridge was constructed. When completed in the subsequent art construction phase, the bridge will gracefully convey pedestrians over Longfellow Creek to the cozy confines of the fern amphitheater.

Project Team:

Seattle Public Utilities —
Owner, permits, design input, monitoring

URS —
Prime consultant, civil design, specifications, bidding assistance, construction monitoring

Hough Beck & Baird —
Site planning, site design, upland planting

Taylor Associates —
Fish biology, monitoring

Lorna Jordon —
Artist


Doug Sovern is a professional engineer and senior project engineer at URS Corp.


Other Stories:



Copyright ©2009 Seattle Daily Journal and DJC.COM.
Comments? Questions? Contact us.