HomeMy WebLinkAboutTrans 2014-11-24 Item 2C - Update - 42nd Avenue South Phase III - South 160th Street Intersection DesignCity of Tukwila
Jim Haggerton, Mayor
INFORMATIONAL MEMORANDUM
TO: Mayor Haggerton
Transportation Committee
FROM: Bob Giberson, Public Works Director',
BY: Cyndy Knighton, Senior Program Manager
DATE: November 21, 2014
SUBJECT: 42nd Ave S Phase III (Southcenter Blvd — S 160th St)
Project No. 99410303
Intersection Improvements at 42nd Ave S and S 160th St
ISSUE
Update on proposed improvements at the 42nd Ave S and S 160th St intersection, which is a
portion of the larger 42nd Ave S Phase III Project.
BACKGROUND
Since early 2012, the City has been working on the design of the combined 42nd Ave S Phase III
Project and the Gilliam Creek Culvert Replacement Project. The design is between the 60% and
90% level of completeness. Consideration is still being given to modifying the design to include
undergrounding of the aerial utilities, which is not currently included. As the undergrounding
option is a possibility, construction of the combined projects will not occur until the 2016
construction season to allow for additional design to be completed if necessary.
DISCUSSION
A request was made to present the proposed improvements at the southernmost intersection of
the project for discussion at the Transportation Committee. The project will widen the roadway
to include sidewalks, buffer zones, and 14 -foot wide travel lanes with painted bike sharrows.
ADA accessible ramps will be included in the new sidewalks which will vary between 7 and 8
feet wide on the west side and 6 feet wide on the east side throughout the length of the larger
project.
The 42nd Ave S Phase III Project's paving will extend into the S 160th St intersection, which is
entirely located within SeaTac city limits. Walls will need to be constructed near the property
lines on the two adjacent parcels as there is significant grade difference between the roadway
and the private properties. A larger water meter owned by Water District No. 125 and the
existing utility poles will be relocated. Under the current design, a series of poles will need to be
installed to carry the weight of the lines as the ownership transfers from Seattle City Light to
Puget Sound Energy (power lines), as well as the Comcast and Centurylink communication
lines.
FINANCIAL IMPACT
None.
RECOMMENDATION
Discussion only.
Attachments: Intersection Design Graphic
W: \PW Eng1PROJECTS\A- RW & RS Projects \42nd Ave S Phase III (99410303 94 -RS03) \Design \INFO MEMO 42nd -160th Intersection TC Briefing 11 -21 -14 RRT- sb.docx
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