Current Design Work
The preliminary design work for the Initial Phase includes traffic analysis for Federal Highway Administration (FHWA) approval, continued geometric design, coordination with local and state agencies, and strategy development for delivering elements of the project with current and future funding.
Right of Way Acquisition
Project management and real estate staff have been acquiring the $15 million in right-of-way funded through the Nickel Funding Package in July 2003, with the entire $15 million committed as of June 2005. This effort has included:
- Acquiring select properties along the west side of I-5, between SR 516 and approximately S. 212th St.;
- Acquiring portions of land required from the Port of Seattle through a cooperative land trade agreement;
- Acquiring limited parcels where the threat of imminent development exists;
- Acquiring parcels qualifying as hardship acquisitions.
With the receipt of an additional $24 million in right of way acquisition funds as part of the 2005 Transportation Partnership Account, project management and real estate staff have developed an acquisition strategy that includes:
- Acquisition of many of the parcels within the northern-most segment of the SR 509 corridor, between S. 200th St. and S. 176th St.
- Continued efforts to acquire portions of land required from the Port of Seattle through a cooperative land trade agreement;
- Acquisition of parcels where the threat of imminent development exists;
- Acquisition of parcels qualifying as hardship acquisitions.
If you have questions regarding the status of your property, or whether or not your property is affected by the project, please contact Andrew Lau, the project Real Estate Manager.
Value Engineering Studies
A Value Engineering (VE) Study was conducted in November 2004 to evaluate the $94 million in new bridges and walls within the SR 509 Corridor portion of the project. The goals of this study were to:
- Review constructability impacts;
- Validate the design work that had been done to date for the bridges and structures;
- Identify potential flaws;
- Identify risks and opportunities related to structures and provide input to the project team;
- Identify opportunities for further aesthetic enhancements (related to the SR 509 Visual Guidelines).
After evaluation of the VE team proposals, the design team identified potential cost savings in the range of $10 million to $15 million. Given the baseline SR 509 Corridor structures cost of $94,350,000, the cost savings related to the VE team’s efforts over four days amount to a cost savings of approximately 10% to 15%. The majority of the savings identified related to proposals to use pre-cast structure elements in place of cast-in-place elements, with the requirement that they meet the aesthetic standards established in the SR 509 Visual Guidelines.
Environmental Mitigation
Des Moines Creek Basin Plan (DCBP) - Because of the size, nature, and location of the Des Moines Creek drainage basin, WSDOT has partnered with King County Department of Natural Resources, the Cities of SeaTac and Des Moines, and the Port of Seattle in a suite of basin improvement projects that will enhance and restore some of the critical functions of Des Moines Creek that have been degraded over years of development within the basin. Overall the basin plan consists of multiple projects aimed at specific improvements to water quality and stream health. The basin plan will help to restore the health of the Des Moines Creek Basin and reduce the storm water detention requirements for the SR 509 Project.
The current SR 509 Project Nickel Funding includes $9.0 million towards construction of the DCBP, with initial funds going to the construction of the first phase of the Regional Detention Facility, which began in August of 2004 and was completed in Spring 2005.
The second phase of SR 509 funds is currently being applied towards the Marine View Drive bridge replacement project. This project within the DCBP will remove a major fish passage barrier along Des Moines Creek, and restore and enhance the steam bed and banks within the immediate vicinity. Construction activities for the bridge replacement began in May 2005. WSDOT was also a funding partner for the preliminary design efforts for the DCBP, and has assisted in coordinating project level details involving the basin plan regional detention facilities and the design of the SR 509 extension, including project stream mitigation efforts within the basin. Based on current funding, the SR 509 project will be one of the primary contributors in funding the construction of the remaining DCBP projects. View the current graphic of the proposed DCBP projects.
Construction Partnerships
In addition to the Des Moines Creek Basin projects described above, the SR 509 Project has partnered with the City of SeaTac on their International Boulevard (SR 99) Phase 4 Project. This project improves the section of SR 99 between S. 200th St. and S. 216th St. by adding landscaped median and a third southbound HOV lane. The project also includes a new enclosed storm system, curb, gutter and sidewalk with street trees and a new traffic signal installed at South 204th Street.
The roughly $1M contribution from SR 509 is being used to raise a section of SR 99 in the vicinity of S. 208th St. up to 3 feet higher than initially designed, in order to minimize future public disruption and reconstruction costs related to building the SR 509 extension which crosses beneath SR 99. The projects construction is complete, with more information available at the City of SeaTac website.