Site work and paving for a road / highway in Des Moines, Washington. Completed plans call for site work for a road / highway; and for paving for a road / highway.

As of October 8, 2024, a general contractor has been awarded but a construction start date has not been set. WSDOT will build the remaining two miles of new SR 509 Expressway, reconfigure SR 509 interchanges at South 188th and South 160th Streets and add a southbound auxiliary lane on I-5 between SR 516 and South 272nd Street. A federally funded project with condition of award disadvantaged business enterprise goals to be determined. WSDOT - SR 509 24th Avenue South to South 188th Street New Expressway The estimated range for the Contract cost is approximately 400,000,000 to $500,000,000 The SR 509, 24th Avenue South to South 188th Street-New Expressway Project includes constructing: o A new four-lane expressway between 24th Avenue South and South 188th Street/Des Moines Memorial Drive o Reconfigured SR 509 interchanges at South 160th Street and South 188th Street/Des Moines Memorial Drive o Five new bridges o New southbound auxiliary lane on I-5 between the SR 516 interchange and South 272nd Street o Two new noise walls near South 160th Street and extension of one existing noise wall alongside I-5 o Retaining walls to minimize impacts to nearby wetlands and stream buffers o Wetland preservation enhancement and environmental rehabilitation activities at Barnes Creek and within the SR 509 corridor Deadline for Submitting RFQ Questions April 17, 2023 Questions and requests for clarification regarding this RFQ shall be submitted in writing to the WSDOT Technical Point of Contact. The following Project scope is provided to Submitters to assist in developing a team with the expertise that is required for the Project. The Design-Builder shall be responsible for management, design, and construction of the Project. The design and construction by the Design-Builder shall be in accordance with WSDOT's guidelines and standards as required by the RFP. WSDOT's intent is to allow flexibility in design and construction to accommodate processes, procedures, and innovative techniques that are preferred by the Design-Builder, as long as they are consistent with Site conditions, good engineering practices, context sensitive solutions, environmental documents and permits, other standards, guidelines, and procedures identified in the RFP, and the Project goals. The scope of Work presented in this RFQ for the Project may or may not be the final scope of Work presented in the RFP for the Project. The Project improvements shall include, but are not limited to, the following: State Route (SR) 509 o Construct a new four-lane (two-lane in each direction) expressway between the 24th Avenue S. interchange and the S. 188th Street/Des Moines Memorial Drive 8 (DMMD) interchange. 9 o Construct four new bridges. o Reconstruct the existing S. 188th Street/DMMD interchange. o Add new ramps to/from the south. o Modify two ramps to/from the north. o Modify ramp terminal intersections into roundabouts. o Add a new bridge over S. 188th Street/DMMD. o Reconstruct the existing S. 160th Street interchange. o Modify four ramps. o Modify ramp terminal intersections into roundabouts. o Modify the S. 160th Street bridge over SR 509. o Construct two new noise walls. o Restripe the existing 24th Avenue S. interchange ramps. I-5 o Construct a new southbound auxiliary lane between the S. 272nd Street interchange and the SR 516 interchange. o Construct a new culvert for the McSorley Creek crossing. o Extend an existing noise wall along northbound I-5. Other o Construct Barnes Creek Mitigation Site o Construct retaining walls o Complete building demolition o Construct stormwater conveyance and treatment facilities o Construct Highline Water District (HWD) facilities o Construct electrical services, illumination systems, traffic signals, Intelligent Transportation Systems (ITS), and signing Ali Amiri, PE Email: amiria@wsdot.wa.gov