This is a service / maintenance or supply contract in Chehalis, Washington. Contact the soliciting agency for additional information.

Proposals are being requested from Engineering Consultants to develop scour mitigation countermeasure plans for two federally funded scour critical bridge projects in Lewis County, Washington. Lewis County (County) is pursuing design options to provide long term scour mitigation countermeasures at both sites to withstand 100-yr storm events (with evaluation for 200-yr flood events and climate change) and bring each structure's current NBI Code 113 Rating of 3-Scour Critical up to 7-Design Countermeasures Installed. We are requesting one proposal from Consultants for separate alternative analyses and plans, specifications, and estimate (PS&E) packages for each site with the intent to advertise each project separately. 2.2. Project Details Senn Road Bridge MP 0.87 Scour Repair The Senn Road MP 0.87 Bridge crossing Lucas Creek is a 60-ft long three-span concrete structure (built in 1966) supported by concrete piles. This structure will be the sole access for Senn Road residents after 2024 road reconstruction/bridge removal work at the south end of Senn Road. The Senn Road MP 0.87 (Lewis County Bridge No. 77) structure is classified as scour critical due to abutment/interior pier pile tip elevations within ten feet of the stream's thalweg. The Consultant shall perform a Scour Analysis that includes geomorphic, hydrologic, and hydraulic analyses to develop three (3) concept mitigation alternatives with probable cost estimates for County (and WSDOT Local Programs) evaluation. The Consultant will advance the County selected alternative to bid ready PS&E for construction. Wildwood Road Bridge MP 10.14 Scour Repair The Wildwood Road MP 10.14 Bridge crossing the So. Fork Chehalis River is a 124-ft long three-span concrete structure (built in 1955) supported by concrete piles. Wildwood Road is a through route and this structure can be closed during construction if necessary. The Wildwood Road MP 10.14 (Lewis County Bridge No. 03) structure is classified as scour critical due to abutment/interior pier pile tip elevations within ten feet of the river's thalweg. The Consultant shall perform a Scour Analysis that includes geomorphic, hydrologic, and hydraulic analyses to develop three (3) concept mitigation alternatives with probable cost estimates for County (and WSDOT Local Programs) evaluation. The Consultant will advance the County selected alternative to bid ready PS&E for construction. The anticipated schedule for these projects include final PS&E within 15-months of contract execution (utilizing WSDOT's Standard Consultant Agreement with applicable attachments and the Consultant's verified Overhead Audit costs). Consultant invoice charges shall be tracked separately for each bridge site. Project construction is anticipated to be completed in 2025. Although there are no DBE goals required, Consultants are encouraged to participate in a voluntary 10% SBE goal for completion of this project. 2.3. Eligibility Criteria Hydrologic, Hydraulic and Geomorphic Analysis, PS&E, and Design Support Scour Mitigation (Senn Rd MP 0.87 and Wildwood Rd MP 10.14) Scope of Services to be provided: Site Evaluation: Perform an in-depth site assessment to determine stream reach characteristics, channel composition, vegetation, bridge alignment, etc. for both projects. County will provide survey control data (horizontal/vertical datum) and existing right of way information. The Consultant shall provide all provide topographical survey required for both projects. Concept Options: Consultant will conduct a hydrologic and geomorphic analysis using available LiDAR, topographic survey data, SSURGO soils mapping, as-built drawings, previous upstream bank protection engineering reports (Senn Rd.), aerial photos, and findings from the field reconnaissance to identify processes contributing to existing scour conditions and estimating likelihood of future channel adjustments (i.e., long-term degradation and lateral migration). Consultant will develop three scour mitigation countermeasure design alternatives (using methods from FHWA HEC 18/23, WDFW, and/or WSDOT) and provide probable costs estimates for construction at both project sites. 100% PS&E: After preliminary plan options are reviewed by Lewis County (and WSDOT Local Programs), the Consultant shall advance the selected repair plans to 90% PS&E. -- to apply for all required environmental permits and identify construction easement areas/staging (right of way acquisition by Lewis County). Following Lewis County's review/approval of 90% PS&E, provide 100% PS&E to advertise for contractor construction. Note, due to outside funding authorization there may be a significant time lag from 90% plan submittal by the Consultant until 100% PS&E is requested. Environmental: The Consultant shall be Lewis County's authorized agent to apply for and obtain all required environmental permits, reviews, and documents necessary for this project. Anticipated documents/permits include: Archeological review for the project impacts and staging areas. All NEPA documentation for this FHWA funded project including farmland/forestry conversion. Ordinary high water and wetland delineation. Environmental Permits for in-water/near water work (Washington State Department of Wildlife's Hydraulic Permit Approval, USACE Nationwide Permit, Lewis County Fill & Grade, SEPA, etc.). Construction: During construction, the Consultant may be utilized as Lewis County's inspector during critical phases of the project and/or to answer contractor "request for information" emails. Post Construction Scour Evaluation: Following the completion of construction, the Consultant shall review as-built plans and provide a new Bridge Scour Evaluation (WSDOT Form 140-091) stamped by a Washington State Professional Engineer indicating the completed project satisfies WSBIS Code (NBI Code 113) to be rated 7--Design Countermeasures Installed. Question Submission Deadline:September 29, 2023, 4:00pm