Site work for a military facility in Walla Walla, Washington. Conceptual plans call for site work for a military facility.

Replacement of the existing two-leaf arch rib miter gate, including associated mechanical equipment and embedded components, at the McNary downstream navigation facility. The work includes removal and replacement of the embedded pintle ball and sill beam, demolition of existing wall quoins, sill beam, and pintle bases, and construction of new concrete foundations and embedded items. Each miter gate leaf weighs approximately 425 tons and measures approximately 53.5 feet wide by 106 feet tall. Each gate leaf shall be fabricated as a single piece in a certified fabrication shop using ASTM A709 Grade 50 steel in accordance with AWS D1.5 Bridge Welding Code, including requirements for fracture critical members. Fabrication facilities must hold the required AISC or hydraulic fabricator certifications with fracture control endorsement. Following fabrication, each gate leaf shall be shop coated using USACE System 5-E-Z impacted immersion vinyl coating by a certified coating contractor and delivered to the site by barge without segmentation. On-site construction activities include removal of the existing gate leaves using a heavy-lift crane, loading of removed gates onto barges, demolition of embedded concrete elements, installation of new sill beam and pintle bases, forming, placing, curing concrete, installation of new wall quoins with epoxy backing, and removal and installation of gate machinery. New gate leaves will be lifted directly from barges and set in place using a heavy-lift crane, followed by alignment of the gate leaves, installation and locking of quoin and miter seal blocks with epoxy backing, and final mechanical and functional adjustments. All site installation work is planned to occur within a 16-week navigation outage window, requiring coordination of heavy crane operations, barge deliveries, concrete placement and curing, mechanical installation, and final alignment and commissioning of the new miter gates. The magnitude of construction is estimated to be between $25,000,000 and $100,000,000. The Method of Contractor Selection has not been determined at this Time. *The value for this project is based on a financial range. The value is listed as the highest possible cost from the range provided by a stakeholder or official project document.