Turner hits milestone at $160M Seattle Aquarium expansion

The project team completed the concrete pour for the curved main tank at the facility's new Ocean Pavilion.

Turner Construction reached a milestone in November on the $160 million Ocean Pavilion expansion at the Seattle Aquarium by completing a more than 23-hour concrete pour on the facility's new main tank, according to an email update shared with Construction Dive.

The tank's structure includes a 2-foot-thick curved concrete wall and was built with 355 tons of rebar and 680 cubic yards of concrete, or four times the amount of rebar used on a typical core, according to Turner. The concrete form will essentially serve as the backdrop in the main tank, which visitors will view through acrylic windows fitted to the opposite side of structure.

Since the forms for the shell-like tank shape essentially had no straight edges, Turner and its project partners created 229 panels shaped by a CNC router and foam-glued to Peri Group backing that were then sprayed with truck bed liner material to create a uniform surface.

The project team leveraged Rhino and Grasshopper 3D software to create the double-curvature concrete geometry for the 362,000-gallon tank

Turner is targeting net-zero emissions and net-positive energy for the Pavilion, while analyzing embodied carbon in the new build. Turner Project Executive Stuart Kibbee said the firm has been meticulous in building material selection to make sure the products are free of toxins, while minimizing plastics, vinyl, biocides and so-called Red List materials.

The Ocean Pavilion will be home to 3,500 sustainably sourced animals, including apex predators such as sharks and rays, fish ranging from wrasses, grouper, trevally and butterflyfish and up to 30 species of corals, anemones, sea stars, giant clams and other marine life. The habitats will also feature mangrove trees — critical sources of shelter for young fish.

Looking ahead, Turner said that construction milestones that will be achieved by the end of December are completion of the shell, core and roof, main exhibit form, habitat structures and installation of habitat acrylic windows and animal life support systems.

Construction on the Pavilion, designed by LMN Architects, has been underway since 2020. The new facility is expected to open in summer of 2024.