Oregon Zoo Elephant Habitat

CLIENT Oregon Zoo

Location Portland, OR

Oregon Zoo's beloved Asian elephants were promised a spectacular new home, expanding their habitat from 1.5 to 6.25 acres.

This project reinvented the elephant habitat and exhibit space and included a new LEED-Silver elephant building, a service road to relieve congestion in visitor areas, various retaining walls, a Zoo Train realignment, and the new Forest Hall large indoor habitat building with a raised visitor viewing area.

The project was in a geotechnically challenging environment that encompasses a massive active landslide hazard zone. Shannon & Wilson, who had been performing studies on the site since 1969, performed a complex geotechnical study and developed foundation reports for cost-effective foundations to support new buildings and facilities, reducing the risk of reactivating ancient slide masses during extensive earthwork. During construction, we provided geotechnical support, including construction observation and special inspection.

Working around a landslide in a highly built-up site demanded ingenuity. Because there was no cost-effective way to fix the landslide, design solutions had to accommodate some movement - in some areas, up to two inches. Elephant Lands would occupy 15% of the Zoo campus, and some identified expansion space, such as the North Habitat, was too steep and damp. In response, the team engineered the slope to support an expanse of soft sand substrate-essential for elephant foot health-with a layered drainage system to prevent the fill from sliding. The team also "created" land using retaining walls and careful, balanced hillside cuts, all while preserving significant trees. Elephant Lands borders on nearly all other campus exhibits, but the Zoo reported no dip in attendance or complaints during construction. In fact, the project itself became an "exhibit," with humorous interpretive signs identifying the "species" of heavy equipment.

property development Community Spaces
Laboratory Instrumentation Geotechnical Engineering Geologic Hazards Construction Management


ACEC Oregon Engineering Excellence Awards - Honor Award


Adrian Holmes

Aimee Holmes
Senior Engineer & Geologist

Alia Hubbard
Senior Environmental Scientist

Jerry Jacksha
Senior Associate

Elliott Mecham
Senior Associate

Cody Sorensen

James Walters

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