Crews unearth zoo history during 'Forest Hall' excavation

April 4, 2014 - 3:36pm

Work begins on state-of-the-art indoor portion of expansive new Elephant Lands

Construction workers at the Oregon Zoo unearthed an enormous chunk of history last week, excavating and removing the Eisenhower-era concrete moat that had encircled the zoo's elephant habitat from its 1959 opening until just around 20 years ago.

The 8-foot-deep moat, which hadn't been seen since an early-'90s remodel at the zoo, remained intact beneath many tons of earth in what was formerly the elephants' east sand yard. Concrete will be salvaged for re-use as structural fill — a reminder of both how far the zoo has come in the past 55 years and how far it plans to go, as progress continues on the $57 million Elephant Lands project.

Work on Elephant Lands entered a new phase March 24 when crews began laying groundwork for what will soon be known as Forest Hall — the spacious, state-of-the-art indoor portion of the habitat.

And while the site isn't much to look at now, artist's renderings and interviews with zoo staff provide a stunning preview of what the building will look like once complete: a vast, sunlit arena housing one of the largest, most innovative indoor elephant spaces in the country.

With natural light streaming in through large overhead skylights, the zoo's elephant family will move across a lush, forested backdrop seen through a 1,820-square-foot glass curtain wall.

"It will be like daylight indoors," zoo construction manager Jim Mitchell said.

Elephants won't be the only species benefitting from the design: The large windows of Forest Hall will be fashioned from avian-friendly Ornilux glass, transparent to the human eye but easily perceptible to birds. Wildlife biologists estimate hundreds of millions of birds die each year in North America by colliding with windowpanes they are unable to see.

An elephant-sized "air curtain" separating Forest Hall from the outdoor areas will maintain a constant, comfortable indoor temperature for pachyderms and visitors while providing the herd around-the-clock access to the rest of Elephant Lands' 6.25-acre spread.

"The great thing about this feature is that the elephants get to choose whether to be indoors or out," said Bob Lee, the zoo's elephant curator. "It won't be us making decisions for them."

Adjacent to Forest Hall, a spacious new indoor holding area — with three 1,600-square-foot stalls for elephant care — will replace the zoo's current holding area, which, like the long-buried moat, dates to 1959. Together, the two facilities will sit on 32,000 square feet, with a roof reaching up to 36 feet at its highest point. Both indoor spaces will be filled at least four feet deep with sand to cushion and protect the elephants' feet.

You can make a difference

Help make Elephant Lands even better. Join the Campaign for Elephants.

While it won't be readily apparent to visitors, the structure's rooftop will feature a huge array of solar panels as well as an 8,600-square-foot green-roof system designed to save energy, decrease stormwater runoff and absorb carbon dioxide.

Materials from the zoo's Lilah Callen Holden Elephant Museum, which closed last year, will be incorporated into visitor areas within Forest Hall, showing how Asian elephants have interacted with and inspired humans for thousands of years — and illustrating the strong bond between the Portland community and the Oregon Zoo's elephant family.

And visitors can enjoy education and conservation activities, made possible through the Oregon Zoo Foundation's $3 million Campaign for Elephants. The foundation has already raised more than $2.3 million toward its goal. To learn more or to make a gift, call 503-220-5707 or visit

Elephant Lands — which will be four times larger than the zoo's current elephant habitat — will extend around most of the zoo's eastern end, from south of the concert lawn north into the area that formerly housed Elk Meadow. The entire habitat will be completed in fall of 2015.