Phoenix Convention Center, Phoenix
Green wall size: 1,400 square feet
Award recipient: Ten Eyck Landscape Architects (design landscape architect) Project Team
Architect: Populous
Client representative: Phoenix Office of Arts and Culture
Initial design for condensate treatment: Wass Gerke & Associates
Landscape architect of record: A. Dye Design
Landscape contractor: AAA Landscape
Mechanical engineer: Syska Hennessy Group
Structural engineer: Magnusson Klemencic Associates

In a quest to make the desert city of Phoenix more comfortable, sustainable, and more in harmony with its natural environment, the leaders of this project created a habitat garden that thrives on its urban structure. The living wall was inspired by the sheltered canyon habitats of the Sonoran Desert and the settlement of Hohokam Indians that lived on the site. As an adaption to limited water resources, it was proposed that condensate from the building’s air conditioning system be used to support the garden. 

At its peak flow, the building generates over 800 gallons of condensate water per day from 15 of its air handling units. Typically this water would be directed into the sanitary sewer system. Now, however, it is collected, stored, and used for irrigating the garden. Condensate is harvested and stored in two collection tanks. One of the tanks is located on the second floor of the Phoenix Convention Center, where a window to building condensate collection point is a visual display to the condensate collection point before its entry into the habitat garden.

The harvested condensate is UV-treated for purification, then pumped outside. In celebration of water’s movement, the purified condensate descends through three stainless steel discs, trickling down an Arizona rain chain before its journey through a steel angle channel to the living wall. 

The overstructure living wall is constructed of steel columns, wire mesh, light weight soil, filter fabric, volanic rock, and is planted with a native seed mix and seedlings such as Octopus Agave, Yucca, Chuparosa, and Brittlebush. All water runoff from the wall is diverted via runnels to an adjacent sunken water harvesting garden. The gardens and architecture do more than just exist together; they each make it possible for the other to thrive. The building supplies the desert gardens with condensate water and the landscape provides comfortable outdoor gathering spaces. 

Steven W. Peck is the founder and president of Green Roofs for Healthy Cities, the non-profit industry association with a mission to develop the green roof and wall industry across North America. For more information visit greenroofs.org. Readers are invited to join GRFHC at CitiesAlive to meet the award winners and learn more about these outstanding green roof and wall projects: citiesalive.org.

More information on the 2011 Winners