Phipps Center for Sustainable Landscapes

“When we think about the type of world we would want our children and grandchildren to inherit, it is easy to see why the Living Building Challenge is so important. And when we look at how a dedicated team of professionals came together to create the CSL, we know that we have the technology and capacity to create that future now.”

– Richard V. Piacentini, Executive Director
Phipps Conservatory and Botanical Gardens

The new Center for Sustainable Landscapes at Phipps Conservatory and Botanical Gardens in Pittsburgh, Pennsylvania, opened in January 2013, more than six years after conceptual discussions began. For a historic non-profit institution and cultural gem like Phipps, whose primary inhabitants are some of nature’s fi nest botanical specimens, waiting for things to grow and bloom is not unusual. This project, however, will soon set a precedent in high-performance design both locally and internationally, and everyone, it seems, is eager to see the fruits come to bear.

In 1999, the groundwork was laid for a three-phased master plan for renovation and expansion at Phipps. Phase I, the new Welcome Center, was the first LEED®- certified visitor center in a public garden. Phase II’s Tropical Forest Conservatory is now known as “the most energy-efficient conservatory in the world,” and the production greenhouses were recently certified Platinum under the LEED EBOM program. Phase III was slated to be a new center for education, research and administrative operations.

And so began the life of the Center for Sustainable Landscapes (CSL). In late 2006, Phipps’ Executive Director Richard V. Piacentini championed a sustainable design for Phase III that aligned with the International Living Future Institute’s groundbreaking green building process, the Living Building Challenge.

The Challenge states: “Imagine a building designed and constructed to function as elegantly and efficiently as a flower.” Version 1.3 of the Challenge (which is updated periodically) included sixteen imperatives that a project must fulfill. These imperatives are distributed among six performance areas, also known as Petals: Site, Energy, Materials, Water, Indoor Quality, and Beauty & Inspiration.

CEC led final development of the strategy that addressed the Water Petal and its two imperatives: net-zero water and sustainable water discharge. The strategy included on-site sanitary treatment, stormwater management, and water reuse systems. A closed-loop system for the biological treatment and filtration of sanitary water includes two constructed wetland cells, two sand filtration beds and an ultraviolet filter to disinfect water for reuse as greywater (or flush water) within the CSL. This system significantly reduces the CSL’s need to draw potable water from the city’s system, in addition to minimizing the impact on municipal sewage treatment.

The design also involved harvesting the Pittsburgh region’s abundant rainwater. A 1,700-gallon underground cistern stores rainwater for irrigation at the CSL, as well as backup water for the sanitary reuse system. An 80,000-gallon underground modular rainwater harvesting tank captures additional site stormwater runoff. Harvesting some of the estimated 2.7 million gallons of rainwater that will fall on the CSL site annually will significantly reduce the burden on the city’s stormwater management system and the entire Phipps campus’s need to pull potable water.

A lagoon system manages runoff and serves as a biological stormwater treatment system, similar to the natural treatment that occurs in wetlands and marshes. With its reflecting pool-like quality, trickling water sounds, elegant landscaping and inviting boardwalk, the lagoon is one of several connected landscape communities that continue the main conservatory experience throughout the CSL site.

“High-performing buildings don’t just get switched on,” said Michael Takacs, CEC Principal and head of the Landscape Architecture practice. “They require additional time to adjust and fi ne-tune their operational parameters. All of the circuitry and programming for these components are in place, but making them talk to one another the way they are intended must be adjusted manually over time.”

Phipps has been conducting performance monitoring of all the different spaces for treatment on site. “As a conservatory and botanical garden, it’s important to know exactly what is being put on the plants. A big part of what we’re doing now is periodic water quality testing to examine what is going in versus what is coming out,” said Jason Wirick, Phipps’ Director of Facilities and Sustainability Management.

“Our hope is to showcase the performance of more passive and sustainable site water systems,” Wirick said. “CEC cares about the project and about what we’re doing at Phipps.”

The CSL achieved LEED Platinum certification from the U.S. Green Building Council in September 2013, and received a Green Design Citation at the AIA Pittsburgh Design Awards in October 2013. Along with the Living Building Challenge, the CSL is currently pursuing the Sustainable Sites Initiative™ SITES™ certification for landscapes.