8 No. 5
Just Add Water
An interdisciplinary experiment
Reading and Resources
"Why do Atlantans not know that there are massive river
systems throughout the state, that a major river runs through the city, that the city dumps all these effluents into it?"
"When the impervious [surface] area rises to 30 percent,
the stream habitat becomes completely degraded. On campus,
we have greater than 50 percent impervious area."
A social watershed
Water as Sacred
Jewish and Christian traditions
The Rarest Element
Despite centuries of research, mysteries of water remain
Anne Hall: How is Emory unique in the way that we now address sustainability and water-related issues?
John Wegner: Emory is special in that we adopted the U.S. Green Building Council’s LEED (Leadership in Energy and Environmental Design) Program early in 2000. The goal of the leed program is to reduce the ecological footprint and overall environmental impact of new building—from the construction phase to the operation of the building over time. leed-certified buildings, such as the new Math and Science Center, use rainwater for landscape irrigation and low-flow plumbing fixtures to conserve water. A water quality device removes 40 percent of the phosphate and 80 percent of the particulate matter that contaminates storm water runoff from the roof, sidewalks, and streets adjacent to the building. The Whitehead Biomedical Research Building was designed with the ability to recover condensate from the indoor air circulating in the building and harvest that water for use in the cooling towers that supply chilled water for the Emory campus. Last year the total amount of water saved by condensate recovery was over 4.5 million gallons, double our initial estimates. Emory now has four leed-certified buildings, more than any other American university, and all of the new construction on campus will continue to be LEED-certified. In addition, the new campus master plan has set aside 55 percent of the Emory campus for green space, protected from new development. Maintaining a larger forested area on campus will decrease the amount of storm water runoff into streams and help improve stream habitat and water quality.
AH: How is water management addressed in the “Sustainability Vision for Emory,” a principle guiding the strategic plan for the university?
JW: Part of that vision involves stream bank restoration, a storm water management plan, a green building program that would evaluate water use, and restoration of forests on campus. One stream bank restoration project involves Antoinette Candler Creek, a small stream that runs through Baker Woodlands, then under Dowman Drive and Oxford Road to join Peavine Creek. Peavine Creek eventually joins tributaries to the Chattahoochee River—the source of Atlanta’s drinking water. When the proposed roundabout is constructed as part of the Emory Village revitalization program, the stream banks of Antoinette Candler Creek will be restored. Severe erosion is evident in the exposed tree roots and undercut banks of this creek. The banks will be sculpted back into more natural contours, and native plant species will be planted to help stabilize the soil and prevent further stream bank erosion. The goal for storm water management is to restore the natural hydrologic cycle on campus to what it was originally, when the entire campus area was forested. In watersheds, where impervious surfaces such as sidewalks, rooftops, and streets make up more than 10 percent of the land area, changes are evident in the stream channels and water quality. Impervious cover generates over ten times more storm water runoff than forested areas. Increased storm water runoff can wash pollutants into streams, increase flooding, erode stream banks, increase the sediment load of the stream and increase sensitive habitat loss. When the impervious area rises to 30 percent, the stream habitat becomes completely degraded. On campus, we have greater than 50 percent impervious area, so our goal in the storm water management plan is to restore the streams back to their original forested condition. We can accomplish this by installing vegetated green roofs that allow absorption of rainfall, by constructing retention tanks or ponds to hold storm water runoff, and by laying down infiltration beds to allow heavy rainfall to naturally infiltrate into the soil.
AH: How are students in your courses involved with watershed management projects?
JW: This semester in my course on The Ecology of Emory, the students are going to work on a management plan for Wesley Woods. Since the South Fork of Peachtree Creek runs along the edge of the forest there, one of the components of the management plan will be to evaluate the health of the stream and the condition of the stream banks. Another task students will be involved in is helping to evaluate storm water management plans that are being presented to the university this semester. The students will read the request for qualifications documents that are submitted and also will attend the presentations by the companies that we are interviewing. Water management will also be a central issue when we review the leed standards for the Math and Science Center and determine the ecological footprint of the building.