Brookhaven will try to improve the quality of its water and soil through a partnership with the University of Georgia.
The city approved a one-year, $150,000 agreement with the University of Georgia Warnell School of Forestry and Natural Resources on April 26, according to a press release. That agreement was for a study to evaluate how biochar might enhance the quality of surface water and soil.
Biochar is the residual material that’s left after burning organic materials like waste wood, according to Dr. Daniel Markewitz, professor of soil site productivity at the Warnell School.
“If you burn wood in a fireplace there is abundant oxygen, and the residue is ash or charcoal,” Markewitz said in an email. “To produce biochar, you need a fireplace (or kiln) that can control the oxygen input.”
According to the press release, a research team will collect and analyze baseline water quality data from Murphey Candler Lake as well as from stormwater runoff in the area. The team will then place biochar-filled bags at stormwater runoff discharge points to test biochar’s ability to remove nutrient-laden sediment from the water.
“Biochar’s best quality for water purification is its large surface area and thus an ability to adsorb nutrients from the water,” Markewitz said. Adsorption refers to the accumulation of molecules at the surface, which is different from the absorption of water into a sponge.
The team will then evaluate the potential for biochar soil to affect healthy growth of plants. Markewitz said the idea is to “close the cycle and put this wood waste back in the woods or the soil.”
“We will evaluate benefits to both grass and trees,” Markewitz said. “If trees are responsive, we will evaluate the benefits of using biochar in urban street trees (or tree vaults) at planting or as a top dressing.”
The research team will conduct water quality assessments and field trials in and around North Nancy Creek, Nancy Creek, and Murphey Candler Lake, according to the press release.
“This exercise is another aspect of the vision of Sustainable Brookhaven,” said Mayor John Ernst in the press release. “We want to see if we can take what was going to the landfill and repurpose it as great big water filters. Then the question becomes, can the used water filters then become a type of fertilizer?”
A spokesperson for the city said they do not know the specific date for when the bags will be installed, but it will be later this summer.
