Study helps municipalities take a proactive approach to improving drinking water
If a community wants to improve its drinking water, one option is to spend money on upgrading equipment. But another option is to focus on how land upstream is managed, improving the water running off it and into connecting streams and rivers.
Depending on the location, improvements in upstream land management can be a proactive way for municipalities to improve water quality. This is why a team of researchers at the University of Georgia are working with several South Georgia municipalities, Georgia Power Co. and the Georgia Forestry Commission to determine the potential for this plan of action.
Faculty members Duncan Elkins and Susan Wilde and master’s student Wesley Gerrin at the UGA Warnell School of Forestry and Natural Resources have been analyzing land in the Middle Chattahoochee River Basin to identify parcels that, if conserved or restored, can have the largest impact on water quality in that area of the river.
“Our maps show areas of high priority that could have problems but can be fixed through management practices,” says Gerrin, who assisted in compiling color-coded maps representing areas of priority for conservation. Population density, size and proximity to waterways feeding into the Chattahoochee are all weighed to determine a property’s significance.
While a municipality may consider purchasing land, Gerrin and Elkins note that the project aims to determine a variety of factors—such as property cost, topography and the amount of land in the area that’s already conserved. The end product is a road map of sorts that municipalities can use as they plan the future of their water supply.
“This is a coarse model applied over a large area and any predictions would have to be validated by a site visit,” says Elkins. “But, it gives us a great idea for where to start looking for solutions if the reservoir monitoring starts to show excess nutrients are coming from a particular part of the watershed.”
On the map generated by Gerrin, parcels pop out as red, orange or green, signifying the highest—or lowest—of priority. Around Columbus, for example, many parcels are coded green, meaning the amount of cost and land management is not conducive to better management practices. Most heavily populated properties fall into this category, where buildings and roads make it difficult to get quality water runoff.
But there are also pops of red and orange on the maps, signifying key parcels that, if managed to encourage forest growth, can truly improve the water downstream. The approach follows studies that show water quality in forested areas is significantly improved compared with unmanaged or agricultural land.
As a result, the potential for watershed improvements over the long term is huge. It’s a model that has already proven itself in New York City, where the water utility purchased land upstream decades ago. Today, the city’s water quality is among the best in the country.
The study area touched on four Georgia counties that contribute to the supply of Columbus, Georgia: Harris, Meriwether, Muscogee and Troup. These counties are projected to increase in population by 23% over the next 30 years, according to state estimates, which puts additional pressure on acquiring land connected to the watershed.
The team is now assessing water quality downstream, in reservoirs near Columbus, for a larger assessment and a more detailed look at the smaller watersheds feeding into the Chattahoochee River. The result will be an even more detailed look at the watershed and ways to improve it over the long term.
“That’s where we hope to go in the future with this—to take this massive restoration priority map in our report and drill down to some specific areas that are contributing to poor water quality,” says Gerrin. “We can advise stakeholders that if they take some management action on this land, then they might have some effect.”