Reduced Levels of Herbicide Atrazine Make Lake a Safe Source for Drinking Water
By April Smith
Texas Cooperative Extension (TCE) played a big role in helping reverse a serious pollution problem in Aquilla Lake in Hill County, according to Dr. Allan Jones, director of the Texas Water Resources Institute (TWRI) and close collaborator of TCE.
The Texas Commission on Environmental Quality (TCEQ) has confirmed, and extensive sampling now shows, that Aquilla Lake has been fully restored as a safe source for drinking water because of the combined efforts of local farmers and facilities, regional agencies and state government.
“The range of participation from the state level to the local level was crucial in reestablishing Aquilla Lake as a source of drinking water,” said TCEQ Chairman Kathleen Hartnett White. “The Lake is a protected and precious resource to the people of Hill County, and we will continue to work with local farmers to ensure it remains so.”
TCEQ listed the body of water as “impaired” after high levels of atrazine, an inexpensive, effective weed suppressant used on crops, were detected. Atrazine can wash off from recently treated fields during rain showers into ditches and streams that eventually carry the herbicide into the lake.
In response to the listing, a broad-based coalition with several agencies and organizations was initiated to lessen atrazine runoff. Active participants include the Texas Department of Agriculture, TCEQ, Texas State Soil and Water Conservation Board (TSSWCB), the Texas Watershed Protection Committee and TCE.
The coalition prepared a total maximum daily load (TMDL) analysis that identified the sources of atrazine pollution and developed a plan to reduce atrazine pollution. More than 600 potential contamination sources, such as fertilizer and pesticide fields, were identified in the Aquilla watershed.
The TMDL could have prohibited regional farmers from using this economical, popular herbicide on crops unless atrazine runoff could be controlled. Some estimates suggested farmers in the region could lose thousands of dollars if atrazine were restricted. In response to this, the coalition identified sources of cost-share funding, making it more economical for farmers to adopt best management practices (BMPs) to improve water quality.
At the same time, TCE teamed up with several soil and water conservation districts in the region to personally work with farmers to show them how atrazine was affecting the quality of the lake and to implement farming methods to reduce atrazine levels. Area farmers then took the initiative to re-examine their own growing practices. Since this coordinated effort began, almost 100 percent of area farmers have voluntarily adopted new practices that prevent or reduce atrazine runoff to area streams.
“Due to the level of cooperation, we were able to solve the atrazine problem in only a few years,” said Monty Dozier, Extension Specialist in the Department of Soil and Crop Sciences at Texas A&M University. “Everybody came together to create a plan and we worked with the farmers and other stakeholders to make it succeed.”
Since high atrazine levels were detected in 1997, the Aquilla Water Supply District, which treats lake water and delivers it to area residents, added additional treatment methods at the drinking water plant. The District has also carefully monitored treated water in the plant to assure they are delivering safe drinking water to the public.
Water samples collected from the lake from 2001 through 2003 indicate atrazine concentrations in the reservoir are down by 60 percent, bringing annual averages for atrazine well below the required safety level for treated drinking water.
“I’ve been working with water quality issues for more than 10 years, and I’ve never seen a project that’s been this successful,” said Kevin Wagner of the TSSWCB.
“This is an excellent example of governmental entities, involving regulatory, educational and financial assistance, working on a voluntary basis with landowners to achieve desired environmental goals,” said Jones of the TWRI.
