Water Quality Index for Agricultural Runoff, Streamlined and Accessible
By Spencer Miller
Scientists at the USDA’s Natural Resources Conservation Service recently developed a simple, web-based tool that helps producers easily understand the quality of water flowing off their fields – the Water Quality Index for Agricultural Runoff (WQIag).
“Water quality is complex,” said NRCS National Water Quality and Quantity team leader Shaun McKinney. “Experts usually focus on one aspect of water quality – such as temperature, nutrients or pesticide content – instead of thinking about a more complete picture.”
Conversations about water quality quickly become technical and scientific, often leaving most non-scientists behind.
“This is a problem. How can we talk to producers about improving water quality when we can’t explain it in a clear way?” said McKinney.
So the NRCS scientists worked on developing the best tool that could clearly communicate to the farmers and ranchers.
“Our solution was inspired by the Dow Jones Index. We wanted to represent something very complex with a single, easy-to-understand number,” said team member and environmental engineer Harbans Lal. “The challenge was understanding the science well enough to translate it into something accurate, yet accessible.”
On the WQIag website, producers input information about their field, such as slope, soil characteristics, nutrient and pest management, tillage practices, and finally, conservation practices. The WQIag calculates these variables into a single rating on a 10-point scale: 0 being very poor; 10 being excellent.
Though some variables – such as slope and soil type – won’t change, producers can adjust other factors for a quick estimate of how conservation impacts water quality. A few clicks calculate the value of less tillage, less fertilizer and other conservation practices, which makes it versatile to use.
“This tool is equally useful for corn farmers in Ohio and coffee growers in Hawaii. The WQIag is going to help us all get on the same page,” said McKinney. “It gives us the vocabulary for a conversation about water quality.”
That conversation has already started, based on early feedback. NRCS partner Field-to-Market has adapted the WQIag for their use, offering it as part of their fieldprint calculator. McKinney and his team said feedback from NRCS field technicians has been positive.
“The WQIag is still in the pilot phase, but we’re getting a lot of useful feedback. We’re using that feedback to fine tune the software and make it even better,” said Lal. “We hope to eventually offer the WQI as a free smartphone app.”
NRCS encourages producers to visit their local field office and discuss WQIag results and water quality improvement strategies with technical experts.