By Clint Thompson
Rains from storms and other tropical events help replenish the soil moisture. However, they also provide food safety concerns for fresh produce growers. Camila Rodrigues, assistant professor and Alabama Extension specialist in Horticulture at Auburn University, says the biggest concern is with runoff.
“What is around the field that could be carried around by runoff and also be contaminating everything around?” Rodrigues said. “A lot of small growers here in Alabama have livestock on their farm. Getting animals near the field with runoff is concerning. Also, some growers, they do keep composting around as well. Runoff can be a huge problem, especially if you’re keeping raw manure nearby.
“The water that is used to irrigate the crop, normally it’s down the hill and you have huge runoff coming into the water. When they use that water, that is a big issue.”
Runoff occurs when water drains from the surface of an area of land. It usually happens when there is a heavy rain event, like a thunderstorm or hurricane. If contaminated water touches an edible fruit, it creates a food safety risk.
Rainfall events were above average this summer in the southeast U.S., especially in Louisiana, Alabama, and Georgia, according to the National Center for Environmental Information. It becomes a challenge for crop management and also a food safety concern to fresh produce growers.
Excessive rainfall leads to runoff of soil and contaminants to lower areas of vegetable and small fruit fields. These are typically where irrigation water sources are located. In the most extreme cases, field flooding can compromise the entire crop. Here’s some info to help growers navigate flooding concerns: https://www.aces.edu/blog/topics/crop-production/food-safety-for-southern-u-s-food-crop-producers-after-flooding/.
Growers need to watch rainfall events closely and then follow with a microbial water testing to maintain safety levels used in the field.
“Water is the major contributor to fresh produce contamination in the field, so monitoring potential risks of contamination is important to avoid future foodborne outbreaks,” Rodrigues said.
Water testing should be done prior to the growing season and increased during rainy periods. Water samples should be collected from irrigation ponds or wells and sent to local labs for microbial water analysis. This includes total coliforms and generic E. coli testing. For further information related to agricultural water standards under the Produce Safety Rule and water testing, visit https://producesafetyalliance.cornell.edu/sites/producesafetyalliance.cornell.edu/files/shared/documents/Insights-to-get-you-organized.pdf.
Growers may contact their local Extension agents and Extension specialists in need of assistance on properly monitoring water quality and how to interpret testing results.
“Heavy rainfall is always a food safety concern. I think growers see the damage to their crops, but a lot of them don’t think about the food safety risk, especially when irrigating their crops with potentially contaminated water,” she added.