Wenqing Xu, Fontenot, Kathryn
Floodwaters commonly contain microbial contaminants and can directly affect public health. Microbial contaminants may include bacteria, viruses and parasites. Common foodborne pathogens reported in floodwater include norovirus, Salmonella, Escherichia coli, Cryptosporidium and Giardia. Following Hurricane Katrina, fecal coliform concentrations increased in floodwater at all locations tested in New Orleans.
Floodwater exposed to raw sewage, farm animals (such as chickens or goats), river or pond water and agricultural runoff is likely to carry harmful pathogens and parasites and thus spread health risks to fresh produce in your home garden.
Gardeners and other people who handle and/or consume fresh produce exposed to floodwater are at risk of gastrointestinal ailments (vomiting, stomach cramps and diarrhea) or other severe illnesses. In addition, infants and young children, elderly, pregnant women or people with compromised immune systems are at higher risk of becoming ill from handling or consuming contaminated fresh produce.
It is best to wait until the soil has fully drained and the top 2-3 inches of the soil has completely dried out before replanting.
Centers for Disease Control and Prevention. 2012. Guidance on Microbial Contamination in Previously Flooded Outdoor Areas. Available from: http://www.cdc.gov/nceh/ehs/publications/guidance_flooding.htm#1
Pardue, J., Moe, W., McInnis, D., Thibodeaux, L., Valsaraj, K., Maciasz, E., van Heerden, I., Korevec, N., and Yuan, Q. Z. 2005. Chemical and microbiological parameters in New Orleans floodwater following Hurricane Katrina. Environmental Science & Technology. 39(22):8591-8599.
Donovan, E., Unice, K., Roberts, J.D., Harris, M., and Finley, B. 2008. Risk of gastrointestinal disease associated within exposure to pathogens in the water of the lower passaic river. Applied and Environmental Microbiology. 74 (4): 994-1003.
Schmid, D., Lederer, I., Much, P., Pichler A. M., and Allerberger, F. 2005. Outbreak of norovirus infection associated with contaminated floodwater, Salzburg, 2005. Eurosurveillance, 10 (24). Available from: http://www.eurosurveillance.org/ViewArticle.aspx?A...
Schets, F.M., Wijnen van J.H., Schijven, J.F., Schoon, H., Roda Husman de, A. M. 2008. Monitoring of waterborne pathogens in surface waters in Amsterdam, the Netherlands, and the potential health risk associated with exposure to Cryptosporidium and Giardia in these waters. Applied and Environmental Microbiology. 74 (7): 2069-2078.