Colorado officials are working with farmers to address potential crop and soil contamination after severe flooding hit Northeastern Colorado last month. Their biggest challenge will likely be assessing flood-affected fields before replanting and analyzing affected water before fall irrigation. So far, state officials and others are confident that only safe products from the state will reach the market.
“Flooding events can present a potentially hazardous public health risk,” states the industry guidance document created by the U.S. Food and Drug Administration (FDA) in 2011 after Hurricane Irene caused severe flooding on farmland in Vermont, New York, and New Jersey.
The FDA guidance states that floodwaters may be exposed to sewage, chemicals, heavy metals, pathogenic microorganisms or other contaminants. Even if floodwaters do not come into contact with a crop, they can still cause microbial contamination, and plants may take up chemical contaminants from the soil. Additionally, the soil and plant life could develop mold and toxins from standing water.
So far, the floods have caused more than 37,000 gallons of oil to spill into or nearby rivers and also dislodged wastewater storage tanks used for hydraulic fracturing (“fracking”). Other dangers in the floodwaters include fertilizers, pesticides, animal manure, human sewage and animal carcasses.
The FDA guidance instructs producers to properly dispose of any crops that have come into direct contact with floodwaters. Other crops must be evaluated on a case-by-case basis.
The Colorado Department of Agriculture (CDA) does not have an estimate for the amount of crops impacted by the floods because the fields are under too much standing water to evaluate the damages. CDA did confirm that corn was the only animal feed left in the fields. If the corn is harvested, then CDA can test for contamination under its usual testing program.
Because most sources report that the floodwaters mostly impacted fields without crops, the more important evaluation will likely be an assessment of flood-affected fields before replanting.
Evaluating whether farmland is contaminated largely depends on whether the farm was flooded by excess precipitation or rising bodies of water, according to Elizabeth A. Bihn, Ph.D., director of the Produce Safety Alliance. A field is more likely to be contaminated if it was flooded by a nearby water source, she said.
“The biological and chemical risks from an overflowing river are much different than soil runoff from your own field. When a river overflows, who knows what is in the water? It could be anything in the vicinity of the river, including oil, gas, and even animals,” Bihn said.
According to the Colorado Department of Health and Environment (CDPHE), rising rivers likely caused the majority of flooding in Colorado. While precipitation amounts were unusual for the state, rain alone would not have caused such a high volume of standing water.
In addition to evaluating flood-affected fields, producers will have to evaluate the safety of irrigation water. The Colorado State University (CSU) Extension Service says that it is working with CDPHE and FDA on guidance to determine whether potentially contaminated pond water can be used for irrigation this fall.
Overall, the CSU Extension Service has been the key resource for flood-impacted farmers. It has focused efforts so far on disseminating information, but its representatives have indicated that the next phase will likely involve soil and water testing as well as individual farm evaluations.
The CSU Extension Service does not yet have details on water and soil testing or on how land will be evaluated. Marisa Bunning, Ph.D., a food-safety professor at CSU and an Extension Specialist, said that they are learning as much as they can from flood events that have occurred in other states, but that every flood is different. And, according to Adrian Card, a Boulder County Agriculture and Natural Resources Extension Agent, evaluating contamination issues will vary depending on the location and specifics of the land.
CDPHE does not yet have plans for testing or field evaluations and is directing farmers to work with the CSU Extension Service and consult the FDA guidance document.
Farmers and producers have the ultimate responsibility for ensuring the safety of their crops and fields. The FDA guidance, which is a non-binding set of recommendations, states, “Assuring the safety of flood-affected food crops for human consumption is the responsibility of the growers that produce and market these crops.”
Although not formally documented, Bihn said that most farmers she talked to after the Irene floods followed the FDA guidance document. She is confident that Colorado farmers will also follow it to address food-safety issues.
“Farmers are a very dynamic group of people. They are problem-solvers,” Bihn said. “Dealing with unexpected weather patterns is what they do.”
Similarly, Card noted, “Colorado producers have a strong history of superior crop quality. Since our recent food-safety issue with cantaloupe, growers are acutely aware of the need to ensure safe, nutritious and flavorful produce.”
Farm-related organizations in Colorado such as the Rocky Mountain Farmers Union, the Colorado Cattlemen’s Association, and the Colorado Farm Bureau (CFB) have reached out to impacted farmers. CFB, for example, has set up a disaster fund to aid impacted farmers and ranchers.
Also, farmers in the region are focused on assuring the quality and safety of their fields and products.
“The first priority was about saving lives and finding out where people were. The second priority has been an assessment of the physical damage of the property,” said Kent Peppler, a Mead-area farmer and president of the Rocky Mountain Farmers Union. “The third priority will be environmental impact and certainly public health.”