The following food safety guidelines were written for farms experiencing flooding and other severe weather. Guidelines in italics are specific to farms with GAP certification.

Direct Technical Assistance:

Documentation is essential to ensuring a farm’s food safety after a flood. If they have one, farmers should follow their food safety plans, designed to guide them through incidents such as floods or power outages. The Notice of Unusual Occurrence and Corrective Actions Form is a good starting point for documenting the incident and the damage. This form also has space for outlining corrective actions as they are implemented. Photos, receipts, and other documentation should accompany the form. GAP farmers will also need to conduct risk assessments, update testing and cleaning records, and re-train employees if conditions or practices have changed in light of the incident.

Crops In the Field and Land Use: If one of your growing areas has been affected by flood water, the crops in that field are not safe for human or animal consumption. Best practices include:

  • Exclude any rows or beds touched by flood water from harvesting. 
  • Exclude crops within 30 ft of the high water mark because pathogens can migrate through wet soil. 
  • Use flags to mark off areas affected by flood water.
  • Dispose of crops in a way that does not introduce contamination to “clean” crops.

Replanting after a flood requires farmers to consider the risks and allow enough time for soils to dry and microbes to die. Extreme soil sediment and erosion issues may require guidance from your local extension agent.

  • Conduct a thorough land-use risk assessment including adjacent land use.
  • Remove debris and when the soil is dry enough begin prepping your soil.
  • Wait at least 60 days after the flooding event before re-planting food crops.
  • Before planting, consider testing soil for human pathogens. (Wait at least 20 days after the flood water has receded before testing soil for human pathogens.)
  • If tests are positive for E. coli or other pathogens, consider re-working the soil to encourage microbial die-off and drying.
  • Before planting, consider testing soil for hazardous chemicals and heavy metals.
  • Additional clean-up efforts may be needed, including cover crops for phytoremediation and rejuvenation of soil life.

Water Quality: All water sources are vulnerable to contamination when flooding, landslides, and severe weather affect our farms. Surface water must be considered contaminated when it is part of a flooding event – both human pathogens and chemical contaminants are likely present at unsafe levels.  

Wells and municipal waters are also at risk. If boiling recommendations or use restrictions are in place for municipal water, it is unsafe to use that water.  Human pathogens and/or chemical contaminants are present in unsafe amounts. 

Any well that has been flooded or is within 30’ of the high water mark is also at risk for contamination. Topographical shifts, fallen trees, and other physical debris may also damage well casings or other water system infrastructure, introducing contamination through the cracks. 

If your water source was affected by severe weather, wait to use the water until acceptable water test results are obtained. Mitigation measures should be taken, or an alternative water source should be used.  A Water System Risk Assessment should be conducted before using the water source.

For well water:

  • Conduct a water system risk assessment.
  • Inspect your well for damage to the casing and for signs of a contamination source. 
  • Retest well water prior to using the water for crop production and other activities for generic E. coli. 
  • If tests come back indicating contamination, take the steps for shocking the well. Shock the well using chlorine bleach: Shocking a Well Video
  • If the well water is within acceptable limits, continue using well water as usual. 
  • If the well water falls outside acceptable limits, stop using the water, re-treat and retest until acceptable limits are achieved. 
  • Document any actions you take along with new water test results.