Agricultural water versus indirect water
The Food Safety Modernization Act (FSMA) regulates irrigation water testing in growing fresh produce and what water needs to be tested. Recent changes have been made that can make a difference in the amount of testing required of growers.
March 29, 2016 - Author: Phil Tocco, Michigan State University Extension
The U.S. Food and Drug Administration’s (FDA) Food Safety Modernization Act (FSMA) is the most sweeping legislation regarding raw agricultural products since 1938. Recently, the FDA published the final FSMA Rule and it is extremely complex. One area of particular complexity is the issue of irrigation water testing and what water needs to be tested. Some very important points were clarified that slightly alter who might need to sample irrigation water.
The act classifies two types of water used in the field: agricultural water and indirect water. If water comes into direct contact with the harvestable portion of a plant, it is considered agricultural water. If a grower uses overhead sprinklers to irrigate a lettuce field, it would be considered agricultural water. The second type of water is called indirect water. In this case, the water would not come into direct contact with the harvestable portion of the plant. If drip tape under plastic is used to maintain tomato plants, this would be considered indirect water. The single biggest change in this definition is the use of the word “harvestable” instead of the word “edible.”
In some cases, no matter how a grower wishes to water a particular crop, it will always come into contact with the harvestable portion of the plant. Carrots are a case like this. Even using drip tape, the harvestable portion of the crop will come into direct contact with the water. That change in wording helps drive this change in implementation.
Sometimes the plant stage dictates whether a particular type of water is either agricultural or indirect. Sprinkler irrigation of blueberries from bloom through harvest would be considered agricultural water. The same source of water delivered in the same way would be indirect water when used after completion of harvest. Likewise, frost protection sprays that are simply protecting tender buds would be indirect water, so would water applied at planting for vegetable transplants.
These differences seem like small points, but they can have a big impact in the cost of sampling under FSMA. FSMA requires that surface water used for agricultural water be tested five times a year before harvest for generic E. coli. There is no testing frequency proposed for indirect water.