Irrigation
Farmers in some regions depend entirely on rainfall to provide water for growing crops, while in arid regions, artificial irrigation is the norm. While it’s true that water from rainfall may not be perfectly pure, artificial irrigation provides far more opportunities for contamination.
Irrigation water can come from virtually anywhere, but farmers should generally use the highest possible quality water to minimize problems with cross-contamination. To achieve this, it’s critical that farmers protect their agricultural water sources. This means frequent testing of well water, ensuring that source aquifers are overdrawn, preventing outside water from seeping or flowing into storage basins, etc. Hazardous substances such as pesticides, herbicides, excess nutrients, and fecal contaminants from animal or human sources can be hard to remove, so water with these contaminants requires careful treatment before it’s safe to be reapplied to crops or released into the environment. Use of contaminated irrigation water can injure crops, poison the soil, and even harm local ecosystems and waterways if runoff is allowed to escape into the environment.
Post-Harvest Water
Using carefully sourced water is critical in fresh fruit and vegetable production. The use of unsafe water can move harmful microorganisms such as norovirus and listeria across large areas or large volumes of product. The water source itself and how and when the water is applied greatly influence the level of risk for crop contamination.
Crops that are intended wholly for processing, such as wheat and barley, or those destined for canning and other prepared foods, are generally not restricted to potable water, since parasites, viruses and bacteria that may be present are killed during the processing, leaving the product safe for consumption.
Primary crops, in contrast, are those which come directly from the land and are often consumed without having undergone any processing apart from cleaning (lettuce, carrots, blueberries and strawberries, for example). For these crops, safety regulations stipulate that only potable water may be used for postharvest activities such as washing, transporting produce, cooling, applying coatings, and handwashing, since viruses, bacteria, and other toxins could easily be transmitted directly to the humans who consume them after this point. Even the equipment used in these steps must be cleaned with potable water. Unfortunately, it’s not uncommon to hear news reports of outbreaks of this type that seem to be most associated with leafy greens, but also to various root, vine and stalk vegetables, fruits and berries, nuts, and even sprouts.
The use of potable water during these steps is important because the practice of washing fruits and vegetables, especially leafy greens, doesn’t remove all germs. Germs can stick to the surface of the vegetable or even get inside it, and if the vegetable is consumed raw, it has the potential to cause illness. For these crops, then, only potable water is acceptable. Potable water has been tested (and treated, if necessary) to be free of such microorganisms, so consuming fresh produce that’s been handled correctly is presumed safe.
Keeping Potable Water Potable
When potable water is required for any kind of industrial, livestock, or agricultural activity, careful sourcing isn’t the end of the mission. Just as it wouldn’t make sense to pay to truck in a tanker full of clean tap water, only to dump in a few gallons of toxins, it doesn’t make sense to expose your water supply to contamination during transportation, storage, and application.
Geotextile liners, some plastics, glass and other materials are tested and graded according to their ability to store and interact with water without leaching harmful chemicals over time. Any device or material that comes into contact with potable water should be NSF/ANSI certified, including liners, faucets, pipes, valves, sealants, etc. The highest level of certification, awarded only for materials safe for potable water, is ANSI 61. Liners that are ANSI 61 certified are tested over long periods of time to ensure that even the eventual breakdown of the material due to UV exposure doesn’t change what’s released into the water.
We all understand that marketing terminology can sometimes be misleading. Be aware that it’s not enough to choose a liner that the manufacturer claims to be safe for food use. Some plastic materials contain chemical additives like phthalates to make them flexible and easy to work with, but they can leach into the water over time, and long-term exposure to phthalates have been implicated in numerous health problems including damage to the liver, kidneys, lungs, and reproductive system. Chemicals, heavy metals and other contaminants like microorganisms don’t just sink to the bottom of your storage container or evaporate -- they’re distributed to your crops and absorbed through the roots and can directly influence the health of the people you feed.
You’ve undoubtedly put a lot of money and energy into obtaining and testing high quality water for your agricultural needs. Don’t undercut yourself by storing it where it can be re-contaminated, either by nature or by man. Check out BTL Liners instead. We offer a range of products that are fully ANSI-61 certified to protect your investment.
