Water Use Stewardship in the Food System

The use of natural resources such as water in food production is a sustainability issue that continues to be on the radar of many farmers, food processors and consumers. In many regions of the world, water scarcity is on the rise as the demand for food production increases.

In 2019, the U.S. Department of Agriculture (USDA) reported that agriculture remained a major user of fresh water in the United States and that the 2017 Census of Agriculture reported that there is a total of 58 million acres of irrigated cropland in the U.S. USDA goes onto note that sustainable irrigation and water use practices are at the core of managing food production efficiency and responsible natural resource usage. What do these water saving practices in our food system entail? Let’s take a look at farm and food processing plant activities to learn more.

Water and Farming Do Mix

Of course, growing crops needs a notable amount of water to ensure productivity, but farmers aim not to waste any. Part of proper crop-growing and wise water use is linked to advances in irrigation techniques, which allow water to move from one location to the next. Water not absorbed into the ground for crops can collect at the low end of furrows, border strips and basins. This wastewater is also referred to as irrigation tailwater. A certain amount of tailwater runoff is needed to ensure adequate penetration of water and irrigation efficiency, but the additional tailwater can be safely reused. Another source of agricultural wastewater, albeit a bit more indirect, is runoff from centralized plant facilities processing crops harvested from the field.

Both of these sources of wastewater can be reclaimed and used on neighboring farms or on the farm where it was generated. Wastewater that collects at the low end of furrows can be used for the irrigation of fields at lower elevations without filtration or purification treatments and without pumping. With pumps and collection systems, the runoff can be stored in ponds for later reuse as needed.

Agricultural wastewater from processing plants typically contains a significant amount of organic matter, which will need to be diligently filtered out and/or inactivated to ensure the safe reuse of the water. Some water cannot be reused and must be treated for disposal—the Environmental Protection Agency sets strict criteria for discharge of wastewaters from industries. In the select cases where wastewater can be used for soil conditioning and irrigation, the water can help farmers improve the soil’s organic content, moisture-holding capacity, nutrient content and productivity. However, application of these wastewaters to the fields must be done with great care to avoid runoff and groundwater contamination.

Process, Save Water, Repeat

Further from the farm, many food and beverage production plants reuse process wastewater onsite while still maintaining safety and quality. The majority of wastewater in food production facilities is used in non-food contact contexts, such as irrigation of landscaping, truck washing, cooling towers and warehouse floor washing. However, in some cases water can be reused in boilers, evaporators or chillers. Depending on how the water will be reused, it may require processing steps in order to remain safe.

For beverage producers including breweries, dairies, and soft drink, juice or bottled water plants, there are more opportunities to safely reuse process waters, simply because these products are made mostly of water. Both food and beverage companies employ water use monitoring systems (such as flow meters and leak detection systems) and can calculate their water-use ratio (the amount of water to produce a product versus the water contained in the final product) to see where the water is going in the plant and to minimize any waste.

No Waste, No Foul

Employing these methods on the farm and in manufacturing facilities can have a big impact on conserving natural resources in our food supply chain. Not only do these reuse strategies save water, but they also conserve energy, which water processing companies use to purify and pump water to farms and facilities, and also to treat sewage.

They add up to good things for a reliable food supply, and great things for the environment. We can all raise a glass (of water) to that!