Ultimately, the truth is that farmers who depend on irrigation face a future with increasingly limited water supplies coupled with increasing demand from competitors. In an progressively more pressured environment, fundamental changes need to be carefully weighed so that irrigated agriculture can be reasonably sustained well into the future. Questions of where irrigation is used, which crops should be irrigated and what methods are most appropriate cannot be answered on a permanent basis as climate conditions continue to change. Farmers will need to focus on maintaining a realistic, flexible and responsive stance.
The Need for Drought Resiliency
The ability of farmers to respond and adapt to drought and variations in water supply is ultimately the measure of irrigated farming’s resilience. Complications associated with continued changes, including changing temperatures, precipitation, and snow melt patterns could potentially alter or even limit the role that irrigation ultimately plays in US agriculture. Creating the necessary resilience in water use isn’t simple or easy, and so far, our nation’s success in creating a sustainable water-use model has been insufficient.
In scenarios repeated across the country, when farmers have been faced with surface water shortages or restrictions due to drought, they’ve turned to groundwater and continued their normal irrigation patterns. It’s not clear whether anyone seriously considered that most groundwater is replenished very slowly and so should not be treated as an unlimited, renewable source. Collapsed aquifers, land subsidence, groundwater contamination and even saltwater intrusion in some critical aquifers were the result of unlimited use. This damage to aquifers is permanent and could significantly affect those regions as they attempt to move forward in the new normal.
The new ground shift in irrigation philosophy and practice must have a clear effect downstream for the industry’s sacrifices to be worthwhile, so it’s important that water savings are not immediately churned back into agriculture by expanding irrigated acreage or moving to thirstier crops. In current levels of scarcity, water savings should be reflected in rising river levels. As these levels are restored, ecosystems within and alongside rivers and lakes should recover. This recovery will ultimately allow critical functions of riparian and other ecosystems to be reestablished, which help filter and decontaminate surface waters. The value of those effects and cascading benefits to the environment should not be underestimated.
A Clear and Present Danger
It’s easy to focus on California’s Central Valley when pointing fingers, but it’s a valuable lesson in the dangers of unsustainable agricultural practices. To appreciate the importance of the lesson, keep in mind that Central Valley is responsible for more than a third of the country’s vegetables and two thirds of its fruit and nuts. If Central Valley were to collapse as an agricultural powerhouse due to sustained water crises, how quickly could the nation replace the volume and variety of food those farmers supply? Certainly not within a single season.
Unfortunately, California’s current agricultural practices are clearly unsustainable. As weather patterns change, extreme temperatures and devastating droughts are already forcing farmers to leave vast expanses of arable land untended, unable to sustain even cover crops to protect soil from wind erosion. Whenever possible, many of these farmers devote their remaining land and resources to growing drought resistant crops and established perennials that require relatively little water. It’s discouraging, then, when other farmers choose to focus on high value crops that require intense irrigation. Almond trees have been the focus of much public ire for that reason.
Very large corporation-owned farms are often viewed as culpable in those kinds of practices that focus on immediate financial gain as opposed to long-term care and stewardship of the land.
For that reason, some experts advocate for decentralized farming in favor of small and medium scale farms, who are focused on sustainability and eschew damaging practices like monocropping. This would require making some fundamental changes to Federal policies, however, which currently are skewed to support large industrial operations.
Some of those same experts argue that agricultural activity in the state should be cut back to a level that’s in line with available water resources. At current levels, California’s agricultural industry is clearly unsustainable and it’s unwise to depend on it for so much of our food.
Shifting Priorities, Changing Practices
Other regions must also adapt to an increasingly limited water supply. Some possible strategies may include relatively easy practices like shifting irrigated areas, maximizing irrigation efficiency by choosing the optimal irrigation system and taking advantage of available upgrades like those that allow for precise application and detailed monitoring of soil conditions.
In some cases, farmers may need to contemplate the use of alternative sources of irrigation water such as recycled or reclaimed water. This option should be carefully studied - much of the public opposes consuming food that has been exposed to recycled water, but animal silage may be acceptable. In addition, the provenance of treated water should be considered, since many wastewater plants are neither required nor capable of removing dangerous contaminants like radium.
