Farmers in central New Mexico have long relied on the nourishing waters of the Rio Grande to sustain their crops through the sweltering summer growing season. Water from the Rio Grande is delivered to farmers through a complex network of acequias and ditches, some of which were created centuries ago by the state’s Indigenous and Spanish inhabitants. In the Middle Rio Grande, these irrigation systems are now managed by the Middle Rio Grande Conservancy District (MRGCD). Farmers must have a water right to connect to MRGCD systems, though the amount of water that they receive from the MRGCD is dependent on water availability in the Rio Grande. Water allocations are tricky – the MRGCD must attempt to meet farmer’s needs while simultaneously supporting river ecosystems and complying with interstate compacts.

New Mexico is in the midst of what experts are calling “the driest 22-yr period since at least 800 AD”. This megadrought is almost certainly linked to climate change and has significantly reduced the average amount of snowpack feeding the Rio Grande and other western rivers.The MRGCD forecasts that the 2022 irrigation season will be severely limited by low water availability and is “warning all irrigators to expect significant changes to irrigation delivery.”

To limit the economic impact of reduced water provision and promote conservation, the MRGCD is encouraging irrigators to enroll in its newly expanded Emergency Fallowing Program. Fallowing a field means that it is not planted or irrigated, so the water that would have been used to grow crops is left in the river. If approved for this program, irrigators will receive $425 from the MRGCD for every acre of land that they fallow. The 2022 acreage cap for this program is 14,000 acres, which will cost the MRGCD approximately 6 million dollars. The majority of the money to fund this program was appropriated to the MRGCD during the 2022 state legislative session. Irrigators enrolled in the Emergency Fallowing Program are not at risk of losing their water right for non-use, as may otherwise be the case if they do not irrigate their land.

Fallowing programs have successfully reduced overall water consumption in water-stressed irrigation districts around the west. One of the most successful programs implemented to date was implemented in California’s Imperial Valley, which has partnered with municipal providers in Los Angeles to compensate farmers up to $175 per acre-foot of water saved. The Imperial Valley Fallowing Program is generally considered successful because its competitive pricing made fallowing an attractive option and because strict rules ensured that fallowed land was rotated to prevent soil degradation.

Average consumptive use in the Middle Rio Grande is approximately 3-acre feet per acre over a growing season, so Middle Rio Grande irrigators would make around $525 per acre if paid at Imperial Valley rates. While the price paid to Middle Rio Grande farmers is lower than the price paid to  Imperial Valley farmers, the MRGCD fallowing program may still be an attractive economic option because the crops grown in the Middle Rio Grande generally bring in less money than the high dollar crops grown in the Imperial Valley. Alfalfa is the most commonly grown crop in New Mexico and most alfalfa grown supplies the state’s beef industry. The New Mexico State Agricultural Extension Office estimates that an acre of alfalfa grown in New Mexico sold for $273 to $396 in 2019. This is a substantially lower amount than the same land would bring in if fallowed and is an especially attractive option because farmers do not have to invest time and resources into growing or harvesting the crop.

Despite the water savings associated with fallowing, it is typically not seen as a long-term solution for significant water shortages. Soil that is not productive for multiple seasons will typically result in low soil moisture and soil nutrient depletions. This will make it more difficult to grow productive crops in the future and may require planting cover crops to restore soil health. To prevent abuse of fallowing incentives and soil degradation, previous MRGCD fallowing programs have prevented irrigators from fallowing a tract of land multiple years in a row, though the 2022 program has waived this stipulation because of the projected severity of this year’s water shortage.

Assuming the MRGCD successfully enrolls all 14,000 acres of approved land in the Emergency Fallowing Program and that crops in the MRGCD consume 3 acre-feet of water per acre, total water use in the MRGCD will be reduced by approximately 42,000 acre-feet. While these savings are not nearly enough to cover the state’s outstanding 125,000 acre-foot debt to Texas under the Rio Grande compact, they will almost certainly support farmers with an alternative source of income, help the state meet its long-term contract obligations, and support the ecosystems that surround the Rio Grande. In the words of Casey Ish, the MRGCD’s conservation program coordinator, “Programs such as the Emergency Fallowing and Environmental Water Leasing Program (EF-EWLP) provide the District with a ‘lever’ that can be raised and lowered to adjust our demand on the river. When the District can meet these different demands (ecosystem, irrigation, and compact requirements), I believe you have a sustainable system.”

-Posted by Nic