By Scott Manning
Second in a series
Given the ongoing drought and expected water shortages from the Rio Grande due to climate change, well water is being eyed in Corrales and elsewhere —even though the aquifers here are sustainably replenished only by river flow and snow in the Sandias. The drought has impacted the past two growing seasons for farmers here. Some Corrales farmers rely on available surface water to irrigate their fields. This past winter, the Middle Rio Grande Conservancy District (MRGCD) anticipated further droughts and advised farmers to reduce their farming operations because access to irrigation water for the duration of summer 2021 was not guaranteed.
These water restrictions are difficult for farmers, but there is an alternative: pumping well water from the aquifer below the Corrales Valley. According to Mike Hamman, chief engineer and CEO of the Conservancy District, his office has not encountered many farmers who have applied to pump well water rather than irrigation with surface water. In contrast, more farmers use well water in the Elephant Butte Irrigation District.
Hamman suggests that certain obstacles may stand in the way of farmers adopting well water pumping. First, the farmer would need well water rights. In 1956, the New Mexico Office of the State Engineer “declared†the Rio Grande Underground Water Basin, and closed the aquifer to new wells for large-scale farming. This policy limited large farm wells but allowed for domestic well drilling.
Some longtime farmers in Corrales who began farming with groundwater before 1956 have groundwater rights which allow for well water pumping. But other farmers would need to obtain groundwater rights before they could begin pumping. Second, a farmer switching to groundwater would likely have to invest in additional water infrastructure and technologies like a drip irrigation system. This infrastructure can be costly to implement compared to the cheap and easy use of surface irrigation water.
Despite these obstacles, some smaller farmers who grow high-value crops like fruits and vegetables or delicate plants have embraced groundwater pumping. One such farmer is Courtenay Koontz, owner of the tree nursery Trees of Corrales. For Koontz, the adoption of a groundwater-fed drip irrigation system was the best choice for his business. Koontz explains that the physical constraints of his farming operation require a drip system: plants in the nursery are planted in containers such that they are elevated above ground. A simple surface water irrigation scheme that floods a field would not work to water these plants. Koontz also needs consistent water delivery and quality to ensure that the plants in the nursery thrive. Drip irrigation delivers clean aquifer water to the trees in a set amount on a routine basis.
In contrast, surface water irrigation leads to irregular watering cycles in which a field is flooded and soaked with water and then dried. Additionally, the quality of surface irrigation water is subject to environmental and human factors beyond the control of the farmer: surface water may contain pesticides, debris, or seeds from upstream plants. Koontz wants to limit this water variability.
Koontz says he prefers to use groundwater over surface water, and he would convert all of his farming operations to groundwater if he had sufficient water rights. Koontz owns groundwater rights, and his business is subject to oversight by the Office of the State Engineer. The State Engineer limits the volume of groundwater Trees of Corrales can use each month; Koontz must submit water records demonstrating his compliance with the agreement. And should the water authorities suspect water overuse, they can directly verify it.
This kind of agreement between farmers and the State Engineer aims to give farmers access to groundwater and ensure responsible use of the aquifer. Water authorities across the state are monitoring water supplies because New Mexico communities and farmers rely on this precious resource. Congresswoman Melanie Stansbury was reported earlier this month warning that “New Mexico is looking at potentially losing almost all of its snowpack in the next 50 years.â€
Stansbury said the challenge is how to prepare for that while preserving “cultural practices, agriculture and survival of our communities.â€
If the aquifer under Corrales is unlikely to be adequately recharged by Colorado snowmelt in the future due to climate change, there’s another recharge method already under way.