The Middle Rio Grande Conservancy District opened its headgates this week to test infrastructure in advance of irrigation season.

The opening of the gates on Monday allowed the MRGCD to flush the canals and ensure that everything is in working order when it comes time to deliver the water to irrigators.

The official start of irrigation season depends on various factors such as weather, available water, soil conditions and other water users such as Pueblos and the Lower Rio Grande in Texas and south of Elephant Butte.

The MRGCD anticipates water will be available on a limited basis starting in mid-March for irrigators, though the northern part of the system generally has limited demand for water until late March or early April.

Most irrigators order water deliveries in April, leading to a surge in demand.

Matt Martinez, water distribution division manager for MRGCD, said that water users should be conservative in their water use, as the availability of water throughout the season depends on various factors.

In recent years, the MRGCD has had to warn irrigators that water deliveries could end in the middle of the summer due to lack of water when flows in the river dwindled.

Martinez joined crews at the Angostura Diversion Dam in Algodones to open the headgates there.

One reason for the dwindling Rio Grande flows the past few summers has been the lack of storage in El Vado Reservoir due to its closure for repairs. Once again, the MRGCD is looking at an irrigation season without El Vado Reservoir to store water. 

While the initial spring irrigation season should have enough water for the MRGCD customers, that could change quickly during the dry summer months since the district won’t be able to release water from El Vado.

The federal Bureau of Reclamation is working on safety modifications at the dam located on the Rio Chama in northern New Mexico. While those modifications are underway, the MRGCD cannot use it to help meet demand.

The district receives an annual allotment of water from the Colorado River Basin through the San Juan-Chama Project, which takes water from above Navajo Dam and routes it through a series of dams and tunnels to the Rio Grande Basin.

Water managers are watching the snowpack as that will help determine how much water is available through runoff; however, if the weather warms too quickly it can lead to increased rates of snow melting as well as increased evaporation. As the climate changes, those scenarios have become increasingly common, meaning that even in years with good snowpack the runoff season can be shorter and with lower flows.

That means water managers like the MRGCD must now try to find ways to maximize the supplies.

One way that MRGCD is doing this is by reducing how much water is lost to the soil and vegetation along the ditches. That involves lining ditches with concrete.

Martinez said lining the ditches helps reduce seepage and also saves money on maintenance costs.

When the MRGCD opened the headgates to a section of canal in Socorro, water flowed into the newly-lined concrete ditch bed for the first time.

The MRGCD boasts 170 miles of main canals that supply irrigators with water. Alicia Lopez, engineering and mapping manager for MRGCD, said in an email response to questions that, while sections of MRGCD’s existing main canal system have been lined and reinforced, those linings have now aged to the point that they need to be replaced. Lopez said the MRGCD does not know how many miles in total have been lined.

“Our financial leadership has been active in pursuing grants to fund these projects. We’re really excited about it,” Martinez said.

In 2023, the district turned to the state for assistance and, utilizing the first of what Lopez described as a series of grant funding, it was able to line the first mile of the Socorro Main Canal. This canal is important because it serves as an artery to all the irrigated lands in Socorro County, Lopez said.

The MRGCD decided the best way to line that mile of canal was to use rebar reinforced with sprayed concrete, she said.

Martinez said the MRGCD will be able to study the impacts of lining the canal and determine how much water is saved through that effort.

Lopez said this work won’t stop with the mile of ditch in Socorro. Instead, the MRGCD has applied for funding through the Water Trust Board and hopes to use that money to continue lining the channel, starting with extending the lined section of canal in Socorro. That work will likely begin in November.

“Eventually, lining all of MRGCD’s main canal system will improve system flexibility to efficiently deliver all available irrigation supply,” Lopez said.