Monsoon saves irrigation season – for now
Runoff from recent rains has filled irrigation ditches this past week, but no one knows for sure how long surface water will be available for local farms.
In a normal year, irrigation ditches are filled using water from upstream storage reservoirs and run off, but this year is not normal, according to Johnny Ray Mounyo, Socorro Division Manager with the Middle Rio Grande Conservancy District.
“We ran out of storage water on August 15,” Mounyo said. “We are short of water, and we tried to conserve storage water and make it last as long as we could. Last year, we ran out of stored water on September 1. It’s been a long time since we have run out of storage water this early.”
Since Aug. 15, runoff from rains up north, primarily from the Puerco and Salado watersheds that drain into the Rio Grande between Belen and Socorro, has filled the river, and the MRGCD is diverting all of that runoff into the Socorro irrigation system.
“Some people think that water’s too dirty,” he said. “But it’s wet.”
But with the monsoon kicking up again, more arroyos upstream are watering the Rio Grande.
“It’s good right now. We’ve got pretty good water,” Mounyo said. “We’ve got all the water we can run in the main canal. I don’t know how long it will last — it just depends on the rains.”
Will the monsoon last?
Even though this summer has seemed dry, this year’s monsoon season has been better than last year’s, according to National Weather Service meteorologist Kerry Jones in Albuquerque.
The NWS maintains five weather stations in Socorro County, Jones said. The rainfall measurements show that this July has been anywhere from 85 percent of normal at Socorro Airport to 47 percent of normal at the Bosque del Apache refuge. So far this August, Socorro County is showing about 50 to 87 percent of normal rainfall, according to NWS data. Last year’s monsoon was half of normal or less for most of the state,
Last year, the January through July rainfall was the driest on record since 1897 at 42 percent of normal statewide. January through July of this year was the eighth driest on record, but it takes only a storm or two to change the statistics, Jones said.
Predicting rainfall for specific areas is tricky.
“The average thunderstorm is 10 to 15 miles across, so you can have heavy rain at one location and 20 miles away, much less,” he said.
So far, the monsoon has been favorable in the northern sections of Socorro County and the Puerco and Salado watersheds this summer.
“The area around Cuba in the Puerco watershed has had 150 percent of normal monsoon moisture this year,” Jones said. NWS maps show the same above-normal rainfall in northern Socorro County in August.
Jones said monsoon activity will taper off this weekend, but the county can look forward to three to four weeks of thunderstorm activity. After that, the monsoon pattern gradually breaks down.
Fall and winter may be wet
“We usually have a secondary peak of severe weather with hail and rain in mid-September to early October,” Jones said. “The big Socorro hailstorm happened on October 4.”
Next year’s irrigation supply depends a lot on this winter’s snow pack, and Jones said that it’s shaping up to be a wetter winter.
“The last two winters we were in a La Niña pattern, which usually means dry conditions. But this winter, it looks like it will be an El Niño, which is favorable for more cool season precipitation, although it may be brief and not as reliable a forecast as it would be for a La Niña,” Jones said.
Farmers mostly happy
Local farmer Linda Rosales agrees things are better this week since the rains have started.
“We have had to wait 20 to 25 days to water, but we have water now. This rain last week was our first big rain, and everything’s full,” she said.
Linda and her husband Mario farm about 300 acres in chile, alfalfa, and Sudan grass, mainly in the Lemitar area. The lack of reliable irrigation water has hurt their crops.
“In the heat, alfalfa has matured faster,” she said. “We’ve had to wait longer for water, so there might be one less cutting than usual, depending on water in the ditches. Our chile has matured faster, too, but the pods are smaller because of the lack of water.”
Next year, they plan to lease fields with water supplied by irrigation wells.
“People with wells will have a normal crop this year,” she said.