Copyright © 2013 Albuquerque Journal
BERNARDO – Tyson Hatch looked down shortly after daylight Monday into water 17 feet deep swirling down the normally bone-dry Rio Puerco beneath the old N.M. 60 bridge.
Seventeen feet was a rough number. The Puerco had been flooding all night, flows not seen since September 1972. Around 5 a.m., the water blew out the U.S. Geological Survey gauge that measures flows just upstream from the old steel girder bridge. As the sun rose over the flooded valley, Hatch, a USGS technician, was busy rolling out a temporary instrument so people downstream would know how much water was coming.
Flanked by salt cedar, the Rio Puerco is usually a less-than-memorable dry arroyo, a flash in the corner of your eye as you cross it on I-25 in northern Socorro County. Sprawling across New Mexico’s normally arid high country from the Zuni Mountains to Cuba, the Rio Puerco watershed is big, but mostly quiet.
But in a scene repeated in watersheds across New Mexico over the last two weeks, the Puerco had turned into a different thing entirely in the face of a storm that was, in many places and by many measures, unprecedented since New Mexicans began keeping weather records more than a century ago.
The water that wiped out Hatch’s gauge Monday morning began in the high country of west-central New Mexico, slamming Bluewater Village northwest of Grants on the way past, damaging an estimated 50 homes as mud and debris topped the banks of the Rio San Jose.
“We’ve probably filled 15,000 to 20,000 sandbags in the past couple of days,” Tony Mace, Cibola County’s undersheriff, estimated last Monday. “We’re trying to keep the water in the ditches and keep it out of the sewage system.”
Floodwater began receding by Wednesday, leaving behind at least $1 million in damage to Cibola County roads, bridges and culverts, estimated Cibola County Emergency Manager Tony Boyd.
“Now we’re left with the mud and the cleanup and doing the damage assessments,” Boyd said Friday.
Downstream, where the Puerco finally dumps its load into the Rio Grande, Kerry Jones, a National Weather Service warning coordination meteorologist, stood on the Rio Puerco Bridge in the pre-dawn hours Monday morning, listening to the river swirl through trees that under normal conditions are high up the river’s banks. Nearby, a command post of nervous county emergency managers began evacuating the little cluster of a dozen houses known as San Francisco, one of the riverside villages scattered along the Rio Grande Valley south of Albuquerque. Slowly, the water lapped up into the valley homes.
It was a scene repeated across New Mexico, sometimes with slowly rising water that swamped San Francisco, and sometimes in the form of dramatic flash floods like the wall of mud and coal that washed down into Madrid northeast of Albuquerque.
By the time the storm began tapering off late last week, flood damage had been reported in 25 of New Mexico’s 33 counties.
At the offices of the U.S. Army Corps of Engineers, flood control operations manager Ryan Gronewold had known for more than a week that trouble was possible. The early warning came from the National Weather Service on Sept. 6 as forecasters watched the slowly forming pattern of what has historically signalled a worst-case scenario for New Mexico.
Summer thunderstorms are often trouble, as big storm cells swamp watersheds. But those generally only hit a single area, causing flooding in one or two counties at a time. Spring floods are also a possibility in years with massive snowpacks, but those can be anticipated months ahead of time as warm spring weather begins melting winter snow.
But some of the state’s most notorious floods have been from storms like this. Late in the summer rainy season, on top of soil already wet from monsoon storms, a slug of atmospheric moisture flowing into New Mexico from a tropical storm remnant dumps widespread precipitation across the state. The storms can happen at any time between June and October, but the risk peaks in September, according to research by University of New Mexico scientist David Gutzler and his colleagues.
That is the possibility federal forecasters began to see on Sept. 6. They were tracking tropical storm Lorena, pumping moisture into the atmosphere off the southern tip of Baja. To the north, weather patterns were setting up to our east and west that amounted to a giant atmospheric funnel to channel all that moisture straight up through New Mexico like a firehose – a supercharged version of the state’s summer monsoon storms.
“We knew that we were going to need to be on the lookout,” Gronewold said.
The forecast turned out to be on the money. By the time the storm was over, there were record rainfall numbers all over New Mexico. And these were not one-day records, but the product of sustained rainfall over a very wet week in many places.
Los Alamos received 7.05 inches beginning Sept. 10, the highest six-day total since 1902. Albuquerque’s total of 3.14 inches was also a six-day, all-time high, with records going back to 1891, according to the National Weather Service. Las Vegas’s 6.24 inches was the highest six-day total since 1941.
“That’s true for a lot of areas,” the Weather Service’s Jones said.
Commissioners in at least nine New Mexico counties issued disaster declarations this week, but the list is likely to grow, state officials said.
About 25 of the state’s 33 counties have reported some damage after a week of flooding, said Estevan Lujan, spokesman the New Mexico Department of Homeland Security and Emergency Management.
No severe flood damage has been reported since late Wednesday, when heavy rainfall in Rio Arriba County flooded an estimated seven homes in the Chamita area north of Española, Lujan said.
Gov. Susana Martinez drafted a letter this week requesting a federal disaster declaration that would make the state eligible for FEMA funding to pay for public infrastructure, such as roads and bridges.
FEMA officials are expected to continue making preliminary damage assessments through next week to determine the extent of damage in New Mexico.
A FEMA official said this week that federal funding will pay for repairs to public infrastructure, such as roads and bridges, but will not provide individual assistance to people whose homes were damaged by flooding.
No statewide figures were available at the end of last week, but some counties had preliminary tallies. In San Miguel County, the figure is between $6 million and $7 million. That doesn’t include the city of Las Vegas, which had infrastructure and water treatment facilities damaged. In Eddy County, Emergency Manager Joel Arnwine said damage to road and other public facilities there are estimated at up to $1.8 million. In Cibola County, the figure was about $1 million, and in Los Alamos, officials estimated $5 million in damage with millions more at Los Alamos National Laboratory. The U.S. Department of Transportation estimated $9 million to the state’s roads and bridges.
By the time it was over, the rain had provided significant relief for New Mexico’s drought. But coming on the heels of three very dry years, many parts of the state are still in a deep precipitation hole. This is already the wettest September on record, with 3.39 inches through Friday. According to Jones. But despite that, Albuquerque remains 9 inches behind average over the last 36 months, he said.
As the floodwaters receded and the water supply calculations began last week, the Pecos River in eastern New Mexico came out the big winner. Pecos reservoir storage for area farmers went from 11 percent full to 92 percent in a space of less than two weeks.
While there were flooding problems in Pecos Valley communities, the boost to the water supply was a blessing in the drought-plagued communities, according to Aron Balok, head of the Pecos Valley Artesian Conservancy District, the valley’s largest farm water management agency.
“It got pretty close to my house,” Balok said of the arroyo flood flows, “and I still didn’t say I wished it would stop.”
Carlsbad area farmers, after having almost no water this year, are already guaranteed a good water supply for their crops in 2014, just based on the water from this month’s storm, according to Dudley Jones of the Carlsbad Irrigation District.
The Pecos was the big winner in large part because, with less acreage irrigated with river water and smaller dams, the state’s long-term water supply deficit was easier to make up. In the state’s two larger river systems, the Rio Grande and San Juan basins, the storm was helpful in water supply terms, but in a much more modest way.
The Rio Grande’s water supply reservoirs, especially Elephant Butte and Caballo in the southern part of the state, which are far larger and therefore more difficult to fill with a single storm, went from 7 percent to 11 percent of capacity. Elephant Butte, the Rio Grande’s largest water storage reservoir, which holds 2 million acre feet of water, gained more than 50,000 acre feet of water in the storm, rising from 4.4 percent to 5.9 percent full.
The problem on the Rio Grande, according to New Mexico State University hydrologist Phil King, is that a summer rainstorm, even one as large as this one, cannot begin to make up for the shortfall caused by years of low winter snowpacks.
“Monsoons don’t get us out of drought,” King said. “We get a few tens of thousands of acre-feet from a good monsoon, but over a million from a good spring runoff season.”