Winter snow could help recharge the Colorado River. But what if it doesn’t?

When the snows come to the mountains of Colorado, it’s good news for
skiers but also the first step to recharging the Colorado River.

But this winter’s precipitation outlook is unclear, and how it
unfolds will have an outsized impact on the next few years of management
of the river, which supplies water to tens of millions of people from
Wyoming to Mexico and gets most of that water from high-altitude snow,
two-thirds of which falls in Colorado.

A wet winter
last year created more space for long-term negotiations about how to
share river, but policy analysts say things could quickly turn in the
wrong direction if snowfall is low in the coming months.

“Rivers are a great example of how we’re all connected,” said James
Dilzell, director of the nonprofit Eagle River Watershed Council, as he
stood on the banks of Homestake Creek in Eagle County, Colorado, this
fall. “It’s not a totally separate place to be here in the headwaters in
Eagle County versus somewhere in Utah or Phoenix. We’re all in this
together, and it’s all the same water.

“It’s amazing to think of the journey,” he said, noting that what
happens to the rivers and streams near the resort town of Vail has
far-reaching impacts.

The Eagle River watershed, mostly comprised of tranquil mountain
creeks that surge with spring snowmelt, contributes about 3% of all the
Colorado River’s water. Soon, feet of snow should blow into Eagle County
valleys and wetlands, giving water managers a clearer picture of how
the river and the seven states that use it – Arizona, Colorado,
California, Nevada, Utah, New Mexico – will fare in the near future.

But right now, that picture is far from clear.

‘It’s a big crapshoot’

Even in an age with complex forecasting methods and a sprawling network of weather data sensors, accurate predictions for a winter’s worth of snow are hard to come by.

“I can tell you that it’s anyone’s guess,” said Becky Bolinger,
Colorado’s assistant state climatologist. “At the very beginning of the
water year, it’s a big crapshoot. We don’t have a lot to go on.”

Winter weather in the Colorado River Basin this year will be largely
dictated by El Niño – a phenomenon where warmer-than-usual water in the
Pacific Ocean changes temperature and precipitation patterns over the
Western U.S.

Typically, El Niño brings warmer, drier weather to northern parts of
the West, and cooler, wetter weather to southern parts. Frustratingly
for forecasters in the Colorado River Basin, the dividing line between
those weather patterns falls in and around Colorado.

In October, the three-month forecast from the National Weather
Service’s Climate Prediction Center showed the entire Colorado River
Basin equally likely to have above, below or near average precipitation
for November, December and January. By November, the outlook for January, February and March was calling for slightly above-average precipitation for most of the Rocky Mountains.

How much of that water ends up in reservoirs will not come into focus
until January, though decisive data isn’t typically available until
late May or early June, when streamflows reach their peak.

Forecasters do know one thing for certain: Last winter’s heavy snows
left an impact. Snow totals broke records in Colorado, soaking the
ground and setting up good conditions for runoff in spring 2024. That’s
because dry ground acts like a sponge, soaking up and holding on to precipitation.

But a snowy winter and rainy summer like the last help fill up that
sponge, making it easier for the spring melt to run off into streams,
rivers and reservoirs. So this winter’s snow is less likely to get lost
on its way to the river.

“Even though we’re kind of at the beginning of the race, we’re not
starting further back from the starting line than we should,” Bolinger
said.

Watching snow from the desert

As the Colorado River has been stretched by drought and rising
demand, soil moisture data has come under greater scrutiny, as water
managers look for increasingly granular, precise data about water
availability.

Data about snow, soil and streamflow is important far from the mountains.

Phoenix, for example, is hundreds of miles from the Rockies, gets 40%
of its water from the Colorado River. So the city’s water managers
track Colorado weather closely.

“We watch it throughout the winter,” said Cynthia Campbell, a water
adviser for Phoenix. “October 1 comes around and it’s game on. We watch
the snow patterns, we cheer when there’s big snowfall in the Rockies.”

Water managers in other major cities like Los Angeles, San Diego, Las
Vegas and Albuquerque also keep a close eye on that faraway snow and
how it affects the nation’s two largest reservoirs, Lake Powell and Lake
Mead.

Powell’s levels are largely dependent on precipitation from the past few winters. Lately, they’ve dropped to record lows,
imperiling a major dam and hydropower system. Lake Mead, which stores
water for use in Phoenix and other Southwestern cities, has also hit
record lows after more than two decades of drought and steady demand.
With both major reservoirs on the brink, each winter has become more
important.

“We have, even over the past decade or two, really seen how this
system can seemingly turn on a dime,” Campbell said. “Especially when
it’s at lower levels.”

‘We can’t be naive’

In recent years, water managers throughout the Southwest have been
operating in a kind of emergency mode, assembling a patchwork of
temporary conservation deals to keep water in Lake Powell and Lake Mead
and stave off damage to major dams.

But even under intense federal pressure, the seven states that rely
on the Colorado River have not been able to agree on longer-term
guidelines that would substantially cut back demand. River experts say
last winter’s boost lifted some weight off negotiators’ shoulders,
letting them finally focus on the long term.

Arizona, California and Nevada say their recent short-term
conservation deal has eased some of the pressure, but policy analysts
say a wet 2023
did most of the heavy lifting there. Talks are underway to shape a new
set of guidelines for how the river is shared before the current rules
expire in 2026.

Kyle Roerink, director of the nonprofit Great Basin Water Network,
said last year’s wet winter could allow for those long-term talks, but
warns that the perilous state of Lakes Powell and Mead means dry winters
could again force new short-term conservation deals.

“Two or three dry years will bring us back to the brink,” he said.
“There’s no doubt about it. So we can’t be naive. We can’t take our foot
off the gas.”

Negotiators face an uphill battle to agree on new guidelines that
work for everyone, including the 30 federally recognized tribes that use
the river’s water and have called for a greater voice
in shaping its future. Big cities, farms, conservationists, the federal
government and outdoor groups are also advocating for policies that
protect their interests.

At the center of the talks is the need to reduce demand on the
Colorado River at a time when climate change is steadily reducing
supply. Roerink said that will take forward thinking.

“I am just hoping, praying, crossing my fingers that decision makers
on the inside this time will not take the easy route,” he said. “They’re
going to do the hard work, and we’re going to have better long-term
outcomes to avoid being where we were the past couple of years.”