The white “bathtub ring” around Lake Mead near Boulder City, Nevada, on July 1 shows how much the water level has dropped as the drought in the US West worsens.
David McNew/Getty Images

Following a July that scientists say was the hottest in the 150 years that records have been kept, the US government has declared a water shortage for the Colorado River Basin that supplies countless farmers and major population centers like Phoenix, Las Vegas and Los Angeles.

The shortage means less water for Arizona, Nevada, California and Mexico and will inevitably hit farmers hard after a hot, dry summer that has seen records broken across the western edge of the continent.

“This is the first time a Tier One water shortage has been declared in the Colorado River Basin, but climate change and aridification across the Southwest mean it won’t be the last,” the Water for Arizona Coalition said in a statement.

The historic declaration follows a week in which the massive Dixie Fire in California the latest sobering report on the state of the climate served as exclamation points for a planet on red alert.

“July 2021 outdid itself as the hottest July and month ever recorded. This new record adds to the disturbing and disruptive path that climate change has set for the globe,” says NOAA Administrator Rick Spinrad.

Since it started on July 13, the Dixie Fire has grown to become the largest single fire in the state’s history, burning over 600,000 acres and more than 1,100 structures. Meanwhile, meteorologists expect fire-driving windy conditions in regions that need it least in central California.

Mountain snow melted away nearly a month ahead of schedule, leaving reservoirs without their usual inflow of freshwater.
NASA/Terra-Modis

Last month, California’s Death Valley recorded a scorching high temperature of 130 degrees on July 11. That ties the hottest reliably recorded temperature anywhere on Earth and puts an even bolder exclamation point on an already unprecedented summer for numerous regions.

One village in British Columbia topped 121 degrees, the hottest temperature ever recorded anywhere in Canada. Within days, a wildfire tied to the heat burned down the majority of the same town.

These record-toppling, early-season heat waves, related droughts and wildfires in the West are exacerbated by the climate crisis and have become nearly annual events. Portland, Oregon, hit an all-time high of 112 degrees Fahrenheit on June 27 and then broke that record the following day by notching a high of 116. All this has some beginning to seriously consider the prospect that ratcheting temperatures and severe lack of rainfall could be permanent.

Here’s everything you need to know about the ongoing drought in the West as it reaches epic proportions.

How can I monitor drought conditions?

The darker the red on the map, the worse the drought. These are the conditions as of Aug. 10.
University of Nebraska-Lincoln / Screenshot by CNET

One look at a heat map of the drought in the Western US states may be enough to send the message home. Numerous websites and organizations keep tabs on the worsening meteorological conditions, including this drought monitor from drought.gov, a site from the National Integrated Drought Information System.

You can compare current drought conditions with historical data, and further search to see how the sky-high temperatures and shrinking groundwater affect your neighborhood. (You’ll enter your ZIP code.) The site updates each Thursday with the most recent information.

How severe is the Western drought?

As of August 10, over 25% of the Western US was experiencing exceptional drought, which is what the US National Drought Monitor considers the most intense level of dryness, and more than 98% of the West is seeing some level of drought. Prior to this cycle of dryness, which started in November, the biggest proportion of the West dealing with exceptional drought at any one time during the last 20 years was just 12%.

In other words, the extent of the most extreme level of drought in the West is more than double what it’s been at any other point this century. And research that doesn’t even include the last two years suggests the period between 2000 and 2018 in the Southwest was the driest such span seen in over four centuries. This is where all the talk about a megadrought comes from: It’s defined as a prolonged drought lasting two decades or longer. Arguably, parts of the West are already there.

In the shorter term, this is the second consecutive dry year for the West. Water levels are at historic lows in many of California’s reservoirs, as well as at other key stores around the region including Lake Powell and Lake Mead, which are formed by the Glen Canyon and Hoover Dams on the Colorado River, respectively. These low marks are primary drivers behind this week’s historic water shortage declaration.

Monsoon moisture in Colorado has significantly lessened the drought situation in that state, but most of the rest of the west has seen no such relief.

See also: Don’t delay when preparing your home for wildfire season

On June 24, Palm Springs, California, tied the highest temperature ever seen in the city: 123 degrees F (50.6 Celsius). In the same week, Santa Fe, New Mexico, which sits 700 miles (1,127 kilometers) to the east at an elevation of 7,200 feet (2,195 meters) tied its all-time high of 102 degrees F (38.9 C). The previous records at these locations were set in the heat of summer, in July and August. This year’s heat wave started before summer even officially began.

What states are in a drought in 2021?

As of Aug. 10, there was at least some level of drought in at least one county in 42 of 50 US states. Exceptional drought was seen in 12 states: Minnesota, North Dakota, Colorado, New Mexico, Arizona, Utah, Nevada, Montana, Idaho, Oregon, Washington and California. California, Utah, southern Nevada and the region east of the Cascade range are the areas where the exceptional dryness is most widespread. This includes the heavily populated San Francisco Bay Area and the inland central forests to the north, which are a tinderbox for the second year in a row.

Additionally, there are 10 states where the entire state was suffering from some level of drought or excessive dryness: North Dakota, South Dakota, Montana, Utah, Arizona, Idaho, Nevada, California, Washington and Oregon.

What does it mean for people living in the West?

Fire restrictions are already in place across much of the region and smoke or haze from wildfires continues to be a feature of daily life in the Southwest this month.

If conditions worsen, entire national forests, parks and other public lands may be closed off to certain types of access, impacting numerous small towns across the area that depend on outdoor recreation and tourism. That’s to say nothing of the rivers and lakes that also support local economies but are rapidly drying up.

Back in June, California started to cut off water supplies to farmers and other users in much of its Central Valley and the Russian River watershed, where the drought is at its worst in the state. The Central Valley is one of the most productive agricultural regions in the world.

“Conditions in the Russian River watershed have deteriorated rapidly and are already worse than those experienced during the last drought,” said Joaquin Esquivel, chair of the State Water Board.

The board is struggling to meet demand for agricultural needs while preserving required water flow for endangered fish species and drinking water supply for downstream cities.

The declaration of a water shortage in the Colorado River Basin means less water allocated to Nevada, Arizona and Mexico in the coming year, with Arizona likely hit the hardest.

So far there doesn’t seem to be any indication that urban taps will be shut off this year, but officials are urging people to conserve water to help avoid a worst-case scenario.

Is climate change to blame?

The climate crisis, largely driven by human activity, is making the problem worse.

A study of the most recent intense period of drought in California found that human-caused global warming “is increasing the probability” of the warmer and drier “conditions like those that have created the acute human and ecosystem impacts associated with the ‘exceptional’ 2012-2014 drought in California.”

Other studies also reach similar conclusions, which is what we hear a lot about climate change: It isn’t to blame for these extreme weather events, but it does make them more likely and more intense.

“Currently, climate change has caused rare heat waves to be 3 to 5 degrees warmer over most of the United States,” climate scientist Michael Wehner of Lawrence Berkeley National Laboratory, said in a recent statement.

A smoke-filled sky over the Bay Area in 2020 gave the sun an eerie Martian glow.
James Martin/CNET

When will the drought end?

It would take quite a deluge of precipitation to turn this summer into an average year in the record books. Strong monsoon moisture could reduce currently biblical drought conditions to just extreme or really bad conditions. This has been seen in much of Colorado and some parts of New Mexico and Arizona where July was actually pretty wet, but 2021 is still shaping up to be a pretty dry year along the West Coast and will perhaps set a new standard for how we define what a dry year is.

Over the longer term, it appears that the predictions we’ve heard for the past couple of decades of a great Southwestern megadrought are becoming reality. Many expect the trend to hold deep into the middle of this century. If that’s the case, even bigger changes like expanded desertification start to enter the picture.

However, that could be generations away, and things may shift — we can all hope. In the meantime, though, it’s best to start being smarter about how you use water and energy if you live in the West, and if you live elsewhere, those of us here would sure appreciate a reexamination of everyone’s carbon footprint.

Stay safe out there.

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