A Brief Overview of the River and the Megadrought

Several months have passed since my last update on the megadrought. While immediate changes have occurred in the river's conditions, the long-term outlook remains largely unchanged. For those who missed it, here is a brief overview.

The Colorado River watershed spans approximately 246,000 square miles, nearing the size of Texas. This river is essential for residents of the Intermountain West, flowing through seven states and two Mexican states. It serves as the primary water source for around 40 million people and generates electricity for regions as distant as Nebraska, thanks to its major reservoirs at Lakes Powell and Mead.

In hydrological terms, the river basin is divided into two sections: the Upper Basin, which includes Wyoming, Colorado, New Mexico, and Utah, and the Lower Basin, comprising Arizona, Nevada, and California. Although Native American tribes have lived along the river for centuries, European exploration only began in earnest with John Wesley Powell's expeditions from 1869 to 1871, leading to the naming of Lake Powell.

Brigham Young and early Mormon settlers were among the first non-Native Americans to establish communities near the river, creating their own state of Deseret. They utilized local streams and rivers to irrigate the arid Utah landscape.

In an effort to manage the river's resources equitably, the Colorado Compact was created in 1928, allocating each state a certain percentage of the river's flow, often based on historical data from a wetter period. Consequently, the allocations made to each state have increasingly fallen short of their needs. The construction of Hoover Dam and Glen Canyon Dam aimed to conserve water, generate electricity, and create recreational spaces.

Drought has plagued the region since 2000, significantly impacting the Lower Basin states. Population growth has begun to exceed the river's supply. In 2007, a tiered water management system was introduced to regulate the outflow from Lakes Powell and Mead based on lake levels. As of 2022, the system reached Tier 2a, with Tier 3 indicating "dead pool" status, where water flow ceases entirely. Fortunately, after a wet winter, the river has reverted to a Tier 1 shortage.

Water is quantified in acre-feet, where one acre-foot equals the volume needed to cover an acre of land one foot deep, equating to about 326,000 gallons.

To understand the overall flow of the Colorado River, one must consider its tributaries, including the Green River from Wyoming, the Gunnison and Dolores Rivers in Colorado, the Gila and San Juan Rivers in New Mexico, the Virgin River in Utah, and the Little Colorado and Gila Rivers in Arizona.

Wyoming

> “In Cheyenne, Wyoming, the frost-free season lasts barely four months. Such conditions limit crop choices to low-value options like alfalfa, wheat, and barley, which require extensive land for minimal profit.” > ~Marc Reisner, Cadillac Desert

As the second highest state in the contiguous U.S., Wyoming experiences rapid warming at its highest elevations. Rising temperatures influence snowmelt patterns, runoff rates, and evaporation, resulting in reduced water availability for the Green River, the Colorado's most significant tributary.

The western portion of Wyoming is not particularly conducive to agriculture, with alfalfa being the primary crop, primarily for livestock feed.

While the Green River originates in the Wind River Mountains of Wyoming, where water appears plentiful, it eventually converges with the Colorado in Canyonlands National Park, Utah.

Certain areas of Wyoming are classified as abnormally dry, according to the U.S. Drought Monitor, including the Green River headwaters, which have been increasingly affected over the past three months. Despite experiencing its wettest summer in 2023, the state remains vulnerable to drought conditions, ranking as the fifth driest in the country.

Flaming Gorge Reservoir, the largest on the Green River, begins in Wyoming and extends into Utah. In 2021, when Lake Powell's level approached critical status, Flaming Gorge released 125,000 acre-feet of water to help raise it. The situation worsened in 2022, with 500,000 acre-feet released to boost Lake Powell's levels. Thanks to last year's favorable conditions, Flaming Gorge's water levels have rebounded and now stand at 84% capacity.

Maintaining a high elevation at Flaming Gorge is crucial for managing emergencies downstream, which directly relies on weather conditions.

Colorado

> “The Colorado River rises in the Rockies as a cold trickle from snowmelt cascading down Long’s Peak, embarking on its 1,500-mile journey to the Gulf of California.” > ~Marc Reisner, Cadillac Desert

In 2023, I focused extensively on the Colorado River's headwaters. The snowpack in Colorado's Rockies significantly influences the river's flow. Currently, the snowpack is above average, aided by the effects of El Niño and atmospheric rivers from the West Coast.

Beyond its tributaries, Colorado is both the starting and ending point for substantial snowmelt flow into the river. The San Juan River contributes runoff from southern Colorado's mountains and the Virgin River in Utah, but the Colorado predominantly traverses desert terrain. Notably, California's rivers do not feed into the Colorado, as they flow directly into the Pacific Ocean.

Various mountain ranges in Colorado are experiencing drought conditions ranging from abnormally dry to moderate, severe, or extreme. The latter classification pertains to the Rio Grande headwaters, which flows east of the Continental Divide towards the Gulf of Mexico. The impact on the Colorado will become evident in the New Mexico section below.

As a child, I spent time along the Los Piños River in southwestern Colorado, a tributary of the San Juan River that flows into the Colorado at Lake Powell. To me, it is a stunning river, with cascades flowing through forested ravines in the La Plata Mountains, nourishing the lands below. I feel a connection to the Colorado River, remembering my father fishing in its currents while I watched, yearning to join him but swept away by the rushing waters.

Three significant dams on the Gunnison River—Crystal, Blue Mesa, and Morrow Point—play a role in maintaining flow for downstream reservoirs, having done so in 2021 and 2022. However, their levels dropped, and only considerable runoff from the 2022–2023 season brought them back to nearly full capacity.

The Bureau of Reclamation will continue to rely on these reservoirs during drought periods downstream, but Colorado officials argue that this practice drains resources unfairly. They contend that the Lower Basin states (Arizona, Nevada, and California) overdrew over one million acre-feet of water between 2019 and 2021 and should not be expected to shoulder future burdens.

Meanwhile, the demand from Colorado's Front Range is increasing. Approximately 75% of Colorado's residents live in the Denver and Colorado Springs metropolitan areas, and at least 50% of their water supply is sourced from the Colorado River. With significant growth in many cities, water consumption from the river's headwaters is set to rise further.

Utah

> “The landscape beyond the river is dominated by rock formations—cliffs, plateaus, terraces, and crags—creating thousands of uniquely shaped forms, with the river weaving gently among them.” > — John Wesley Powell

As the second driest state in the U.S., Utah's contributions to the Colorado River are limited. These include the Green River, which starts in Wyoming, the San Juan River from Colorado, and the Virgin River, which has its headwaters just north of Zion National Park.

Compared to other tributaries, the Virgin River remains relatively wild but flows through sparsely populated regions until it reaches St. George. This area has a significant demand for water, and plans are underway to construct a pipeline from Lake Powell to the city's water reservoir.

The projected cost of the Lake Powell Pipeline could reach up to $2.8 billion, with strong backing from developers eager to support St. George's growth, which is projected to reach 425,000 residents by 2060. This would increase the number of households from the current 62,416 to an estimated 203,901.

Lake Powell is critically low, currently at 36% of its capacity, approximately 135 feet below full pool. The Bureau of Reclamation predicts a shortfall of two million acre-feet of water this year. Upstream lakes may need to release more water than initially planned to sustain Lake Powell's levels. A withdrawal of water for the Lake Powell Pipeline could jeopardize the lake’s future.

Having visited Lake Powell during a 2022 road trip, I was struck by the visible "bathwater" stains marking the shoreline. Until you witness them firsthand, the enormity of the water loss is hard to comprehend.

Some advocate for dismantling Glen Canyon Dam to restore the Colorado River's natural flow, a proposition primarily supported by environmental groups. However, such a move would eliminate any chance of constructing the pipeline.

This anticipated growth hinges on the assumption that the pipeline will be built, as highlighted in the University of Utah’s Long-Term Planning Projection Summary. Approximately 30% of St. George's economy relies on construction. Mayor Michele Randall has remarked, "If growth halts, our economy would collapse overnight."

Deep wells are being drilled far beyond city limits, threatening the water supplies of smaller communities.

To explore more about St. George and its questionable viability as a city, click here.

> “The Colorado has no more water to give.” > ~Zach Frankel, executive director of the Utah Rivers Council

New Mexico

> “I never appreciated how much water enhances a river until I arrived in New Mexico.” > ~Mark Twain

You might be curious as to why New Mexico is involved in the Colorado River discussion, given that the river doesn't flow through it.

The reason lies in its major tributary, the San Juan River, which feeds into the Colorado. Further south, the Gila River, often dry before reaching the Colorado, only flows during monsoon season.

The San Juan originates in the San Juan Mountains of southwestern Colorado and flows south to New Mexico, where it is dammed at Navajo Lake.

As a child, I spent time at Navajo Lake, where my father would fish. Though I was too scared to handle fish, I enjoyed exploring the surrounding wildlife.

The San Juan flows through the northwestern part of New Mexico, passing near the Four Corners area and into southern Utah before reaching Lake Powell. Known as one of the muddiest rivers in the U.S., the San Juan deposits significant sediment into Lake Powell, forming its own delta.

In exchange, New Mexico receives 11.5% of the Upper Basin's water allocation.

Currently, 96% of New Mexico is experiencing some level of drought, with southeastern regions like Roswell and Carlsbad suffering the most, alongside areas in the northwest, including Farmington. Much of New Mexico relies on the North American monsoon for river and reservoir replenishment. The 2023 season has been dubbed a "nonsoon," as it failed to deliver.

Water from the Colorado River is diverted to the Rio Grande through the San Juan-Chama project, supplying cities like Albuquerque and Santa Fe with drinking water. Approximately 70% of Albuquerque's water is sourced from the Colorado via the Rio Grande. Without this pipeline, the Rio Grande would dry up even more frequently, as evidenced by it running dry north of Albuquerque in 2022.

Having lived in Albuquerque for five years, I can attest to the valley's rain shadow effect. The lack of last year's monsoon led to only 6.5 inches of rainfall since early 2023, a stark contrast to Las Vegas' 12.12 inches and comparable to Phoenix's 6.31 inches.

While snowpack levels in New Mexico's mountains are above average, they are unlikely to resolve the drought soon. A forecast of prolonged above-average temperatures and minimal precipitation could lead to another challenging year, as high temperatures will quickly melt the snowpack, rather than allowing a slow, beneficial release into summer.

Conclusion

The Upper Basin serves as a reservoir for water destined for the Lower Basin. While it was not intended to be a lifeline, the Lower Basin's escalating demands continue to deplete its resources as climate change progresses.

I fear complacency may set in. With two wet winters behind it, California might neglect conservation efforts, despite being the largest user of the river. Both Lakes Powell and Mead are currently only one-third full, and under present circumstances, it is likely they will never return to full capacity.

The Upper Basin is the primary water source, while the Lower Basin is the chief consumer. As the Colorado Compact approaches expiration, the future allocation of the river's water remains uncertain. Collaboration among states and conservation efforts from users will be essential.

Next, we will examine the Lower Basin, the impact of El Niño, and the circumstances surrounding the two largest lakes.

The decisions made by federal authorities will play a pivotal role.

Sources for the series include: - “St. George, UT Will be Among the Fastest Growing Cities by 2060” by Samuel Stebbins on 24/7WallSt.com, 9/16/2022 - “Threat of massive drinking water crisis looms over American regions: ‘There will be parts of the U.S. that run out’ by Wes Stegel in TheCoolDown.com, 11/27/2023 - “Push to drain Lake Powell gaining momentum” by Greg Haas, KTLA News Los Angeles, 9/18/2023 - “Saving the Colorado River: An acre-foot at a time in the Upper Basin” by Joi O’Donoghue in the Salt Lake Deseret News, 12/21/2023 - “The Colorado River 101” by Jan Pelz on grandcanyontrust.org, 5/16/2023 - “Wyoming climate data holds ominous clues about life, economy” by Dustin Bleizeffer on energynews.com, 11/3/2021 - “It was the wettest summer on record for Wyoming — what does this mean?” by Caitlin Tan, Wyoming Public Radio, 10/5/2023 - “In America’s fastest growing metro, a rising fear water will run out” by Karen Bruillard in The Washington Post, 8/22/2022 - “Colorado’s Blue Mesa Reservoir still part of plan to keep water levels at Lake Powell from falling too low” by Shannon Mullane in the (Denver) Colorado Sun, 10/24/2023 - “Dozens of Colorado farmers, ranchers and one city offer to cut Colorado River water use in exchange for $8.7M,” by Shannon Mullane in the (Denver) Colorado Sun, 2/13/2024 - “Here’s what feds think will happen with Lake Powell’s water level this year” by Anastasia Hufham in the Salt Lake Tribune, 12/30/2023 - “A Dwindling Mighty River” by Nadav Soroker in Searchlight New Mexico, 9/21/2023 - “Water Security on the Navajo Nation” presentation created for the Department of the Interior, OEPC.

Earlier stories on the Megadrought by Arthur Keith:

• The American West: Long on People, Short on Water
  • Part 4A: As the Colorado River Goes, So Goes The West
• How The West Went Dry
  • The history behind the West’s megadrought, simplified
• Water Crisis In The West, v5.0 — The Colorado River Story
  • It’s Happening Faster Than I Can Write About It