Agriculture primarily uses water from the river that supplies forty million people with drinking water. A federal organization in the United States is looking for suggestions to help preserve water and increase the capacity of two dams to generate energy.
The overexploitation of the waters of the Colorado River is having such a negative impact on the river that there is a significant possibility that, over the next five years, it will no longer have sufficient flow to generate adequate energy. Because of this, the organization that is responsible for the management and protection of the water and dams in the western United States has set a deadline of August 15 for the seven states in the United States that the Colorado River traverses along its 2,330-kilometer course to submit plans that will save between 2.5 and 4.9 billion cubic meters of water per year. The Colorado River flows through seven of these states.
The Glen Canyon and Hoover dams on the Colorado River were responsible for forming Lake Powell and Lake Mead, now the two most significant reservoirs in the United States. However, the rocks surrounding the lakes bear the evidence of a gradual emptying of these enormous water surfaces: whitish lines identify the level the water has previously reached, far higher than the level it is at right now. In addition, by the end of 2022, the water that may be held in lakes Powell and Mead will be cut to 25 percent of its capacity.
In light of this situation, and to prevent the reservoirs from getting so low that it becomes impossible to move water and produce electricity, the commissioner of the Bureau of Reclamation, which is the agency that manages and protects water and dams in the United States, has given the states an ultimatum to find ways to make radical cuts in their use of river water: “A reduction of between 2.5 billion and 4.9 billion cubic meters of water is needed to ensure critical levels in 2023.”
According to an article published by KUNC, the public radio station in Colorado, the yearly water usage of the Colorado state river alone is roughly equivalent to the minimum 2500 million cubic feet that must be decreased. However, this presents a significant difficulty. Tanya Trujillo, the Under Secretary for Science and Water at the United States Department of the Interior, made these remarks in an interview with a local radio station. “We’re going to need to do things we’ve never done before,” she stated.
Agricultural pressure (and more)
The repercussions of the drought that has persisted since the turn of the millennium are a source of concern for scientists, who have been making dire forecasts regarding the Colorado River for several years now (that is why it is also known as the “Millennium Drought”).
According to research published in 2020 by the United States Geological Survey, the river flow has already fallen by around 20 percent on average compared to what it was throughout the 20th century. The study relates this loss to global warming. The Rocky Mountains, the source of the river, are seeing a decrease in the amount of snowfall due to climate change, which also exacerbates the drought plaguing western North America for the past two decades and has caused periodic heat waves and mega-fires.
However, this is only the beginning of the problem of overexploitation. The Colorado River, upon which the livelihood of forty million people depends, has seen unprecedented growth in urbanization along its banks. According to the New York Times, in the past ten years, Phoenix has experienced more growth than any other city in the United States. The New York Times also reports that several other urban areas in Arizona, Nevada, Utah, and California (bordered by this river) are among the fastest growing.
But cities are not even the most significant Colorado River water users. The most important contributor is agriculture, which uses the river’s water in several inefficient ways because it occupies 2.3 million acres of land in the area.
It is estimated that 75% and 80% of the water taken from the Colorado River is utilized for agricultural purposes, specifically the cultivation of lettuce, alfalfa, and orchards. Cities have expanded thanks to the successful management of their water resources. “Even if all municipal water usage were to cease, you would still not reach the target cut-off point, somewhere between 2,500,000 and 4,900,000,000 cubic meters of water. Participation is going to be required from every industry, “In an interview with KUNC, Colby Pellegrino, the deputy director of the Southern Nevada Water Agency, which is in charge of the public water supply serving the Las Vegas metropolitan region, said the following:
Along with the US-Mexico Water Treaty of 1944, the Colorado River Compact was signed in 1922 and is the document that establishes the rules for the distribution of the river’s water among the seven states in the United States (Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming) that the river flows through (as the river still bathes two states of that country, and flows there).
The Compact creates two basins for the river: the upper basin, New Mexico, Colorado, Utah, and Wyoming, and the lower basin, which includes just Wyoming (Nevada, California, and Arizona). It outlines the amount of water to which they are entitled (9,200 million cubic meters per year for each basin), as well as the rules that must be followed to ensure that users in the upper basin do not spend more money than they are allowed to, as well as the mechanisms that must be in place to ensure that compensation is made if there are any violations.
The only people who were overly optimistic about the river’s future flow were the Pact negotiators. They assumed that the flow at Lees Ferry, where a flow meter was installed and considered the dividing point between the two basins, would be 21,500 million cubic meters per year.
According to a study published in Science, “But the natural flow in Lees Ferry during the 20th century averaged 18,700 million cubic meters per year.” This study, which was written by Kevin Wheeler of the Institute of Climate Change at Oxford University (UK) and presented various scenarios of reductions in water use and their impact on reservoir level stabilization, states that “But the natural flow in Lees Ferry during the 20th century averaged 18,700 million cubic meters per year.”
Because of this, the situation envisioned in the Pact does not match the reality now, and the disparity between the two will become even more pronounced due to the many pressures placed on the river. The upper basin of the Colorado River and the lower basin of the river are both entitled to the same quantity of water from the Colorado River; yet, the higher basin does not utilize the water to the same extent as the lower basin. This causes tensions between the two basins.
Most of the water in Nevada, California, and Arizona (the states that make up the lower basin) is used for urban and agricultural irrigation. In contrast, the states of Colorado, Utah, Wyoming, and New Mexico have managed to keep their water use far below the permitted levels.
Because of these discrepancies, officials responsible for water management in the upper basin have advised that the lowest basin should focus on a tremendous effort toward reduction. In addition, they have plans for significant building projects that, should they be carried out as intended, will increase their reliance on the water supplied by the Colorado River rather than decrease the water they use. Chuck Cullom, executive director of the Upper Colorado River Commission, stated to KUNC that “Since it’s the lower basin that has the most significant volume of uses, it makes sense that that’s where most of the solution is coming from,”
Perform the impossible, and do it quickly.
According to the article published in Science, it requires effort from both basins and must be very large. This effort must be more significant than anything considered up to this point. The researchers modeled one hundred distinct potential outcomes and management approaches for the river, and their findings led them to the conclusion that prompt action is required to combat the situation.
Suppose uses continue more or less as they are now. In that case, there will be a sharp decline in the Powell and Mead reservoirs, to the point where it will endanger electricity production. If the “Millennium Drought” continues, the reservoirs could reach 12 percent of their capacity before stabilizing. In a status quo scenario, which is a scenario in which uses continue more or less as they are now, there will be a sharp decline in the Powell and Mead reservoirs. According to what the group writes in Science, “At this volume [of water], both Glen Canyon Dam and Hoover Dam would stop generating electricity.”
But suppose the states in the upper basin limit water use to 65 percent of the 9200 million cubic meters per year to which it is entitled. In that case, the states in the lower basin and Mexico must commit to doubling the current maximum reduction levels they have agreed to discuss. This is because the upper basin states have a greater entitlement to water. In this hypothetical situation, the lower basin would get a quantity of water comparable to that of the upper basin, which is to say that it would receive 66.7 percent of the water to which it is entitled.
If the upper basin is only allowed to use 53.3 percent of the water to which it is entitled (which is still 370 million cubic meters more than its recent use), then the lower basin would only need to reduce its use of water by 2400 million cubic meters to guarantee 77.8 percent of the water to which it is entitled. This will be the case if the upper basin is only allowed to use 53.3 percent of the water to which it is entitled.
“Our findings indicate that existing regulations are insufficient to sustain the Colorado River; nevertheless, should the so-called “Millennium Drought” continue, several consumption methods are capable of stabilizing the system. “However, we must move quickly to put these measures into effect,” the authors wrote. However, these measures would necessitate significant reductions in the water consumption that the lower basin states already carry out and would halt the investments scheduled to take place in the upper basin states over the next few decades.
According to the New York Times, it is unclear who would pay that compensation, which could run into the many billions of dollars. There are few details about the negotiations to make the necessary cuts, but some agricultural users of Colorado’s water have suggested leaving land uncultivated in exchange for compensation.
In addition, for this to be successful, scientists have to assume that the Colorado River Compact mechanism, which was created to ensure that the “water debts” between the two basins be paid off, will not be activated in this state of emergency.
The document signed 100 years ago and with overly optimistic perspectives on the river’s flow provides an equal water division between the two basins. It is mandatory for the states in the upper basin to let 9.2 billion cubic meters of water flow per year into the lower basin. Another 1.2 billion to reach the two Mexican states that border Colorado. The document was signed with overly optimistic perspectives on the river’s flow. However, the reality is that the river’s current course is no longer fulfilling the pact’s predictions regarding the river’s flow.
“While these concessions for both basins may seem unthinkable at the moment, they will be necessary if current conditions persist,” the team led by Kevin Wheeler writes in Science. “While it may not be easy to reach an agreement, it is essential.”