Click the link to read the article land desk website (Jonathan P. Thompson):
in the previous comment Land Desk Dispatch of the Week on the Colorado River Agreement of the Lower Basin States, reader Anne Bond had some interesting questions/issues that I wanted to address. First, let me summarize Anne’s question.
- What impact will thousands of acres fallow? Will it lead to another dust bowl?
- Will electricity from the dam be used to carry water (for example, to power pumps for the Central Arizona project)?
- And what purpose do the two reservoirs (Powell and Mead) serve within the system, and how will that factor into interstate negotiations?
Today we will only discuss the first two. That’s all there is room for.
My short answer to question 1 is “I don’t know”. One of the problems with this agreement is that few details have been made public, making it difficult to understand what the implications will be.
However, we do know that downstream states plan to secure 3 million acre-feet of water over three years, or about 1 million acre-feet per year, by paying water users to reduce their consumption. ing. Federal funds will be used to reimburse people for 2.3 million acre-feet of these cuts, and state, local, or other funds will be used for the remaining 700,000 acre-feet. Agriculture is by far the largest user of the Colorado River’s water, so it’s reasonable to speculate that most of these savings come from paying farmers not to irrigate their crops. and it makes more sense than paying people not to water their lawns. This is a good place to start.
i also read report Imperial Irrigation District, the basin’s largest single water user, said it plans to abandon 250,000 acre-feet per year (included in the above amount).
One of the most abundant crops in the Colorado River Basin is primarily hay. alfalfa. It is also one of the most coveted crops. Growing 1 acre of alfalfa will drink about 4 acre feet of water per year, depending on location, climate, and length of growing season. Alfalfa is grown in Colorado’s high, cool San Luis Valley. Consumes about 2 acre feet per year; Crops can be harvested in California’s sea level Imperial Valley, one of the hottest places in the nation. 6+ acre feet of water required per year.
Fallow is likely to occur in hot, dry southern Arizona and California, so we use the figure of 6 acre-feet per year. This means that a total of 167,000 acres of alfalfa fields, roughly three-quarters of the Salton Sea, would need to be irrigated to stop in order to reach the water reduction target. Targeting low-thirst crops will require larger areas of fallow. Assuming the fields they fellowed were alfalfa, about 42,000 acres of them would be in the Imperial Irrigated District. More background: An MIT study found that he would need 90,000 acres of solar panels to replace power generation at the Diablo Canyon nuclear power plant.
Yes, it’s a huge area, and if you stop irrigating it, it’s very likely to turn into a dry, weedy area. It probably won’t look like a dust bowl right now, but it can get ugly, especially in dry summers. For example, in California’s San Joaquin Valley, a groundwater management program (unrelated to the Colorado River crisis) forces farmers to fallow. Leads to serious dust and air quality problems.
The Imperial Valley is next to the Salton Sea and has rich air. and the lungs of the inhabitants — It’s already covered in dust. Fallowing all the alfalfa fields in the Valley would certainly make the problem worse. At this time, it is not clear where the fields will fallow, except that it will be partly in California and partly in Arizona (Nevada drains nearly all the water of the Colorado River to Las Vegas and It is used as municipal water in the surrounding area).
Media outlets reported that states plan to pay these farmers $1.2 billion out of the federal Inflation Control Act. That translates to a $521 price tag per acre-foot of water that doesn’t run into the fields. Using the figure of 6 acre-feet per acre of alfalfa means that Imperial Valley farmers can earn over $3,000 per acre without growing anything.
It’s not a bad deal.According to the University of California, Davis Farmland data layer siteFarmers in the Imperial Valley harvested 144,000 acres of alfalfa hay in 2020. They produce 1.14 million tons of alfalfa hay worth $200.44 million, or an average of $1,391 per acre. In other words, a farmer can earn twice as much without farming as he does from farming his land.
But it will also reduce the supply of alfalfa, causing higher prices, likely spilling over to the beef and dairy industries, where most of that alfalfa is shipped. It could end up in the ice cream and cheese section of your local grocery store.
2. The second point Anne made was that it takes a lot of energy to move water from the Colorado River to the fields and cities.It also includes electricity generated by dams on the Colorado River. This means that when irrigators use less water on the Colorado River, more water remains in the river and can generate more energy as it passes through the dam’s turbines, allowing more water to reach the fields. I can move it… Wow, I’m getting dizzy here.
This is a classic example of the water-energy connection, in this case the water-energy-water connection, and one of my favorite topics.
Glen Canyon, Hoover, and several other dams on the Colorado River system are hydroelectric. This means that electricity can be generated through turbines as water flows through the dam. When the level of the reservoir decreases, power generation capacity of the dam. And when the level of the reservoir drops below the opening to the penstock, the tube leading to the turbine, power generation stops completely.
There is good reason to surprise people in this era of climate change. The warmer it gets, the more electricity it takes to run air conditioners and the more water irrigators need to put on their crops. That means more electricity is needed to move the water. But the warmer it gets, the lower the reservoirs and the less power we have. ah!
The Central Arizona Project is one of the largest water-moving projects on the Colorado River. Its pumps draw water from the Colorado River on Lake Havasu and travel 536 miles across the Arizona desert (traveling in uncovered canals, which evaporates a lot of water), with a total elevation gain of 2,900 feet. exceed. It requires a lot of energy. In fact, it requires so much power that the coal-fired Navajo power plant was built in large part to run his CAP pumps.
2 million megawatt hours: Annual power consumption of pumps at the Central Arizona Project.
2 million megawatt hours: Annual power consumption of 5 pumping stations Colorado River Aqueductwhich delivers water to Los Angeles and surrounding areas.
2.5 million megawatt hours: Annual power generation at Glen Canyon Dam in 2022
3.9 million megawatt hours: Annual Power Generation of Glen Canyon Dam in 2008
1.5 million megawatt hours: Hoover Dam Annual Power Generation in 2022
259 million megawatt hours: Annual power consumption in California.
The Navajo Power Plant was decommissioned in December 2019, requiring CAP to source power elsewhere. Currently, the project derives 70%-80% of its power from market forwards and short-term purchases. 12% to 15% from Salt River Project Power Company. 6% from Hoover Dam. 4% from photovoltaic installations. About half of the power for the Colorado River Aqueduct pumps comes from the Hoover and Parker Dams, with the remainder coming from a combination of market purchases and hydroelectric power generation within the aqueduct system.
Then there is the question of how much of the dam’s electricity is used to move water. The Western Regional Power Authority sells electricity from Glen Canyon Dam and 56 other hydroelectric dams. Here’s a breakdown of who buys that power:
Only 4% goes to irrigation districts, but it can be assumed that some of the many other categories go to water movement and treatment. Therefore, all these customers, including water utilities, will have to find new sources of power if the dam’s hydropower capacity shrinks or disappears altogether.
