Many eyes are on Lake Powell and the power pool #ColoradoRiver

A high desert thunderstorm lights up the sky behind Glen Canyon Dam -- Photo USBR
A high desert thunderstorm lights up the sky behind Glen Canyon Dam — Photo USBR

Here’s a look at the Lake Powell power pool and the cascading effects if the reservoir drops below the level necessary to continue to deliver power to the southwestern US, from Allen Best writing in The Denver Post:

Colorado water leaders used a curious approach last week in announcing a new water conservation program involving the Colorado River. They talked about electricity and the effect of spiking prices on corn farmers in eastern Colorado, ski area operators on the Western Slope, and cities along the Front Range.

The scenario? A Lake Powell receding to what is called a minimum power pool, leaving too little water to generate electricity. Glen Canyon Dam, which creates the reservoir, is responsible for 81 percent of the power produced by a series of giant dams on the Colorado River and its tributaries, including those on the Gunnison River. This electricity is distributed by the Western Area Power Administration to 5.8 million people in Colorado, Arizona and other states.

Should this power supply be interrupted, WAPA would make good on its contracts with local utilities by buying power in the spot market, such as from gas-fired power plants. But extended drought on the Colorado would certainly increase prices to reflect the higher costs of replacement by other sources.

Hydropower is far cheaper than renewables but also fossil fuels. Rural electrical cooperatives get nearly half the production, followed closely by municipalities, including Colorado Springs, Delta and Sterling, plus Longmont, Loveland, Estes Park and Fort Collins.

Right now, WAPA is selling the energy from Glen Canyon and the other dams at $12.19 per megawatt-hour with a separate charge for transmission. Just how much prices would increase in event of prolonged interruption is speculative. The same agency, however is shoring up August deliveries with purchases of power from other sources at $55 per megawatt-hour, according to Jeffrey W. Ackerman, the Montrose-based manager of WAPA’s Colorado River Supply Project’s Energy Management Office.

This illustrates the bone-on-bone relationship between energy production and water during time of drought.

Yet the broader story about the Colorado River is about a narrowing razor’s edge between supply and demand. There’s no crisis, but water officials are planning for one. A healthy snowpack in Colorado last winter helped, but did not solve problems. The basin as a whole was still below average, as it has been 11 of the last 14 years.

“As leaders, we simply cannot wait for a crisis to happen before we come together to figure out how to address it,” said Jim Lochhead, chief executive of Denver Water. “That would be irresponsible.”

Denver Water and providers in Arizona, Nevada and California, plus the U.S. Bureau of Reclamation, are pooling $11 million to launch a demand-management program. Utilities such as Xcel Energy have similar programs, offering to pay customers willing to suspend use of air conditioners for a couple hours on hot summer afternoons.

In this case, $2.5 million is being allocated to fund programs that would yield reduced demands in Colorado and other states upstream of Lake Powell. The obvious idea is fallowing of crops, such as a hay meadow, with the irrigator to be reimbursed. But Lochhead stresses that it’s a blank chalkboard. The intent is to solicit ideas and then “demonstrate effective demand-management techniques.”

“It’s not something we expect to do. It’s not something we want to do, but if the drought continues, we want to be ready,” says John McClow, Colorado’s representative on the Upper Colorado River Commission.

The bulk of the $11 million will be allocated to demand-management programs in the lower-basin states.

Doug Kenney, director of the Western Water Policy Program at the University of Colorado’s Getches-Wilkinson Center for Natural Resources, Energy and the Environment, sees the agreement as representative of broad shift in states sharing water from the Colorado River. “In the past, they could get together to build things such as dams. Now, they are teaming up to save water,” he says. “That’s a paradigm shift.”

An effort involving The Nature Conservancy and water agencies based in Durango and Glenwood Springs has been underway for five years. That parallel effort, however, is driven by a different trigger: the prospect of a compact curtailment or “call.” The 1922 Colorado River Compact requires Colorado and the other upper-basin states — Wyoming, Utah and New Mexico — to deliver an average 75 million acre-feet over any given 10-year period.

Upper basin states at this point have a cushion of 15 million acre-feet, or two years’ supply. Yet abundant snowfall last year in Colorado only slightly filled Lake Powell. One relatively good year does not compensate for several bad ones.

Always hovering in the background is the prospect of even worse. Tree rings from across the River Basin provide clear evidence of longer, more intense droughts 800 to 900 years ago. An additional layer is the prospect of higher temperatures caused by global warming.

Chris Treese, external affairs director for the Glenwood Springs-based Colorado River Water Conservation District, acknowledges a growing sense of urgency. “We could be back in a near-crisis or crisis situation in as little two or three years,” he says. And for water planners, who typically try to think decades ahead, that’s a current event, he adds. [ed. emphasis mine]

How likely is this dead pool? U.S. Bureau of Reclamation modelers in April found a 4 percent chance of a minimum power pool in 2018 and a 6 percent in 2019. The models are based on recorded hydrology of the last 105 years.

What if Powell does decline and electricity cannot be generated? It depends upon how long the shortage lasts. A longer outage would affect electrical consumers from Arizona to Nebraska. “We’re struggling to quantify the impact,” says Andrew Colismo, government affairs manager for Colorado Springs Utility.

Tri-State is the single largest consumer, purchasing 28 percent of all power produced in 2012 from the dams. It sells this power to 44 member co-operatives in a four-state region, including those who sell to irrigators in eastern Colorado.

Irrigation is a huge consumer of cheap power. In northeastern Colorado, Holyoke-based Highline Electric meets demand that ranges from a low of 25 megawatts to a high of 190 megawatts, the latter occurring when irrigation pumps are drawing water from the Ogallala aquifer to spread across 123-acre circles of corn, beans and other crops. Some large irrigators pay hundreds of thousands of dollars annually in electrical costs, says general manager Mark Farnsworth.

The irony is that if a drought occurs accompanied by heat, as is usually the case, irrigators will probably pump more water and air conditioners will work even harder. Power demands will rise as water levels drop.

Tri-State spokesman Lee Boughey says existing rate structures anticipate both droughts and heavy precipitation.

Lochhead and others also point to other ripples from interrupted power sales. Revenues from hydroelectric sales, which were $198 million last year, are used for a great many programs: selenium control in the Delta-Montrose area, work to maintain ecosystem integrity downstream from Glen Canyon and ongoing efforts to preserve four endangered fish species in the Colorado River and its tributaries.

On Wednesday, Lochhead met with an interim legislative water committee at the Colorado Capitol to report about the new agreement. The testimony all day had been about potential measures to expand water conservation as Colorado tries to figure out how to accommodate a population expected to double from today’s 5.3 million residents to 10 million people by mid-century without drying up rivers and farms.

Denver Water already serves 1.3 million, but gets about half of its water from the Western Slope. “We have a vested interest” in the Colorado River, Lochhead told legislators.

One outstanding question is whether Denver and other water providers on the High Plains should try to be able to get additional water from new or expanded transmountain diversions.

With this story from Lake Powell, the take-home message is don’t count on it.

Allen Best writes frequently for The Post about water and energy and also publishes an online news magazine, found at http://mountaintownnews.net.

More Colorado River Basin coverage here and here.

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