What It Would Take to Save Lake Powell and Lake Mead

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JFRCalifornia

Escalante-Class Member
In a recent thread, I posted my take on what it would take to raise Lake Powell to a level the would allow the return of all the key recreational infrastructure--all marinas, launch ramps, Castle Rock Cut, etc. Practically speaking, that means elevation 3588+/-. One key takeaway was that the Upper Basin states would need to greatly cutback on existing water use, especially if this level of drought continued for long. There was some good constructive feedback to that, especially related to this question: what about the Lower Basin states? Don't they need to cutback too? And this: what happens to Lake Mead?

And so I expanded and revised that study to address those issues. Now it's more a comprehensive take on the entire Colorado River watershed, what might happen, and what to do in case it does. It makes no effort to assign probabilities to possible outcomes, good or bad. I will leave that to the meteorologists and statisticians. Instead, I just present this as a possible roadmap to policy makers and water managers who need to respond to the current realities and possible futures. Here's a link to the updated study, for anyone who wants to slog through 22 pages.


Without getting into any of the details in this post, here are the main findings of that study, some obvious, some not:

1. The most important factor in maintaining Lake Powell’s volume is total water availability, primarily through snowpack in the Upper Basin. Lake Mead’s volume depends primarily on the volume of water released through Glen Canyon Dam.

2. If the next 5-year period (WY 2023-27) matches the total water availability that occurred from 2016-20 (a very modest goal in historic terms), it is possible to achieve the target Lake Powell elevation of 3588 during WY 2026, although it would require a 5% reduction in water use to achieve that goal in WY 2025. But without a 10% reduction in water use, Lake Mead would still remain well below 1075 even by 2027.

3. Continued extreme drought conditions over the next 5 years would be disastrous for both reservoirs, and to those who rely on them. Without any proportional reduction from the 2016-20 average water use in each state and Mexico, a continued period of 40% below average water availability (similar to the period 2000-04) would end power generation at Glen Canyon Dam in 2023 and at Hoover Dam in 2026. Both reservoirs would reach dead pool—Lake Powell in 2025, and Lake Mead in 2027. With drastic cuts (25%) in water use, dead pool could be avoided, and Hoover Dam would still be able to generate power, but it would not be enough to reverse the decline of each reservoir until drought conditions subsided. For the reservoirs to stabilize during this period, water use cuts would have to be in the 40-50% range.

4. Since the two reservoirs now have little margin for safety (excess volume in storage), and because the future can’t be known with certainty, it is imperative to reduce water use to the extent possible as soon as possible across the board in both the Upper and Lower Basins, as well as in Mexico. The reason why the system was able to weather the extremely dry period of 2000-04 was because when that period began, the reservoirs were collectively 87% full. By the spring of 2005, they had collectively lost nearly half their volume, and Lake Powell had dropped nearly 150 feet. Today, that cushion is gone, and the system could not withstand a similar period going forward without substantial consequences related to power, water use and recreational access.

5. To be effective, water use reductions need to be in place prior to experiencing extreme drought conditions, not in response to a crisis. If over the next few years that “worst case” scenario does not play out, those water use restrictions could potentially be eased once the reservoirs begin to recover.

6. A proportional reduction in water use would result in the largest absolute reductions for the states with the largest baseline use. Thus, with this approach California would see the most substantial cuts, while Nevada, New Mexico and Wyoming would experience the smallest cuts.

7. In general, for every 5% reduction in water use, Lake Powell would add about 200,000 AF each year and rise about 3-4 feet, assuming no additional releases through Glen Canyon Dam. Lake Mead would retain an additional estimated 350,000 AF, which would raise that reservoir by an average of 4-5 feet, not counting any additional inflow from Glen Canyon Dam. In general, Lake Mead would benefit slightly more than Lake Powell from water use reductions.

8. With a 5-year period of water availability even 20% below the 2016-20 average, the outlook for both reservoirs is grim without substantial reductions in water use. Both dams would eventually cease to generate power—Glen Canyon in 2025, and Hoover in 2027. However, a 20% reduction in water use would stabilize both reservoirs and reverse the decline, although that would still not be sufficient to see a real recovery without further cuts or until additional snowpack arrived.

9. With a 5-year period of water availability 5-10% above the 2016-20 average, it would be possible to fill Lake Powell to reach the target elevation of 3588 in 2025, and possibly even in 2024, while replenishing the smaller upper basin reservoirs. Powell could reach 3600-3630, depending on water availability and the degree of reduction in water use. Lake Mead would experience a similar upward trajectory, reaching 1065-1111 depending on water availability and water use reduction factors.

10. With a 5-year period of water availability 20% above the 2016-20 average (similar to what happened in 1996-2000), it would be possible to fill Lake Powell to 3675 in 2027, and with a 5% reduction in water use, as much as 3683. Lake Mead could reach 1124 in 2027.


*****

A key assumption I made in there was that if water use cutbacks are needed (and they are needed), that it be done proportionally among all seven states, and Mexico. It seems to be the most fair and implementable approach, acknowledging current water use realities in the states, and the easiest way to "share the pain". You can argue that approach many ways, and I'd like to hear them, but my rationale was this: the states that use the most water (such as California) would make the biggest cuts in a proportional approach. A 10% cut off 4 maf, for example, is 0.4 maf. For Wyoming, which uses only about 0.42 maf/yr on average, a 10% cut is only 0.04 maf. Not easy for anyone, of course. But that's the point. It's not easy. But it's necessary.

Read the study for the details...
 

The Oracle

Active Member
Liked all you took the time to write JFR...always appreciated, per usual. As you know, the average supply will never meet the average demand without some grotesque changes with regard to demand (the part we stand a chance of controlling?). As you implied, the saddest part is that instead of being proactive, and planning, now we are reacting (which is much more painful). We never learn!
 

Greg Archer 71

Active Member
Both reservoirs would reach dead pool—
I'm not in your league JFR when it comes to crunching the numbers but Dead Pool behind Glen Canyon Dam -- where water cannot flow downstream -- occurs at 3374 which is 160' below where we're at now. You could say we're halfway between full and dead pools. If Powell creeps up to 3540 this WY the BoR will consider that a temporary victory. Cutbacks? Ha. Nothing will happen and they'll head into the next WY praying for more snow. Which likely won't fall. The BoR will continue to juggle the ever-diminishing amounts of water they have to keep Powell functional as a power source and recreational facility. Mead will continue to take the hit so long as it can still produce power down to 950. Nothing will change. This time next year folks will be moaning they can't get on the lake because it's at 3495.
 

drewsxmi

Escalante-Class Member
I'm not in your league JFR when it comes to crunching the numbers but Dead Pool behind Glen Canyon Dam -- where water cannot flow downstream -- occurs at 3374 which is 160' below where we're at now. You could say we're halfway between full and dead pools. If Powell creeps up to 3540 this WY the BoR will consider that a temporary victory. Cutbacks? Ha. Nothing will happen and they'll head into the next WY praying for more snow. Which likely won't fall. The BoR will continue to juggle the ever-diminishing amounts of water they have to keep Powell functional as a power source and recreational facility. Mead will continue to take the hit so long as it can still produce power down to 950. Nothing will change. This time next year folks will be moaning they can't get on the lake because it's at 3495.
By elevation we're halfway between full and dead pools, but by storage we're 26.98% of full pool (most likely calculated versus dead pool). Sadly, I agree that little to nothing proactive will be done this year. Lake Mead is down to one barely functional launch ramp at Hemenway Harbor while the water level is dropping like a rock.

If the long-term precipitation patterns continue, the US will need to think about major adjustments like not growing corn for ethanol, growing food where rain falls, and not trying to make "the desert bloom like a rose." Lack of launch facilities at Lake Mead or Lake Powell would be among the least of our concerns.
 

nzaugg

Well-Known Member
I love boating on Lake Powell, but boating is an ancillary benefit to the dam and dam operations. Nobody would ever have build Hoover Dam or Glen Canyon Dam solely to support boating and recreational activities or even as a tertiary reason. The dams are there for a) flood control, b) to support water delivery to downstream users, c) for power generation, and d) for boating. It is truly meeting the goal of public lands of supporting many uses. If we look at the economic activity Glen Canyon Dam supports, NPS estimates about $500M in benefits from tourism, there is about $150M in power revenue, but the agricultural benefit can easily be measured in the billions, as the Colorado River Basin supports $60B of agriculture, largely based on the support of the water availability provided by Lake Powell/Lake Mead. Agriculture will always be the big dog and is the sole purpose the USBR is operating these massive public works projects.

USBR has done what is necessary to support the biggest economic engine for the basin. We can be upset about diminished recreation opportunity and lake access, which really sucks to be honest, but the impact to my vacation is a lot smaller than the broad economic impact of eliminating or severely reducing agricultural output from the Colorado River Basin. The two lakes have delivered as promised over the past 20 years of extreme drought conditions. They have swallowed up the good years and allowed the impact of the bad years to be severely reduced. The declared shortages of the past couple years in response to reduced available storage have been unprecedented. The way the lake system should be operated is with the storage available in mind as the water allocations are made, with the allocation decided based on current storage and runoff projections. If projections do not meet reality, there needs to be payback over time. This really needs to be looked at as a big bank account, where deficits cannot go on forever, though we all know the federal government is not good at that type of thinking.

Western water law interferes with the ability to make usage cuts mandatory. Every tap on the pipe has a vested interest in using up 100% of their allocation, lest the day of reconning come and the rights be adjusted and their claim be unsupported. The whole of western water law needs reform. It will be talked up during the drought times, but will be forgotten in times of plenty, as it always is. The time to secure funding for these offset projects is now though. The lakes would not be in as bad of shape if reform and improvements in water efficiency were dealt with decades ago. The drought of the early 90s might have made people think about it, but the late 90s made everyone forget. Then again the early 2000s should have made people think, but we grow comfortable in not doing anything.

I appreciate the time you have taken to put together a reasonable plan of action for helping both lakes support all the uses for which they were intended, but when agriculture has a perceived impact 100X greater than all other benefits together, we will have a hard time selling a change in operations. The best I think we can hope for is getting recreation facilities around the lake to support activity at all potential lake levels.
 

John P Funk

Escalante-Class Member
The only thing that will curb water waste is to make it too expensive to waste. The law of supply and demand would indicate that the cost of water should be much higher today than it was in 1984(year of plenty), but I don't believe that is the case. Due to diesel prices I see a lot more fallow acreage than most years, this could mean some water savings(but most of our area is dryland, so no impact to Powell). Irrigation is now expected to end in August(not October). Free market principles are always best, but with so many stakeholders it will be difficult to institute. It's hard to make a farmer in California understand that we didn't get snow in the San Juans, except to make him pay more for his water(or reduce his allotment) in those tough years.
 

Gunny

Active Member
By elevation we're halfway between full and dead pools, but by storage we're 26.98% of full pool (most likely calculated versus dead pool). Sadly, I agree that little to nothing proactive will be done this year. Lake Mead is down to one barely functional launch ramp at Hemenway Harbor while the water level is dropping like a rock.

If the long-term precipitation patterns continue, the US will need to think about major adjustments like not growing corn for ethanol, growing food where rain falls, and not trying to make "the desert bloom like a rose." Lack of launch facilities at Lake Mead or Lake Powell would be among the least of our concerns.
Been preachin this for quite some time. I concur. THE major culprit is ag in the desert. Morons.
 

Trix

Escalante-Class Member
The comments seem to have the underlying assumption that the snowpack has no chance of recovery to above average conditions:

the average supply will never meet the average demand without some grotesque changes with regard to demand
This time next year folks will be moaning they can't get on the lake because it's at 3495
If the long-term precipitation patterns continue

But JFR has identified eight 5 year periods since the lake's inception with at least 5% above normal inflow. And of course we have 2019 with 53 foot rise. Call me Pollyanna, but weather is chaotic and the earth's water supply is fixed. Doesn't mean we shouldn't pursue near term measures to get through this recent drought.
 

Dougie

Well-Known Member
I wonder how it’s possible to monitor water use and measure flow reductions for large agricultural operations. Are there meters that measure water flow for irrigating orchards and big acreages of row crops? Aren’t there large (and powerful) co-ops involved? They would have to be convinced that taking pro-active steps NOW will forestall a catastrophe in 3-4 years (no power generation is likely not a worry to them). Not sure they see dead pool as more than a 10% threat, so would you disrupt your operation with a 90% chance the snow comes back and their sacrifice turns out to be an over-reaction? If reductions are to be mandated, the individual state legislatures of the 7 states need to sign off. We need to avoid executive orders from governors.
 

Dougie

Well-Known Member
Here is an example of ag water cuts imposed in northern utah.

Across Utah, water and canal companies have already made significant cuts in water allotments for farmers and ranchers due to drought. Weber Basin Water Conservancy District has reduced water deliveries to agricultural operations by 40%.
 

Greg Archer 71

Active Member
I wonder how it’s possible to monitor water use and measure flow reductions for large agricultural operations. Are there meters that measure water flow for irrigating orchards and big acreages of row crops?

Drip irrigation works well on a domestic level and saves huge amounts of water. I appreciate there are issues when scaling this system of water delivery to massive acreages of farmland but it can't beyond the wit of man to make such a system viable on a larger scale. Flood irrigation is unsustainable going forwards.
 

nzaugg

Well-Known Member
Drip irrigation works well on a domestic level and saves huge amounts of water. I appreciate there are issues when scaling this system of water delivery to massive acreages of farmland but it can't beyond the wit of man to make such a system viable on a larger scale. Flood irrigation is unsustainable going forwards.
Drip irrigation systems are suitable for large scale systems depending on the crop. It works well with trees, vineyards, etc, but not with grains, corn, alfalfa, etc. Central pivot irrigation has resulted in major water savings and big boosts in productivity versus flood irrigation.
 

ndscott50

Active Member
Instead of sending $40 billion to a foreign country, maybe we could spend just ONE billion, and build a water pipeline from the Mississippi to the Southwest to alleviate all of our water concerns. But that's just crazy talk....
There is a proposal to build a pipeline to move green river water 338 miles to the front range. Its generally down hill and only provides 55,000 acre feet. The estimated cost is $2.3 billion. In order to alleviate all our water concerns we would need to add a few million acre feet per year to really make a difference. Its 500 miles to the Columbia or 800 miles to the Mississippi and also up hill.

You are probably looking at minimum $40 billion per million acre feet for a pipeline like that - likely more. In todays dollars the Apollo Program was about $200 billion. Probably need something along those lines. Also don't forget the cost to operate and maintain which would be substantial.
 

Eagle Rock

Active Member
Instead of sending $40 billion to a foreign country, maybe we could spend just ONE billion, and build a water pipeline from the Mississippi to the Southwest to alleviate all of our water concerns. But that's just crazy talk....
Yes, at $1 billion it IS crazy talk. As ndscott50 already pointed out,you're looking at more like $100 billion to get pipeline capacity equal to 1/3 of the 7.5 MAF/year the upper basin wishes it had. And then you have to pay for pumping and maintenance. And that's assuming the Mississippi River water rights holders will let you have a few million acre-feet every year for free.
 
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