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Lake Mead Water Level to drop to historic lows 4

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bimr

Civil/Environmental
Feb 25, 2003
9,308
US
Potential double whammy; Reduced water supply and power.

The man-made lakes that store water supplying millions of people in the U.S. West and Mexico are projected to shrink to historic lows in the coming months, dropping to levels that could trigger the federal government’s first-ever official shortage declaration and prompt cuts in Arizona and Nevada.

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The Bureau of Reclamation also projected that Lake Mead will drop to the point they worried in the past could threaten electricity generation at Hoover Dam. The hydropower serves millions of customers in Arizona, California and Nevada.

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This is not surprising.

California sticks a pretty big straw into the Colorado River, and the Southwest (CA, AZ, NV, UT) continues to grow.
Between 1970 and 2020, California's population alone has approximately doubled from 20M to 40M.

Planning for this growth, USBR and California state officials have doubled their water storage in the few decades to keep up with population growth and farming demand. Actually, no, that was just satire.

I'm not sure how many new reservoirs larger than 0.25 MAF have been built in the West in the last 30 years, but I think it is close to zero. I'm ready to send a fresh cheeseburger to anyone who can name 3 reservoirs built in CA larger than 250,000 Acre-Feet. For comparison, Mead is 30M Acre-Ft. To be fair, there have been reservoir modifications to make dams and levees around reservoirs taller and larger (and more dangerous), but scarce new work.

No doubt climate variations are a major source of the problem as well. Which is why you'd think that California would be building more reservoirs, to account for the worst-case projects based on climate change modeling. But instead, we talk about climate change. And talk. And weep. And the population grows... This is more like a self-inflicted wound.
 
This was the last time I was at Hoover Dam/Lake Mead, eight years ago. I imagine that the lake level is much lower now than it was back then:

JE-030_dofv9v.jpg

September 2013 (Sony A65)

This shot is from the first time we visited there. You can see that the level of the lake was much higher back in 1989:

CA-095-4_rj6ukm.jpg

December 1989 (Minolta XG-M)

Note that as of today, here in SoCal, we've had only 4.39 inches of rain so far this season (since October 1st). Normal season-to-date is 12.86 inches. They are predicting rain for next week, but I'm not holding my breath.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
More fires? Climate change is a b*tch...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Nobody much cares until they realise they just got their last drop. The western US has had desertification risk warnings for a long time. I thought that was why they called them "red states".

800px-Desertification_map.png
 
If the climate forecasting models are correct and future seasons will produce more extremes for precip, wouldn't that argue for more reservoirs?
If the demand on water resources doubles, would you be surprised if the water system appears to be fragile?
Even in successive wet years, Mead has been low. Demand keeps growing, but reservoir capacity does not. Of course the lake will be tending to lower average elevations. You don't even need to invoke climate change.
There's an engineering solution for this. Build more reservoirs, don't send quite so much water to the ocean, and double down on conservation. Yes, there are environmental impacts that must be dealt with, but they are all manageable.
The alternative is to keep doing what we've been doing: not expanding the water system proportionate to the demand.
 
True, but there is an alternative, which may not be optional. If they don't build more catchment, the population of the region will be forced to migrate elsewhere. That's what happened in Guatemala. No more reservoirs needed to catch water that ain't getting there anyway. Canada looks promising.
 
The drought conditions in California exacerbate its demand for Colorado River water, but that's compounded by unusually dry conditions all along the river, so there's less water to start with. I don't think there's much in the way of river flow into the ocean in California; we're probably going to need to dig cisterns and have rain catching roof and pavement structures to catch the water that goes down our storm drains.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
As a child, when we lived in Morris, Manitoba, both my parents and grandparents had 'carbon filtration' boxes that caught the rainwater from the roof, filtered it and stored it in a large concrete cistern. This was the water we used to live on... I've not been able to determine how the filter boxes worked... they were attached to the side of the house and how they were made, or how the system worked. They were built by my dad and grandfather and his brothers... they've all passed on. It was so neat.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Roof drainage requires sediment and carbon absorption filters, followed by disinfection as the roof drainage may be contaminated with bird feces.
 
We need to invest 100 years worth of energy and resources in to reconstructing our entire energy grid over the next 20 years in order to prevent climate change that was triggered by the first 100 years.

The other side of these stories is that the seemingly catastrophic levels we have reached have precident in recent history. 1977 was the most recent serious drought event. The difference may be that the population is larger. There certainly hasn't been investment in water storage infrastructure. The climate change doomsayers won't allow that.
 
Like I said, no point building storage for what you don't have and aren't anticipating to be receiving in storable quantities anytime soon. I've heard for years and years that many existing western region dams were planned and constructed based on relatively sparse data which may have contained a significant number of wet years in the database and that was well before anyone was concerned with CC. The map above would not indicate that more favorable data is in the cards. How can you justify building dams with that map. That map needs some desalination plants. Start with Salt Lake City and don't stop.

One reason I bought a house where I did was the red zones I saw on that map. When I lived in Riyadh, rotating water cuts were/are a fact of every day life. Not ideal to plan your activities around what days you can wash the clothes. We washed the car with diesel. It was cheaper than water.
 
California sends more than half of its water to the Pacific Ocean. [As much as we love the Colorado River, we get our water from many sources.]
In the years where we (I am from CA) have more than average precip, we send even more water to the Pacific. Snowpack and cool spring temperatures are our main "reservoirs."
There are a few big reservoirs - notably Oroville - and of course many smaller ones - but in years where the reservoirs get full by May - yes this still happens - zillions of gallons of water must be released out of the reservoirs. The State Water Project can only handle so much flow in the Aqueduct.
I am a structures guy, but have water records for a large watershed in Norcal from 1900 to 1960. What you see in those 60 years is what you see today: Extreme fluctuations in precip from year to year. Even before NASA engineers was warning about global cooling or global warming. While I cannot provide a good mathematical comparison between the previous period and the last 30 years, graphically the variation looks similar for the last 120 years.
That's why the State Water Project was built in the first place (1960s to early 1970s). Reservoirs will not solve every problem. Storage = options. Limited storage = California.
However, political reasons, not engineering reasons, are why we are in a pickle today.
 

John Weber's plan would do be to build two earth and rock dams across the narrow necks of the upper and lower bay, one from San Francisco to Oakland, one from Richmond area to Marin. The dams would have been broad enough to carry all the traffic that would ever crossed the San Francisco Bay, including main line railroads rapid transit lines. Fresh water flowing flown from the river through Carquinez would have soon flush out the salt water above the northern dam and make that part of the San Francisco Bay a fresh water reservoir. From there a ship canal would carry river water down the east shore to the area below the San Francisco Oakland Dam, making a second fresh water lake.

Thus, said Reber, California’s urgent water problem would be disposed of forever by conserving at least one third of the tremendous volume of fresh water which now rushes down from the Sierra to the San Francisco Bay and wastes out the Golden Gate. The San Francisco Bay Area would had at its doorsteps reservoirs with a total surface area greater than any man-made lake on earth, constantly replenished by the river, “with all the water the state can ever use,” said Reber, “free for the pumping.”

 
Of course there were some unintended consequences that resulted from the California State Water Project and the aqueduct system that brought water to Los Angeles and the rest of Southern California. Note that while rice had always been grown up in the Sacramento River delta region, even before many of the dams and reservoirs were built, the rest of the Central Valley depended on farming that required less water. However, the aqueduct system changed all of that since the system was basically being paid for, including the cost of the water itself, by the people and industries in the Southern end of the state, and so the big agribusiness that sprung-up in the Central Valley took full advantage of what for them was basically 'free water'. Suddenly they could grow anything wanted and since water was not an issue, the were no longer limited to water-friendly crops. BTW, do you know how many gallons of water it takes to grow a single Almond? The first time I ever drove up the Central Valley, in 1980, when you came down off the Grapevine, as far as the eye could see was fields of Cotton, one of the least water-friendly crops one could grow, but since the water was virtually free, why not. Cotton earned you a lot of money per acre.

Of course, when the droughts stared to really hit the state, they started to make noise about getting EVERYONE in the state, including farmers, to actually pay for the water that they used. Note that it was only about 15 or 20 years ago that people living in the Sacramento area even had water meters at their homes and businesses. They were simply charged a flat rate depending on the size of the property or the type of business one was running. There was NO incentive to conserve. But those of us in SoCal had to stop washing our cars or watering our yards, and trust me, we had always had water meters and we paid penalties when we went over our 'allotment'. In fact, one year they were fining people $500/day if they failed to turn-off their sprinklers for at least three days after a rainfall.

Of course, when the big agribusinesses got word that they were going to have to actually pay for the water that they were using, you'd of thought that we'd been invaded by Communists, which was strange since it was the farmers who had been enjoying what was basically 'socialism' for all those years. And of course, it didn't help when someone who was running for President in 2016 came to the state and promised the poor farmers (actually the big agribusinesses) that is elected, he would make sure that water would continue to flow and that he would declare the drought over and put things back the way they were before the 'liberals' stole all of THEIR water.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 

I think there was a carbon filter (activated carbon, I doubt) and a sand filter, but that's it... I don't know or recall if we had a well, but I don't think so.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
A few sample daily hydrographs from the 1920s and 1930s in Northern California. Attached and pasted below. You need young eyes to read the print, but you can seen extreme variation from year to year, not just in daily inflows but total precip in this particular watershed. Yes, I am being vague on purpose, but all of this is legit.
In fact, these should be public records thru Calif Natural Resources Agency, but in reality, it helps if you've worked as a consultant for the State, or know somebody on the inside.
Daily_Hydrograph_Norcal_1920s_as3jdg.jpg

Daily_Hydrograph_Norcal_1930s_lrrfnc.jpg

 
Thank you.
It sure is all over the place.
Is there a correlation to El Niño?
 
About 60 years ago, there was a cluster of these new, larger dams being built or enlarged, as well as smaller stream storage.

Our family was involved in some of the smaller projects.

They knew the the variability of the seasons and they saw the need. It was always conceived as 5+ years of carryover storage.

The more demand you place on the system, the less years of carryover you can count on.

Those charts were what I was told in words but they basically bear out my understanding of it, in general.

Now just wait for the aging infrastructure to have a real bad failure and see what gets done after that. Oroville was mercifully mild but who knows what is lurking at several very large structures around the state.
 
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