Challenges with capturing and storing rainwater for drought in California(npr.org)
npr.org
Challenges with capturing and storing rainwater for drought in California
https://www.npr.org/2023/01/07/1147494521/california-weather-storm-water
51 comments
The reason is California lacks infrastructure to collect rainwater. Rain hitting urban areas mostly heads out to the ocean or into the sewage network. The tech and engineering know-how to collect and recycle storm water at scale is available-- Singapore does a great job at this.
California farmland lacks the technology to collect rainwater. If you catch the water high in the watershed you don’t have to deal with the deluge at the bottom. Also ground water can end up being aquifer water.
Terracing is an ancient technology that turned arid land into gardens.
Indeed.
There’s a book out of copyright for a few decades called Farmers of Forty Centuries which tries to answer the question of “how is it the Chinese haven’t destroyed their fields in 400 years like we have?”
A lot of it is the slowing of the water, but also harvesting silt from the rivers and canals to build up material and keep the waterways from silting up.
A question I’ve had since reading that book is what has happened since the industrial revolution? Did manufacturing effluent break that process, and if so how extensively? Only in the deltas or how far upriver?
There’s a book out of copyright for a few decades called Farmers of Forty Centuries which tries to answer the question of “how is it the Chinese haven’t destroyed their fields in 400 years like we have?”
A lot of it is the slowing of the water, but also harvesting silt from the rivers and canals to build up material and keep the waterways from silting up.
A question I’ve had since reading that book is what has happened since the industrial revolution? Did manufacturing effluent break that process, and if so how extensively? Only in the deltas or how far upriver?
In November 2014, California voters approved Proposition 1: The Water Quality, Supply, and Infrastructure Improvement Act. The $7.5 billion bond dedicated $2.7 billion for the public benefits of new water-storage projects.
But no new reservoirs have been built. This may or may not be changing now [1].
[1] https://www.mercurynews.com/2022/02/10/opinion-voter-approve....
But no new reservoirs have been built. This may or may not be changing now [1].
[1] https://www.mercurynews.com/2022/02/10/opinion-voter-approve....
My understanding is they went pretty gung-ho building them and there aren't great spots left and new ones would severely disrupt or destroy entire ecosystems, like damming the Klameth.
Maybe you could just make the existing dams higher? That way, a lot of the new water sits on top of old water, and the undammed rivers continue to flow.
Disclaimer: I know very little about dams. But it has been done:
https://www.denverwater.org/grossreservoir/construction/rais...
Disclaimer: I know very little about dams. But it has been done:
https://www.denverwater.org/grossreservoir/construction/rais...
If you build on top of an existing dam, the whole thing needs to be stronger top to bottom, the water pressure at the bottom increases when you add water on top. Sure there are places where this is possible but not everywhere.
Plus the existing reservoirs aren’t full ever, what’s needed is new watersheds to capture new water (or to use less, etc)
Making existing dams taller just adds empty space.
Plus the existing reservoirs aren’t full ever, what’s needed is new watersheds to capture new water (or to use less, etc)
Making existing dams taller just adds empty space.
The sites reservoir looks like it will be built finally.
For a little bit of fun history:
https://en.m.wikipedia.org/wiki/California_water_wars
https://en.m.wikipedia.org/wiki/California_water_wars
What is happening at lake Mead?
The water level is still at an historical low, does the rain hit its watershed?
The water level is still at an historical low, does the rain hit its watershed?
https://mead.uslakes.info/level.asp
Looking at past years it seems to usually go up a bit this time of year. It's going to take much more to get back up to levels of past years. 2019-2022 this time of year had a sharper increase than it has now.
Looking at past years it seems to usually go up a bit this time of year. It's going to take much more to get back up to levels of past years. 2019-2022 this time of year had a sharper increase than it has now.
Here's a nice, simple chart of the current state of California's reservoirs. There's currently a lot of room for rain and more water, with most of them far below historical averages, (and even farther below capacity)
https://cdec.water.ca.gov/resapp/RescondMain.
However, when you look a charts on a single reservoir, you can see that the rain is making a clear increase in water levels.
https://cdec.water.ca.gov/resapp/ResDetail?resid=SNL
https://cdec.water.ca.gov/resapp/RescondMain.
However, when you look a charts on a single reservoir, you can see that the rain is making a clear increase in water levels.
https://cdec.water.ca.gov/resapp/ResDetail?resid=SNL
I wonder if the problem of aquifers not getting filled up can be planned for in future cities. Covering huge swaths of land in concrete is great for vehicles but really not great for flood prevention: if water can’t go into the ground, guess where it’s going? Your basement!
A solution used on one street in Seattle is to have the drainage ditches on the side of the road have places where the water can slow down and soak into the ground.
Places where it rains have vast storm sewers and you only get flooded if you build in the wrong place. Streets, parking lots, basements are all drained.
I'm sure the fact that trying to build such an infrastructure can be construed as anti-environment plays some part in the lack.
This headline format really needs to die.
There's no story here beyond 'California's reservoirs are not sufficiently large to offset all water losses from drought, or to capture all rainfall during flood weather.' It's great clickbait because the same story is likely to be true under almost any conceivable range of circumstances.
There's no story here beyond 'California's reservoirs are not sufficiently large to offset all water losses from drought, or to capture all rainfall during flood weather.' It's great clickbait because the same story is likely to be true under almost any conceivable range of circumstances.
Get a grip. I'm a Brit so 7000 zillion miles away from CA. The title says x is an issue and the article tries to answer it. I'm reading stuff about somewhere else and why not? CA is famously in a long term drought and yet it is being short term very heavily rained on. I cannot fault the article title - it is a very obvious question.
This seems pertinent:
"Some of it can be captured for later, but the short answer is it falls so quickly that we lack the ability to take that water and set it aside quickly enough in a place where we can store it for later. The primary forms of storage for water in California are the snowpack, that typically accumulates annually, and then reservoirs behind dams, and then groundwater aquifers."
This seems pertinent:
"Some of it can be captured for later, but the short answer is it falls so quickly that we lack the ability to take that water and set it aside quickly enough in a place where we can store it for later. The primary forms of storage for water in California are the snowpack, that typically accumulates annually, and then reservoirs behind dams, and then groundwater aquifers."
Can you please omit swipes like "Get a grip" from your HN posts? This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html, and your otherwise fine comment would be much better without that bit.
(I realize things like that aren't cardinal sins or anything but they poison the ecosystem in a way that doesn't automatically self-correct the way it can in smaller groups or more private forums. On HN it makes a big difference when commenters throw these things in vs. restrain themselves from doing so.)
(I realize things like that aren't cardinal sins or anything but they poison the ecosystem in a way that doesn't automatically self-correct the way it can in smaller groups or more private forums. On HN it makes a big difference when commenters throw these things in vs. restrain themselves from doing so.)
Message received.
The existing reservoirs are, generally, nowhere close to full. https://www.sfchronicle.com/weather/article/Here-s-where-Cal...
Looking at the contents of the interview, the problem looks more to be in aquifer recharge. Also probably runoff, and nitrogen pollution (especially, but among others) I bet.
Looking at the contents of the interview, the problem looks more to be in aquifer recharge. Also probably runoff, and nitrogen pollution (especially, but among others) I bet.
But is it about the average state of the reservoir or the extreme case of catching (all) the water you get during unlikely but intense weather events?
I’m not sure what you mean. The reservoirs tend to sit at a watershed’s egress point, runoff is obligated to pass through it. If there’s ample room in the reservoir, no runoff is lost.
I think a correct reading of the article, which is perhaps too oblique on this point, is the loss of water to runoff where it is not in a watershed with a major reservoir, and not able to infiltrate into the aquifer. Add some runoff, such as agricultural runoff, is heavily polluted, complicating the matter even more.
I think a correct reading of the article, which is perhaps too oblique on this point, is the loss of water to runoff where it is not in a watershed with a major reservoir, and not able to infiltrate into the aquifer. Add some runoff, such as agricultural runoff, is heavily polluted, complicating the matter even more.
Ok, I've attempted a neutral title using language from the article that will satisfy your and the different commenters' criticisms here.
If anyone suggests a better title (i.e. more accurate and neutral, preferably using representative language from the article), we can change it again.
If anyone suggests a better title (i.e. more accurate and neutral, preferably using representative language from the article), we can change it again.
Really, I don't mind it being posted on HN (even though I think the article is clickbaity). If anything, changing the title obsures the issue because readers won't see it as the clickbait it is.
There are fashions in headlines like anything else. Two very popular fads at present are 'X is a given fact, so why doesn't obvious corollary Y obtain?' and 'No, X isn't actually Y'. If I run across an article like this, I'm reluctant to submit it to HN because it's usually a low-quality piece of writing, and there's usually a better-quality that will appeal more to a technical audience.
There are fashions in headlines like anything else. Two very popular fads at present are 'X is a given fact, so why doesn't obvious corollary Y obtain?' and 'No, X isn't actually Y'. If I run across an article like this, I'm reluctant to submit it to HN because it's usually a low-quality piece of writing, and there's usually a better-quality that will appeal more to a technical audience.
That's way too long of a headline. And if it was just "California's reservoirs are not sufficiently large", or something, doesn't that imply that they should be increased in volume?
How? Reservoirs take up enormous amounts of land, are ecologically disruptive and increase flood risk, especially if the embankments are allowed to dry out during times of drought.
After a week of storms the reservoirs had moved from 33% full to 34% full. It's not that they aren't large enough, it's just the watersheds that lead into them aren't particularly large relative to the state. I lived near Berryessa and yes it raid from a low of 394 on Dec 20th to 399 today. It's still 40 feet under the spillway, which I've seen activated before.
Take a positive spin:
“California’s reservoirs full early in rain conveyor whatever it’s called now”
Ie. tell them they met their goals early!
“California’s reservoirs full early in rain conveyor whatever it’s called now”
Ie. tell them they met their goals early!
They are far from full: https://cdec.water.ca.gov/resapp/RescondMain
I read the short article and your summary.
Your summary is terrible and misses several details
1. The reservoirs are already full 2. Not all the water can be channeled as ground water because of water quality and throughput issues 3. The primary sources depend on slow melting of the snowpack. But the water is coming in too fast to form a snow pack and gets washed away
Your summary is terrible and misses several details
1. The reservoirs are already full 2. Not all the water can be channeled as ground water because of water quality and throughput issues 3. The primary sources depend on slow melting of the snowpack. But the water is coming in too fast to form a snow pack and gets washed away
Far from full: https://cdec.water.ca.gov/resapp/RescondMain
There are full reservoirs:
“ And the challenge is that when we get a lot of rainfall like this, it's not forming snowpack in lower areas. And reservoirs tend to fill up rather quickly. Then we have aquifers, and they have space, but it's hard to get water where it needs to be so it can infiltrate into the ground. And even then, it's hard to get it in fast enough.”
They are not close to full.
This story is a perennial favorite that is trotted out every time it rains heavily enough to cause flooding. I also agree the headline format sucks because it's lazy clickbait format.
It feels like the journalist is channeling the guy from the xkcd.
https://xkcd.com/793/
https://xkcd.com/793/
He’s not wrong tho. A nuclear explosion would blow the water back into the atmosphere as vapor where it will cool with fallout and join the snowpack. Just add potassium iodide to the municipal water supplies. Putting “challenge” in the headline is pure clickbait.
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burlesona(3)
[1] https://www.waterworld.com/home/article/16222295/gov-schwarz...