Challenges with capturing and storing rainwater for drought in California
npr.org
npr.org
[1] https://www.waterworld.com/home/article/16222295/gov-schwarz...
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?
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....
Disclaimer: I know very little about dams. But it has been done:
https://www.denverwater.org/grossreservoir/construction/rais...
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 water level is still at an historical low, does the rain hit its watershed?
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.
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.
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.
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."
(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.)
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.
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.
If anyone suggests a better title (i.e. more accurate and neutral, preferably using representative language from the article), we can change it again.
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.
“California’s reservoirs full early in rain conveyor whatever it’s called now”
Ie. tell them they met their goals early!
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