[001sky]

For anyone wondering what the relationship between wildfires in Yosemite and San Francisco proper, its worth a small comment. California's Sierra Nevada range is a couple hours east of SF. These mountains include the highest points in the continental US. Trapping most of the water from the east-west jet stream. The sierras hold massive amounts of high-quality water, which runs out of the non-porous terrain of the high-alpine regions. The sierras are something of a geological monolith, not unlike a giant bathub [1]. SF taps into this water source at a dam on the West; LA taps into it on the East (LA acqueduct). This fire is threatening the a region about an hour or so north of Yosemite Valley, and west of Tuolome Meadows, where some critical infrastucure resides.[2]

[1] https://upload.wikimedia.org/wikipedia/en/a/a2/Sierra_nevada...

[2] https://en.wikipedia.org/wiki/O%27Shaughnessy_Dam_%28Califor...

[hga]

Yikes! From the article:

"The Associated Press says San Francisco gets 85 percent of its water from the Yosemite-area Hetch Hetchy reservoir that is about 4 miles from the fire."

The fire is well established now, and in addition to the threat to the water supply they've already had to shut down electric transmission lines.

[hkmurakami]

I remember talking to one of the rangers at Yosemite, near one of the natural lakes that eventually supply water to SF. I remember him saying that he tells visitors who go answer nature's call at the lake to think twice, since they're going to be drinking this very water soon.

[fnordfnordfnord]

What did he say about drinking fish shit? And the effluent of every other critter in the park?

[pyre]

I think that it has more to do with the idea that humans moving through that area would do much more damage (than the local animal population) if they were not discouraged in some way.

[fnordfnordfnord]

Rangers should discourage people from fouling the area, but the comparison made by the Ranger is nonsensical on a number of levels. Anyone who heard it might disregard it after recognizing how silly an argument it was.

[cdash]

Just as astronauts on the ISS drink their own piss, it is nothing but in our minds.

[pyre]

Drinking your own piss is different than drinking someone else's piss. :P

[mapt]

Urination is a relatively low-impact activity on a water supply. Defecation, on the other hand, tends to cause a decent variety of diarrheal illnesses unless the water treatment facility is quite good - something that may not be accurate for something designed for sterile snow runoff. The water here is not just being drunk, but going on fresh produce as well, so you can't rely on purely municipal filtering.

[bavcyc]

The SF water supply has some interesting politics:

https://www.baycitizen.org/news/water/raise-rent-hetch-hetch...

[nknighthb]

Water is intensely political pretty much everywhere but rainforests, and at all levels of government. However, unless you're directly involved, you don't hear about it because it can't normally be used as a political football. Your opinion on any particular water dispute will have nothing to do with your political views or party affiliation, it's mostly a product of geographic location or industry, and no politician who happens to represent both parties wants to take sides. (And any politician who represents only one side will invariably adopt that side's position.)

(Incidentally, in the modern era, the US Supreme Court's original jurisdiction case load is made up almost entirely of states suing one another over either water rights or boundary disputes based on rivers.)

[mapt]

We're not quite Mad Max yet. Perhaps 80% of the country lives in an area where water is not scarce enough to prompt water table depletion or aqueduct building. "Water politics" in these areas mostly consist of bureaucratic squabbles regarding the minor expense of water treatment facilities & pipe-building, or soft-science environmental debates about erosion, fish, and effluents - things which can be reliably consigned to the higher end of Maslow's Pyramid.

About half of the remainder of the problem could be solved easily by ending this stupid obsession for English Country Manor lawns well outside a climate zone where they're viable, and prohibitions on all but drip irrigation for agriculture. These could be mostly accomplished without legislatorial nitpicking by simply making prices reflect scarcity, permanently. We seem to have an innate resistance, politically, to pricing water to reflect its infrastructural and depletion-replacement cost, to admitting that some mechanism needs to scale back use.

Some issues are simply not solveable, it's true - isolated water tables that have been changed by taprooted invasives are probably never going to revert to grassland, and need total cessation of irrigation activities to avoid desertification. These cases are relatively rare though.

[hga]

I've read that when California's major water systems were built long ago there were explicit compacts between the urban and agricultural regions. The latter now see various actions as breaking that.