[1] https://upload.wikimedia.org/wikipedia/en/a/a2/Sierra_nevada...
[2] https://en.wikipedia.org/wiki/O%27Shaughnessy_Dam_%28Califor...
"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.
https://www.baycitizen.org/news/water/raise-rent-hetch-hetch...
(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.)
More info: http://www.sfwater.org/index.aspx?page=391
A few facts, with sources:
- The water coming out of Hetchy Hetchy is still well within the 'usable' range [1]
- The total loss of power is 293 MW (Holm and Kirkwood), which is a tiny percentage of the power generated in CA [1,2]
- The SF PUC is already dealing with the loss of those 293 MW: San Francisco is making up the difference in power generation by accessing power in an existing power bank and purchasing power on the open market. [1]
- PG&E is reporting no problems in their network (at 10:20 PT) [3]
Keep calm, carry on. Perhaps take it as an opportunity to turn of the lights you're not using, like you should every day ;)
1. http://www.sfwater.org/index.aspx?page=711 (see chart) 2. http://en.wikipedia.org/wiki/List_of_power_stations_in_Calif... 3. http://www.pge.com/en/myhome/customerservice/energystatus/gr...
For example, 74% of Mountain View's water comes from Hetch Hetchy. (They get 87% of their water from the SF Public Utilities Commission, and 85% of that comes from Hetch Hetchy.) [1]
Daly City, San Bruno, and South San Francisco currently get 67% of their water from SFPUC and the rest from local aquifers, with a project in the works to increase the SFPUC portion to 100%. [2]
Palo Alto, Menlo Park, and other towns also rely on it, although I don't know the percentages.
Many have seen the pipeline that crosses the Bay between the Dumbarton Bridge and the old railroad bridge.
There are also a number places in the Peninsula and South Bay where you can see parts of the Hetch Hetchy Aqueduct, either the pipes themselves or the above-ground access hatches where the pipe is underground. These are white structures, often circular.
For example if you walk or run the Dish Trail at Stanford, you can see a number of these next to the northernmost part of the trail. This is part of the southern branch of the Aqueduct, which doesn't cross the Bay but cuts south through Milpitas, Sunnyvale, and Mountain View.
Several places where you see a residential street that is divided with a very wide grassy or dirt median, that's the Aqueduct: Sharon Heights Drive and Ivy Drive in Menlo Park are examples.
Along Edgewood Road near 280 there are a number of pipeline sections where it alternates between above-ground bridges and underground sections through those hills. The pipeline then parallels the Cordilleras Trail in the Pulgas Ridge Open Space Preserve where you can see some of the access structures.
On the other side of 280 on Cañada Road there is the famous Pulgas Water Temple [4], where you can really get a sense of how much water flows through the Aqueduct.
For the obsessively curious like me, several years ago I traced the path of the southern branch of the Aqueduct and made a KML file marking some of the visible structures. [3] Someone else had made a similar file for the northern branch but I don't know where to find that now.
[1]: http://www.mountainview.gov/city_hall/public_works/water_con...
[2]: http://www.sfexaminer.com/sanfrancisco/three-peninsula-citie...
[1] Liquid Fluoride Thorium Reactor
If you mean "protect these units from bad guys so they don't steal the thorium and weaponize it," that's one of the great things about thorium reactors: thorium and its byproducts are very hard to weaponize. [1]
[1] https://en.wikipedia.org/wiki/Liquid_fluoride_thorium_reacto...
If you have a lot of units, the loss of one or a few has limited effects, vs. taking out a few big baseline power plants and/or major transmission nodes.
What's the local/regional cost if someone takes out a node with a sufficiently big shaped charge?
I am pretty sure there are lot of challenges within the project, but I can envision drones working together to connect each other and transport water to sprinkle it when needed without humans being endangered. I mean, if we achieved this [1], why not go further?
I'm not saying its insurmountable, just that it's way beyond the current levels of both drone technology and acceptance.
Instead of huge drone carrying water (we already have planes to do that now), I was envision a network of connected drones that "pass by" the water as they hover in the line all the way from water pool to fireplace. The video attached previously shows you group of drones perfectly communicating with each other.
I never said it was easy to develop, but I have to disagree its something "way beyound the current levels" of technology. Further, the cost to design, develop and implement would be pennies comparing to an average damage of mid-size fire. Not the mention about life-loss.
Heck just a temporary prolonged outage of Google alone would have huge negative consequences for the US (not to mention the world). Amazon AWS US west is in Northeren California. I wonder how big the negative effect will be on just how many companies?
Google, Facebook, LinkedIn, Y-Combinator, Stanford, Yahoo, etc are all located in the South Bay and (may or may not be, the article doesn't specify) affected by the fires.
This report is an economic scenario analysis, and estimates the probable effects on the Bay Area economy of a major failure of the San Francisco Public Utility Commission’s Hetch Hetchy water system,
http://www.bayeconfor.org/pdf/hetchhetchyfinal2.pdf (map on pg 4)
https://www.google.com/maps?ll=37.47579%2C-122.1629239999999...
(You may need to zoom out; I couldn't figure out how to save a URL with the correct zoom level.)
Don't believe your own hype. It's bad for you.
I've no idea if it lives up to its own hype.
The strategy for containing these fires is typically fuel deprivation, rather than "flame extinguishment" which is so difficult if not impossible for the above reasons. The guys that jump out of planes to fight backcountry fires, for example, are armed with axes and saws. Absent something like a star-wars (AT-AT) its not clear a direct frontal confrontation is pyhsically feasible, even from the air, for many fires.
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.
You make things because they are interesting to make, and could have a positive impact in the world. Protecting yourself from "the bad guys" is a secondary (or even tertiary) concern, unless the very purpose of the thing is to protect people from bad guys (for example a military fort).
Sure, the U-232 contaminated U-233 is nasty, but as long as it doesn't make it impractical to make a nuclear warhead it's quantitatively different from the uranium cycle, where after a few months at most plutonium is impossibly contaminated with two even more undesirable isotopes (one is very hot, I've seen estimates of 100kW for a bomb sized quantity (it's used for RTGs in deep space probes), the other precludes much of a bang and required the Manhattan Project to go with an implosion design).
Despite the gamma ray emission drawbacks, it could still be the easiest way to get lots of weapons grade fissionables from civilian power plants.
Reduces to a protoactinium problem, it decays to U-233 with a half-life of 27 days. The article claims there's so little protoactinium in the total mass of salt and stuff that it's not practical to isolate it, at least not without detection, and failing that, not quickly. This gets into fine details beyond my level of expertise, but I agree the problem is much reduced. Although very possibly still greater than for current LEU designs.
Solid thorium reactors mix Th with the existing waste piles of Plutonium sitting in cooling pools and burn that up for us[1].
There's no waste materials to release from either of these reactors.
[1] http://www.extremetech.com/extreme/160131-thorium-nuclear-re...
These reactors by definition have a fair amount of very "hot" materials; it hardly matters if none of them are declared "waste" if they'll still kill you in a few minutes of direct exposure.
There could be a risk of contamination from the cooling loop, but such contamination might even be less than the normal radioactive fallout from the flues of coal plants.
The radioactive fuel is a molten salt, so it will cool and solidify soon after dispersal. It is certainly not good, but is it really worse than say, a chemical plant?
The radioactive stuff won't remain airborne after the initial blast, so that means a predictable and small area to remediate.
The fuel dispersed in an explosion can be collected, since it will solidify, so it won't poison the water table.
While not perfectly safe (nothing is), the disaster contingencies seem fundamentally different and better than those from a PWR + solid nuke waste disposal site.
There would be many more of them, which is both good and bad for various cases.
Petrol from a tanker? Shaped charge.
Cracking armored vehicle? Shaped charge.
Unlocking stuck door? Shaped charge.
It really does seem people try to downplay any potential reactor designs because global thermonuclear war may damage the reactor. Stop living in fear.
molten salt reactors (the kind in the comment at the top of this thread) are at atmospheric pressure, and are designed with a drain plug which isolates the (very hot) materials from the neutron source, after which they cool down happily on their own in a separate but similarly shielded compartment.
release of materials is one of the most unlikely outcomes ever.
(Which is relevant in the context of massive distributed ones; current nuclear power systems mitigate this by being few in number such that they can be well guarded.)