"The abandonment of a city like Los Angeles, would be just as quick as say New Orleans was if the taps ran dry. i.e. about a week."

For Las Vegas and Phoenix, probably half that.

The crux of the problem is our high water usage. The U.S. national average of water usage is 180-200 gallons per person per day. Even at the lower estimate, for a family of four, that is over 250,000 gallons per year, or 20,000+ gallons per month.

Rainy Seattle gets about 36" of rain per year; if that arrived evenly at 3" per month (it doesn't), that's still only 1860 gallons for a 1000sf house, 3720 for a 2000sf house, and 4650 gallons for a 2000sf house with a 500sf garage, with a grand total annually of 55,800 gallons per year. That provides 4650 gallons per month, far short of the average use, and would provide a maximum of 38 gallons per person per day, far short of that 180 gallons.

During the recent election, one of the arguments against our state government was that "it doesn't have an income problem, it has a spending problem". With water, we have a usage problem.

Just for fun, I did a little basic math for a city in SoCal, picked at random, Canoga Park. It's average rainfall is 16.83"/year, mostly falling in 5 continuous months (Nov-Mar), the other 7 months are almost dry.

If you had four people living in a 1000sf house with a 500sf garage, you might be able to collect 15,000 gallons of water.
At the usual water usage of 180 gallons per person per day, that 15,000 gallons would last about a full 20 days.

If you rationed it to 50 gallons per day (12x4)*, it would last about 300 days. If you could ration it to about 10 gals per day per person, you might be able to squeak through a good year. Otherwise, you would have to create enough additional collection area to make up the 3,250-gallon shortfall. And that's a decent year, and that's paring it awfully close to disaster.

*****
According to Population Reports the four most basic water needs are for drinking, sanitation, bathing and cooking. Worldwide, the estimated average need is 12 gallons per person per day.

Sue

Not to mention you'd need a foolproof storage system to avoid contamination, evaporation, etc. And what about growing food or raising animals? Cause any area thats devoid of water is also devoid of economic investment and commerce. Which means you'd have to be pretty self sustaining. Water = economic development.

Your water calculations for collecting from a house are way high. Your average house closer to town is not a single floor ranch so that 1500-2500 sq ft is divided in half for two stories or a third if the city/county or realtor counts the basement as living space. Then of course use Pythagorean theorem to adjust for the angle of the roof but its your still going to get way less water

Move.

Invest in water-from-air technology. http://en.wikipedia.org/wiki/Atmospheric_water_generator

Support water conservation and recycling.

Support family planning.

Support politicians who support the above.

"Your water calculations for collecting from a house are way high."

"And what about growing food or raising animals? Cause any area thats devoid of water is also devoid of economic investment and commerce. Which means you'd have to be pretty self sustaining."

EXACTLY! Even my good-case scenario wasn't enough, was it?

There are places in the world where they would fight over the 2-5 gallons of clean drinking water we use to flush half a cup of urine.

Back when I lived in SoCal, I wondered if ever there was an good earthquake that wiped out the transport of water from the Colorado River, how long it would take to empty the place.

Sue

How Long it would take to Empty the place?I believe you resided in The Val,Am I correct?All of the water for Burbank & Anything West of there in The Valley,Get's it's water from The Northern Aquaduct,of Which is fed Originally from,Owens Lake,Up near Mammoth in The High Sierra's,The LA Basin get's it's water from The Colorado river,Via The LA Aquaduct,San Bernardino,Riverside,Orange Counties get their water from a similar Aquaduct Branched off from The LA one.All of The Aquaduct's Travel along,thru,or aside a Fault or Many Faults/Zones,It Probably wouldn't take much,as long as Most of the Fault Zones, became active All at the same time! I'm All for it,We have Too Many Derilict Visitors,That really don't give a rats keester for The Environment in General!

If the Glen Canyon Dam was to somehow fail i.e. in a earthquake or terrorist attack, then a vast area of the Southwestern United States of America would basically become uninhabitable for about 2o years.

The economic and financial problems it would create would also bankrupt all the western financial institutions i.e. wall street due their exposure to the collapse of property prices in the south western USA where a huge proportion of the 2000-2008 property speculative bubble was generated.

As Mark Twain allegedly said about the west, "Whiskey's for drinking, water's for fighting."

The Santa Barbara desalination plant was actually finished. See here . However, it is kept on stand-by status until there is some emergency or another severe drought. As has been mentioned, it is very expensive to operate and has potential environmental impacts, however, this facility is designed to operate on a long-term basis, if needed. Unlike the LA/Orange County or San Diego metro areas, Santa Barabara doesn't have access to major sources of imported water like from Northern Cal or the Colorado.

Orange County started operating a water reclamation plant a few years ago. Treated waste water is highly processed (further filtration, UV, ozonation, etc.) and then pumped underground to recharge the aquifer. Being so highly processed, I would drink that water, but politically, I don't think most folks would appreciate the water they flush down their toilets making a direct loop back to their kitchen faucets, so the water just goes back to the aquifer.

My city here in Orange County uses recycled water for all municipal landscape irrigation. Our city relies on 100% imported water. My neighbor works for the water utility and he says that local backup supply for our city would last a month if we stopped all irrigation use, so that's fairly reassuring. There are interconnections and agreements with neighboring water districts that have ground water supplies, so even if an earthquake cut us off from the Colorado River or Northern Cal, we'd still be able to limp along for some time.

Thanks, I had no idea the plant had actually been finished. It just seemed to drop off the radar once the rains resumed....