Largest Desalination Plant in the Hemisphere to Supply 7% of San Diego's Water

in environment on 2014-09-22 21:08 (#2SSJ)

At 70 percent complete, and slated to be open and operating November of 2015, the Carlsbad Desalination Project is predicted to be, at 50-million gallons per day, the largest and most energy-efficient seawater desalination plant in the Western Hemisphere. And it will supply enough water to meet about 7 percent of San Diego county's water needs.

The water authority has pledged to buy the desalinated water at $2,014 to $2,257 per acre-foot. About twice the cost of traditional water supplies, but about half that of desalination plants just 10 years ago. An acre-foot is enough to supply two homes for a year. During the first full year of production - in 2016 - the desalinated water will add about $5.14 per month to the typical household's water bill, according to the water authority.

"This source, since it's not dependent on rainfall and snow melt, is the (region's) first drought-proof source of water."

But they're not going all-in with desalination. San Diego city's plan to purify wastewater to drinking-water standards is the next major item on their agenda. The city envisions constructing a water-purification plant that can generate 83 million gallons of drinking water per day by 2035. The purification plant could also help eliminate the need for $1.8 billion in overdue upgrades to the Point Loma Wastewater Treatment Plant by reducing the amount of wastewater that must be piped to sea.

Stillsuits (Score: 1, Funny)

by Anonymous Coward on 2014-09-22 21:45 (#2SSM)

Let's just skip to the end-game why don't we.

How much water / house? (Score: 1)

by Anonymous Coward on 2014-09-22 23:54 (#2SSR)

... An acre-foot is enough to supply two homes for a year.

Half an acre-foot is 162,926 gallons (per a couple of different online conversion programs). I'm in the Great Lakes area where we don't pay much for water and our house (two people) uses about 30,000 gallons/year. Even when we were watering a few new trees we only got to 40,000 gallons/year. We don't do anything special to conserve except the toilets are the low flush type and faucets/sinks have typical 2 gallons/minute aerators (flow restrictors).

What are they doing in San Diego to use 5x the water we use here?

Re: How much water / house? (Score: 0)

by Anonymous Coward on 2014-09-23 00:29 (#2SSV)

Just wild guesses but:

2 people is below average

4-5 person households poop, pee, drink, andBATHE 4-5 times more than 1-2 person households

California is hotter than your locale

They are using conservative guesses

They are using very rough numbers

Reporters are stupid

Tiny hydroelectric household dams

Re: How much water / house? (Score: 1)

by evilviper@pipedot.org on 2014-09-23 10:14 (#2SSX)

our house (two people) uses about 30,000 gallons/year. Even when we were watering a few new trees we only got to 40,000 gallons/year

Two-people is a ridiculously small household, and you are in an area where you don't have to water your yard at all, where most of the Southwest you'd have nothing but dirt unless you water the whole thing twice a week.

Re: How much water / house? (Score: 1, Informative)

by Anonymous Coward on 2014-09-23 02:46 (#2ST1)

Big difference between "water use" (measured by the house water meter) and "water footprint" (all the water used to produce goods consumed by a person). From the Wiki source, footnote [3] http://web.archive.org/web/20081004003759/http://www.ibisworld.com/pressrelease/pressrelease.aspx?prid=125

IBISWorld estimates that the typical single family home consumes 69.3 gallons of water per day.

69.3 x 365 = ~25,300 gallons/year. So OP is correct that 30,000 gal/year is reasonable in Great Lakes area with no special conservation efforts, and probably some limited watering during the summer if there is a temporary dry spell.

The San Diego number for a house (seems most likely based on actual metered usage) is very high, must be watering outside all the time? Anyone from the southwest care to share their water consumption and water bill?

Re: How much water / house? (Score: 1)

by evilviper@pipedot.org on 2014-09-23 05:50 (#2STA)

Big difference between "water use" (measured by the house water meter) and "water footprint"

Good point, I wasn't paying attention on that one...

IBISWorld estimates that the typical single family home consumes 69.3 gallons of water per day.

That's not even close to what the EPA says:

"The average American family of four uses 400 gallons of water per day." -- http://www.epa.gov/watersense/pubs/indoor.html

400 * 365.25 = 146,100 gallons

That puts San Diego pretty close to average.

The USGS says almost the same, at 80-100 gallons per person, per day.

http://water.usgs.gov/edu/qa-home-percapita.html

Re: How much water / house? (Score: 1)

by bryan@pipedot.org on 2014-09-23 07:20 (#2STE)

On my monthly water bill, the local utility lists the following:

Your water use was 748 gallons.¹
Your neighborhood average water use was 7,998 gallons.
SAWS residential average water use was 10,085 gallons.

I have no idea how some people use so much water.

¹One digit on my water meter equals 748 gallons. For some months of the year, my usage is low enough to make the meter read the same as the previous month (meaning my usage is actually a bit less than 748 gallons/month)

Re: How much water / house? (Score: 2, Funny)

by zafiro17@pipedot.org on 2014-09-23 09:16 (#2STJ)

Swimming pools and automatic lawn-watering sprinkler systems ought to be the biggest culprit, I'd say, although having kids also raises your water bill in a noticeable way.

I personally lower mine by bathing infrequently :) Smells so ... "economical."

Re: How much water / house? (Score: 1)

by evilviper@pipedot.org on 2014-09-24 12:24 (#2STR)

Your water use was 748 gallons.1
Your neighborhood average water use was 7,998 gallons.

That's an incredibly low figure. I'd guess you eat out all the time, don't wash your own car, have no plants, don't do laundry, take very short showers days apart, and more. Or otherwise are away from home a great deal of the time. While that behavior may reduce your home water bill, you're still using lots of water, and in a way that's far more expensive than just using water at home.

With the standard 2.5 GPM shower head, 750 gallons is just 5 hours of running the shower per month, total. Some people take 5-minute showers, or skip quite a few days in-between, but most don't, and the average would also go through the roof in a household of several people, so that's not really a practical level of water usage to expect of people, except in cases of extreme rationing.

And showers aren't the biggest water users... Toilets consume more water, so you need to cut your showering time down to 1/3rd of that to fit the numbers, still. Throw in some dish washing, outdoor plant watering, and you get up to those big "average" numbers quickly.

Re: How much water / house? (Score: 1, Funny)

by Anonymous Coward on 2014-09-23 12:56 (#2STX)

Shhh. Bryan's last name is "Begley, Jr."