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probes 12th Aug 2015 06:49

Shade balls
 

LA is the first city to use this type of innovation for water quality control. Shade balls are also useful for staving off algae growth and preventing harmful chemical reactions between sunlight and chlorine. In a press release, the city claims shade balls are a “cost-effective way to reduce evaporation each year by nearly 300 million gallons, enough to provide drinking water for 8,100 people for a full year.”
LA Dumps Millions of Plastic Balls in City Reservoir to Fight Drought

http://media2.s-nbcnews.com/j/MSNBC/...eo_170x113.jpg


"This is a blend of how engineering really meets common sense," said LADWP General Manager Marcie Edwards. "We saved a lot of money; we did all the right things."
LA Rolls Out Water-Saving 'Shade Balls' : The Two-Way : NPR

now, would someone explain to my common sense why the balls have to be dark? One would expect light colours work better, the albedo effect and all?

Bushfiva 12th Aug 2015 07:12

A few reasons: the material contributing to the coloring protects the balls themselves from UV. The coloring prevents light from reaching the water surface, stopping light-triggered reactions. The article says this is drought countermeasure, but when LA first started using these balls years ago, they were originally to improve water quality and kill algae. Finally, LA has a lot of experience with this particular ball, gets good pricing, and knows they will last 5 years.

ExXB 12th Aug 2015 08:45


... nearly 300 million gallons, enough to provide drinking water for 8,100 people for a full year.”
That's over 100 gallons per person per day, more than 400l, slightly less in a leap year. My goodness, they must shower a lot.

Sallyann1234 12th Aug 2015 09:29

What happens after five years when the balls have degraded?
It must be quite a job to collect them all up.

SilsoeSid 12th Aug 2015 09:44

Evaporation reduction :confused:

Unless there is a method of preventing any water movement/waves and preventing the balls moving/rotating, the surface area of the water exposed to the air is greater than the surface area of the unballed reservoir itself, thereby creating a greater rate of evaporation.

http://eccllc.us/wp-content/uploads/2014/02/ball.png

Capot 12th Aug 2015 10:13


That's over 100 gallons per person per day, more than 400l, slightly less in a leap year. My goodness, they must shower a lot.
At last! A fellow-spirit who spots absurd "statistics" and pulls out a calculator to see how absurd!

Or maybe is just good at simple mental arithmetic, unlike the clowns who produce such nonsense, and the other clowns who blindly quote it.

Silsoe; excellent point, but I wonder if they are made with a thicker skin at one point to keep them from rolling, and secondly I'm wondering if they would roll constantly in any event so as to always be lifting droplets up for evaporation. I can picture a small amount of movement, but not constant "full circle" rolling. What would make them do that?

Ancient Mariner 12th Aug 2015 10:54

According to this
How Much Water Do Californians Use and What Does 25 Percent Less Look Like? | The Lowdown | KQED News
the figure is actually on the low side. Don't ask.
Per

arcniz 12th Aug 2015 13:34


That's over 100 gallons per person per day, more than 400l, slightly less in a leap year. My goodness, they must shower a lot.
Like near everything else Said or written 'bout California (Hot Oven), the "daily" water estimates have quite a bit of spin wired-in.

When Drought is not on the menu, industry, agriculture, politicians and maybe even the extra 7 or 8 million mostly Mexican and Central-South America phantom residents in the "unregistered" category living in California all favor exaggeration of the State's water-usage to cover over various off-the-books uses and demand components. Agriculture uses a LOT of surface water when it is readily available, and sucks hard on slow-refilling underground aquifers when not.

In "Normal" times California has excess water supply and ample storage for it in reservoirs and snow-pack. Ab-Normal times seem to be coming in 25-year cycles, though. Each dry-spell in the recent series drains the quakey and probably unrepairable-when-broken-through-overuse aquifers a bit more. Plenty room for conservation, but the ag economy will suffer most.... and that is where a lot of the political pull sleeps.. mostly. Some individual farm enterprises control hundreds of square miles of cropland, usually planted in very water-intensive crops that enjoy the summer heat.

Capot 12th Aug 2015 15:10

The original quote specified "drinking water", and went on to imply that Californians drink 100 gallons a day. That was the absurd statistic.

Total water consumption, divided by the population, could easily be 100 gallons per person per day, what with all that plant watering, car washing, swimming pool refilling, wine producing, etc etc, even showering, as I understand Californians do on a weekly basis, or, astonishingly, even more often!

rgbrock1 12th Aug 2015 15:24

To elaborate on total water consumption per person here in the U.S.

Where I live we have a well which supplies our household with water. (Said household is comprised of myself and the Mrs. That's it)

Last year this part of New York State experienced extremely dry conditions bordering on drought. Therefore our well suffered. We had some well people come in and take a look to see what they could do to coax some more water out of the well. Anyway I asked the well guy, just out of curiosity, what the "average" use of water is per person. He replied "100 gallons per day, per person, or so."

To put this in perspective: an "average" shower uses 25 gallons per person. So if you have 2 people taking showers per day, you're already talking about 50 gallons per day just for that. Add in drinking, flushing the toilet, etc. and 100 gallons usage per person per day is not really unreasonable.

FakePilot 12th Aug 2015 15:43

Well, the only thing to do then is measure exact amounts of water used by each person and post a weekly "how do you stack up against your neighbors usage?" With an excess fee applied to everyone when someone exceeds 90% of their actual usage. This is a smart and transparent process.

meadowrun 12th Aug 2015 15:54

Any idea what energy and other resources were expended to make those millions of balls? Carbon tax anyone?

rgbrock1 13th Aug 2015 12:43


Originally Posted by henry_crun (Post 9080814)
My water bill says I use an average of 0.17 cubic metres of water per day. That converts to 45 US gallons personal use for one person.

Usage is drinking, cooking, washing, baths, toilet flush.

You would get a rather larger figure if you include my share of the local infrastructure, such as shops, offices, street cleaning, herbiculture etc, calculated by dividing total city usage by population.

45 US gallons per day, Henry? That's it? :eek::confused:

Henry, is that you?

https://encrypted-tbn3.gstatic.com/i...Kn5MVqWKXDQlYP

ExXB 13th Aug 2015 13:20


Originally Posted by Ancient Mariner (Post 9079723)
According to this
How Much Water Do Californians Use and What Does 25 Percent Less Look Like? | The Lowdown | KQED News
the figure is actually on the low side. Don't ask.
Per

Puts the expression 'having a leak' in a new perspective. 18% lost to leaks inside a house.

Put everyone on a meter and charge for water, as is done here. (We do get a discount on water used outside the home, as it doesn't get treated).

We average (indoors) just over 65l per person per day.

Fox3WheresMyBanana 13th Aug 2015 13:35

As an offshore sailor, I am very conscious of water usage.
I would estimate I use about 45 litres per day (11 US gal) at the moment, with 2 showers per day. These are what is usually known as Navy Showers (turning the water off in the middle), and they are easy to get in the habit of too (and you don't waste soap either). I have short hair, which makes a significant difference; I think ExXB is doing pretty well with 65 litres per day if he has long-haired people in the house

Ancient Mariner 13th Aug 2015 14:03

Here in Norway we are normally "blessed" with more than enough water so the local authorities sees no need for a water meter.In my county the average for 2014 was around 50 liters (13 USG)/person/day.
Per

rgbrock1 13th Aug 2015 14:23

I am totally surprised by the numbers I'm seeing as far as daily water usage is concerned. 45l, 43l etc. Do you people never flush the toilet? :}

And as for you, Fox3, I know what a Navy shower is (aside from not bending over to pick up the bar of soap. :}) We practiced short showers in the US Army as well. IF a shower was even available. Washing one's nasty parts, or parts which turned nasty, out of ones helmet was certainly the norm during field exercises. However, having done that for far too long I refuse to take a shower for anything less than 10 minutes. :ok:

G-CPTN 13th Aug 2015 15:21

When she was a teenager, daughter would 'shower' until the hot water ran out, leaving others in the household annoyed.

Lonewolf_50 13th Aug 2015 15:29


Originally Posted by G-CPTN (Post 9081114)
When she was a teenager, daughter would 'shower' until the hot water ran out, leaving others in the household annoyed.

As a long time fan of the modified navy shower, which takes at home a luxurious two minutes of running warm water, I'd occasionally drop in on my kids who were running the water too damned long and just turn it off (reach in the front, no privacy compromised) and walk out yelling at them about wasting water. Wife not too supportive, and no, I did NOT pull that stunt on her (we ain't that grumpy nor that stupid) It was hard to get them to keep it to five minutes or less. :mad: She's still (my wife) a problem IMO with her overly long showers, so I have to be the first one in and out in the morning. What's weird is that if she's awake she still marvels at how quickly I shower.
"How do you get clean?" she has asked more than once.
"I get in, scrub thoroughly (I often dampen the cloth/scrubber and begin to apply soap to it as the shower water runs to warm up) all over, rinse, wash hair quickly, rinse, and GTFO."

It's a cleaning evolution, not a spa treatment.

An Italian friend of mine once figure out that to get top to bottom clean (mind you, short hair for man/military cut) you need about 3 - 4 liters of warm water and neutral soap. (like Ivory soap).
That's less than a standard one minute Navy shower.
I applied this lesson using a gravity feed camp shower in my back yard a few times, and he was absolutely right. I was clean over all when done. I'd add another two liters of water if I was sure I needed to wash my hair now that it's a bit longer than military crop.


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