Why don't houses have TWO grades of water (drinking and sprinkling)?

Question

I'm always puzzled by this. We know gasoline is precious and limited, whereas water is semi-precious and reuseable. Yet it matters to save water or else in the future we may have shortages due to population growth, or global warming.

So if water is sort-of-precious and must be saved, why are home and residential distribution systems so that we drink the same water as we use to water the garden or to take a bath (grey water)? Shouldn't houses have TWO grades of water ie two parallel plumbing systems?
Adding the 'grey pipe' on older houses seems kind of late to do cost-effectively now, but can we still do this on newer houses? Would it be worth? Imagine how cheaper it is for a plant to produce grey water, very little filtering needed.
Am I the first one to think about this?...

Answer 1

I see where you are heading with this, but the trouble arises with the delivery system. You'd need to create two new sets of water delivery systems on a municipal and household level. Which doubles operation costs; requires twice as much construction materials; and obviously increases maintenance costs.

I'm not sure this is the best approach overall in promoting water conservation at home.

Couple of interesting statistics: toilets account for 26% of a households annual water usage; leaks consume nearly 14% of a homes yearly water usage!

The first thing you can do to reduce your water consumption is to make sure your system is leak free. This is fairly easy to do and often doesn't cost a great deal.

Another trick (many homes in Canada have done this) is to fill a two liter plastic bottle with gravel and water. Then put this in your toilet tank -- this basically (via displacement) reduces the volume of water used with each flush.

The second link below offers 49 tips on how to best save water at home. There are some really cool ideas!

Answer 2

I think the answer to you question, Why?, is that populations grew from small to large everywhere. When people first settled an area there was plenty of water(otherwise they wouldn't settle). This may have occurred at different times in history at different places, but the process was usually the same.

In areas where water was harder to come by, collecting rainwater was the priority, or wells were sunk. But still the amount of grey water was small and where precious it would be use on the crops. (in undeveloped parts of the world today people put all their waste in their crops, they don't even have pit toilets) Also remember daily bathing and wearing of clean clothes is a modern practice, and is not even practiced in the developed world(look up origin of perfume) so water use was much less per person than it is today.

So any attempt to utilize grey water where fresh water becomes scarce involves adaption to existing infastructure. I know there are communities that have looked at the issue and perhaps some have actually done something but most of what I have heard is relaterd to cleaning the water so it may be added to lakes and streams without polluting them.

In the 60's many of the "back to the landers" were very green and built many green water systems. It could have involved rainwater collection and storage but also included grey water stystems. In these cases the grey water was all used water except sewage. The water was plumbed and piped to their gardens. As far as converting your home or homestead, the cost is probably the biggest factor, but also most homes could not use all the grey water they generate.

I hope this helps.

Answer 3

For the most part, the reason is because of the cost. While it may be expensive today, imagine the cost of replacing all the pipes twice 50 years from now instead of only 1 line. Where I live, it's a big issue with the old water lines bursting several times a year but they don't have the money to replace them.

However, some towns do have two different lines for drinking and sprinkling but not in the way you think. Changing a drinking water facility to produce drinking water and 'grey' water doesn't deal with the problem of water usage and conservation. Those towns are usually in arid places where water is much more difficult to obtain so they use the effluent from the waste water treatment facility to water lawns and golf courses.

Answer 4

You wouldnt want to take a bath in grey water lol. I think the issue here for me is why are you watering the garden? Why do you need to 'sprinkle'?

We need to relook at how we design our environments in my opinion. Everyone should be on a water meter, so they are charged for the water they use. Then any leaks/breaks in the system would be quickly repaired because it would be costing somebody directly - either the water user or the supplier. Paying for what you use is the most socially just way.

Secondly rain water can easily be harvested, collected and stored in water butts, this is the simpliest method. This can water can then be used outside.

The biggest issue for me in the reason why people need to 'sprinkle' in the first place. DESIGN the environment to fit the climatic conditions. Plant trees to collect then store water so they can release it when needed. Plant trees for shade, windbreak, to produce fruit, nuts, timber, fuel. Using natural materials such as large boulders and shady areas another microclimate can be produced by the thermal gradient between these two zones creating a cooling breeze. Large bodies of water such as reservoirs and lakes also help to emeliorate the local climate. If everyone with a garden planted climate appropriate plants, had even a small pond and planted a few trees then the land would not become overilluminated and would not need 'sprinkling' ever.

Answer 5

To be honest, I have often wondered why houses near the coast (a significant percentage in many Countries / states) do not have three grades:-

Drinking / showering / bathing etc
Grey water - from above outlets for garden
Sea water for flushing loo

I'm afraid I think you need to use drinking quality water for bathing - not only for youngsters who might drink the bathwater but also because the idea of stepping out of the shower and needing to remember to now wash hands and face in CLEAN water before handling food etc seems a bit too much to ask.

Just as an aside, I think you are using the term "grey water" in a different way to the norm.

Usually grey water refers to water that has already been used by the household - eg: for bathing / showering and is stored for use on gardens. This is very common in parts of Spain / Canary Islands.

In short, I think with a minor tweak, your idea is excellent.

Mark

Answer 6

Newer homes in some communities do this, but to retrofit a 2nd set of pipes is cost prohibitive, as you say. Reclaimed or recycled water is being used in areas like Irvine, California. Forward-leading water agencies in places like the arid southwest are going this route by necessity.

Great minds think alike, I guess.

Answer 7

In Australia the government is making new development recycle the water. I don't know the exact details of whether the grey water pumped back to houses for reuse but it is definitely being used in industry and councils for non potable purposes.

Answer 8

It is just cheaper to make the water treatment plant big enough to make all water delivered in the one set of pipes clean enough to drink. In other words, I don't think the treatment plant is the biggest cost. It is the pipes that are the big cost.

Answer 9

You wouldn't want to pay the taxes that would be necessary for a city to run two sets of water lines throughout the city. Neither did the people who were alive when our cities were built.

Answer 10

No, the amount of water in our world will stay the same, because the water cannot leave our earth therefore we will always have enough water. But , scientists in Europe are trying to convert salt water into freshwater that is drinkable by heating it up then sprinkling it back down. when sprinkled the salt will be seprated by the water and you have freshwater. They are already using this in some parts of Canada.