Extreme Water Conservation

[matapan]

Alot of people use water daily that could serve a second purpose. Water we use to rinse things off, for example is clean enough to be used for watering plants outdoors.

 

The trouble is, there's no way to distinguish "clean" water from "dirty" water. By "dirty", I mean water that would harm plants.

 

Diverting water to a holding tank for secondary use is fairly straightforward with ISY and Insteon, I would think. There are valves that are electronically controlled for sprinklers that divert water. Next, employing a pressure plate sensor would allow a person to actuate a valve to divert "clean" water to the holding tank when a certain area on the floor was pressed and held. By default, water would go down the city drainage system. A level sensor in the holding tank would prevent the diverter valve from actuating if the water level was high enough in the tank.

 

The same tank could have pipes running from it to the sprinkler controller. Similar logic could be employed, to draw water from the holding tank first to irrigate. When the tank is empty, the valve controlling the water source could then get water from the tap.

 

The water discrimination feature could potentially go automatic too, if there was a way to detect how clean the water flowing though it was in real time.

[aLf]

I have argued this idea in Wisconsin for years. THe water that is used for showering is very clean, grey in fact. Many states, and I believe Michigan is one, allow the diversion of "grey' water to a seperate holding tank which is designed to remove any "solid" then return the water for watering plants, lawns, etc. Unfortunately our DNR does not allow it. I have holding tanks for my house and I'm sure that 75% of the water could be re-used. Instead, it is dumped twice a year on a farm field! Go figure.

 

As far as determining the difference between dirty and clean, it is actually very easy. The soaps that are OK for plants are not that bad for showering, etc. Obviously the toity and kitchen sink have to be hauled off.

 

aLf

[dronning]

30% or more of water usage goes down the toilet. Why not use the grey water for the flush. You could use a diverter to pull from either the grey tank or the main when the tank gets empty. I am catching rain water from the street side of the house that would normally go down the storm sewer to water my yard and flush the toilets. Cuts the water bill by 70%. Works great in the summer, the grey water idea may be a good solution for winter and for dry summers like this one.

[apostolakisl]

Are you sure you want your toilets to have soapy discharge water from your shower or washing machine in them? You would build up a nasty "ring around the toilet". Also you would need to run brand new water lines to your toilet and put pumps and pressure holding tank like you would use on a well.

[dronning]

Are you sure you want your toilets to have soapy discharge water from your shower or washing machine in them? You would build up a nasty "ring around the toilet". Also you would need to run brand new water lines to your toilet and put pumps and pressure holding tank like you would use on a well.

 

I don't think I'd use the washing machine even though we have a low water/detergent use He3

 

grey water flush:

There are several commercial systems out there that do the proper filtering, like the Aqus vanity based system or the BRAC whole house system, so this can be done.

 

About 35% of water usage is from shower/bath & 30% is toilet flush so using shower & bath water with proper treatment should work.

 

We currently use rain water from our cistern system for both toilet flush and sprinklers. Not at all difficult and we are investigating what it would take, and what the issues might be, to use the cistern/rain water for showers then save the grey water for the flush.

 

Expensive yes you'd have to live there in the house a long time to re-coupe the costs. I have also converted most of my house to LED lights at $30-50 a pop I don't think they will give me pay back either.

 

I guess I am saying it's not about ROI for me.

 

I updated my whole house to PEX last year during a remodel. The cool thing about that is I have home runs to everything so I can "MIX" it up at the distribution manifolds.

 

Dave

[apostolakisl]

Lots of people are using rain water for all of their household use. I live in Austin Texas and it is very common here out in the hill country where city water isn't an option. You need to put in a huge cistern because it can go a long time without raining. A typical family of four would use about 4,000 gal per month with low water consumption everything. Most people who do this put in 15,000 gal holding tanks. Still at times they have to pay for delivered water or use well water to fill the system. There are companies that do the whole thing. You have a series of filters before the rainwater goes into the holding tank and then final filters before it goes into the house, including a uv light filter. The water quality is excellent, no minerals at all. Also no flouride though. It is very expensive and requires space to put a very large holding tank. Also, the tank needs to be protected from light or it will grow algae on the inside. Plus you need a relatively large roof. If your roof covers 5000sf of foundation, then you will get 3125 gal/inch of rain assuming you catch it all. Of course you don't get it all. Some of the rain evaporates off of a hot roof and some of it just goes to making the roof wet which evaporates after it stops raining.

 

It is simpler if it rains often where you live because you can have a smaller tank. But if it rains a lot where you are, then there probably isn't much point in conserving water. My parents live in Harbor Springs Mi where water literally just comes shooting out of the ground all on its own. The water company doesn't even bother metering the water, it's just a flat monthly rate. The real reason they even charge is to take care of treating the sewage side.