The Tucson gray water myth.

While researching green ideas for my house, Graywater plumbing was among the top of my list. 

Greywater, sometimes called graywater, or sullage, is considered non-industrial  waste water generated from domestic processes such as clothes washing, showering/bathing.  Greywater comprises of 50-80%  of residential waste water.  Greywater is distinct from blackwater  in the amount of and composition of it’s chemical and biological contaminants.  For example, water discharge from the dishwasher or kitchen sinks has an increased amount of food  and contaminants and is considered dark or blackwater.

When I was ready to build my house, I phoned five different plumbing companies, asking if they were familiar with grey water systems or simple grey water plumbing.  The first 4 companies gave me a song and dance about special codes by the city, all of the cost, blah blah blah.  The last company I called was actually EXCITED about greywater plumbing.  The owner of the plumbing company told me he would draw it up and we talked at length about the fact that very few people actually think about it.  He showed me a pamphlet containing the county’s ” grey water use requirements” which is listed below:  ( These requirements cover most of Southern Arizona)  You can also click on this link and view it as well: www.azdeq.gov

1.  Avoid human contact with gray water.

2.  You may use gray water for household gardening, composting, and lawn and landscape irrigation, but it should not run off of your property.

3.  Do not surface irrigate any plants that produce food, except for citrus or nut trees.

4.  Use only flood or drip irrigation to water lawns and landscaping. Spraying gray water is prohibited.

5.  It cannot drain into a wash or drainage way.

6.  Gray water may only be used in locations where groundwater is at least 5 feet below the surface.  (Funny!)

7.  Label gray water pipes under pressure if confusion between gray water and drinking water pipes is possible

8.  Cover, seal and secure storage tanks to restrict access by small rodents and to control disease carrying insects.

9.  Hazardous chemicals such as anti-freeze, mothballs, and solvents cannot be in gray water. Do not include wash water from greasy or oily rags in your gray water

10.  Gray water from washing diapers or other infectious garments must be discharged to a residential sewer or other waste water facility, or the water can be disinfected prior to it’s use.

11.Surface accumulation must be kept to a minimum.

12.  Should a back-up occur, gray water must be disposed into your normal waste water drain system.

13.  If you have a septic or other on-site waste water disposal system, your gray water use does not change that system’s design requirements.

  Now, I elected to use a “passive” system, which does not require pumps, filtration systems or the likes.  I have two zones where one half of the house discharges water to one side of the yard along with the washing machine, an the master bathroom and powder room discharges on the opposite side.  I do have a valve that will allow me to direct the gray water into my septic tank if, for instance I clean the shower with a partially caustic chemical.  There are no pumps, just pipes that I direct to the plants in my yard.  I’m sure I will eventually add a somewhat unsophisticated pump and filtration device to irrigate my plants, and I am working on a design for that as I write.  As far as the septic system we have for our house, we still were required to have the same size tank for the house as if we were not using gray water. 

In reading over the ADEQ reclaimed water pamphlet,  there is a small paragraph on the pamphlet that says, ” Residents must adhere to the guidelines for reclaimed water type 1 general permit. A type 1 general permit requires NO formal notification to the department, NO review or design approval, and NO public notice, reporting or renewal.

Now, lets talk about houses that are pre-existing.  Your best bet for a grey water conversion would be with an older home that has a raised foundation.  The plumbing pipes are accessible ( for the most part ) and can be converted.  The other 90 % of the homes have slabs, and is cost prohibitive to retrofit to gray water.  The only homes I’ve seen have been where the laundry is outside in a carport closet and is the only grey water used, and can be done much more easily.

So far my plants love it, my water bill is lower than most, and I feel like I’m doing something to help the drought!

Water Water Everywhere…

Here in Tucson,  we have been in drought conditions for several years now, and yet we do nothing to rectify or lessen the effects!  Yes, several people in town will collect rain water off their roof, or use grey water, but as a home inspector, I see a great many houses and the majority ignore the fact that we live in the desert and have limited water.   Seriously, how much water do you think it takes to keep grass alive in a yard with 100 degree temperatures for weeks on end? 

As a home inspector, I find simple things that can be done to save water.  Replace or repair the inner workings of your toilet if it free flows.  Better yet, replace any old toilets  (4-5 gallons per flush) with the new ones that have a 1.6 gallon flush.  Fixing a leaking faucet can save up to 20 gallons of water per day! Other water saving ideas would be to replace shower heads with water saving heads, and believe me, you won’t know the difference in pressure!

Only run your washing machine or dishwasher when you have a full load. For that matter, hand washing your dishes saves hundreds of gallons of water.

There are retro-fit hot water recirculators that will give you hot water in seconds, saving all that water while we wait for the water to warm up.  Costs run about $200.

If you don’t want to spend the money on a recirculator, while waiting for the shower to warm up, capture the cold shower water in a large bucket so that you can use it for watering your plants later. You can save 200 to 300 gallons of water per month!

plant low water use plants for your landscaping, also called Xeriscaping or xeroscaping.

Check your irrigation system for leaks, and make sure of what you are watering.  Don’t continue to water dead plants or plants that you have removed. Check your hose bibs, faucets, etc., for leaks and fix them.  “slay the dragon” when it is small, instead of waiting! 

Other interesting ideas are rain water collection ( there are some things to worry about with this though, like mosquitoes, and the dreaded Home Owners Association! ) using grey water ( the water from your laundry, bathroom sinks and showers) to water your plants.  This is impractical to retrofit an existing home on a slab, however if you have a raised foundation, or a manufactured home, it would be relatively simple.)

You can find more info on the web at www.monolake.org/socalwater/wctips.htm or at the blog roll for Tucson City Water.

There are many other sites as well, but this seemed the most comprehensive.  

Save water!  Save money! A little responsibility goes a long way!