Replies

1. 
   hotsawdust | May 19, 1999 05:58pm | #1

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   A great idea but because of behind-the-times planning and fear of litigation by municipalities its illegal in most places. Only exceptions I think are in very water-scarce areas like the SW: I think in some places you are able to use grey water for watering lawns (?). I looked into it here but grey water and black water are considered the same, two septic tanks=two leach fields.

   Good luck to you though....

1. 
   Steve_Kasower | May 20, 1999 01:22am | #2

   *RustyC,There is an organization in California who list some documents on Gray Water Systems on their webpage at http://watereuse.org/Pages/orderpubs.htmlI also believe that California has adopted a Gray Water System appendix to the Uniform Plumbing Code, but I am not familiar with the letter of that appendix. I suggest that you followhttp://watereuse.org pages over to the California Department of Health Services pages and see if you can aquire that appendix from them.

2. 
   Guest_ | May 20, 1999 04:20am | #3

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   Rusty

   I've designed and installed several grey water systems for seasonal dwellings that don't have enough property for a typical septic system. We don't use them for
   i recycling,
   however. There is still considerable bacteria in grey water which makes recycling problematic.

   The systems that I've built use a 45 gallon plastic drum, kerfed or drilled with many openings to allow for drainage, buried and surrounded with limestone gravel, and then sand. The drum typically takes shower/bath, lav., and clothes washing water. Kitchen sink (because of inevitable grease) & toilet drain into seperate holding tanks that are pumped out periodically.

   I've retrofitted several plumbing systems to accomodate grey water and its a fairly easy task. Depending upon use (especially clothes washing- extra soap & lint) the entire drainage system might need to be cleaned/replaced in 10-15 years. A fairly reasonable tradeoff when compared to monthly holding tank pumping fees.

1. 
   Guest_ | May 20, 1999 11:15am | #4

   *Rusty,Some more light reading for you at this siteRegardsMark

1. 
   Guest_ | May 20, 1999 07:45pm | #5

   *Grey water systems that use recycled grey water instead of some clean water, can eliminate some consumption. But, a grey water system will not reduce septic system loads. A septic system must be designed for the entire projected household water consumption plus a substantial cushion, eliminating grey water should not be used to reduce the design capacity. It has been shown that the effectiveness of a septic system is not dependent of the volume of water introduced but to the volume of waste that must be digested. Grey water contains very little digestable waste and will simply add volume to the amount of effluent. If the system is so marginal that elimination of grey water makes a difference in whether or not it can handle the effluent then it is not a properly functioning system. In order to be effective at saving water, grey water systems must make use of the grey water. Simply routing grey water around the sepic tank to another means of surface or subsurface disposal will do no good. Introducing unfiltered grey water into any presurized plumbing system that contains valves or pumps is to invite potential problems. Probably the only truely cost effective greywater systems are for irrigation.

1. 
   Guest_ | May 21, 1999 01:16pm | #6

   *Following on Mike's thoughts: A co-worker had studied the contirbutions of households with and without garbge disposals on wastewater treatment costs at the city sewer plant. (Because an Austrailian city wanted to tax people accordingly). The answer: Houses with disposals put 5 times more BOD (biological oxygen demand) down the drain than those houses without. Makes sense: Although chunks go down the toilets, that stuff has already been eaten once. Whereas kitchen scraps and plate scrappings are essentially brand-new food to the bacteria. Rusty: The sandfilter you mention will knock down a lot of the BOD. The sand creates a lot of surface area on which a bacterial film develops. -David

1. 
   Guest_ | May 21, 1999 04:48pm | #7

   *The surcharge is not entirely fair because a higher influent BOD actually makes the sewer plant run better. Unless the discharge permit has "dated" discharge limits the plant should operate fine.-Rob

2. 
   Guest_ | May 21, 1999 09:11pm | #9

   *If I recall correctly, it has been only recently that NYC has allowed disposers at all. I think they are great for getting rid of what accidently falls in them. I don't put anything down them that can't be rinsed in. It beats emptying a basket strainer. The stuff that goes down the toilet i.e. sh*t, is what makes the septic system work. This is why additives are a waste of money. Even if you sterilized your tank, say with a gallon of bleach, it would recover within a day of the first sh*t into it.

3. 
   Rusty_C | May 21, 1999 09:11pm | #8

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   Have any of you ever seen/installed a gray water system in conjunction with a septic system? Saw this somewhere -- drains from the tubs, showers, and washing machine are run seperate from the toilets. The gray water is run through a sand filter, into a holding tank, and then used to charge/flush the toilets. Cuts water consumption and septic load in half. Where can I get details/plans for something like this? Is it legal in most locals? And, no, just running the gray water out on the ground will not do where I am.