Arrested Development - Ex-Pats Mexico

I wanted to make a grey water (washer, shower, sink) drain field separate from the septic but can't find the type of drain field tubing used up north. I was going to dig a trench with gravel, pipe and more gravel. About one meter down we hit sand so drainage should be good. Without a porous pipe I've run out of ideas short of drilling holes in white drainage pipe. Most of the stuff on the Internet is about re-cycling grey water and I don't want to re-use it .... and I've heard grey water collection can be nasty

I used gray water to feed a hedge row when I lived in California. Worked very well.

At first, I included the kitchen sink waste water, but that did not work out well -- too many food particles that drew flies.

Why would you want to divert the gray water? You need it to help dissolve and flush the waste in the field drain.

Its not only the pipe you need, but also a sort of landscape fabric so that surface water can flow through without clogging up the field or the pipe. I guess the theory is that it is eventually easier to dig up and replace the fabric than the whole field. I have a chapter in a book somewhere - I think if you searched "french drains" you might get a better idea. My application is for a motorhome I would like to bring to Mexico. Black water is from a composting toilet, nothing to worry about there. Grey water cannot accumulate long without getting stinky. A composting toilet for more than six people full time would be a fairly big expense. The newish solar powered (w battery backup) fans take care of any smells.

There shouldn't be any waste to flush in a septic/drainage field unless the holding/fermentation tank is full of undigestables - and therefore needs pumping. The only thing the sewage tank should output is fairly clear but smelly water.

The problem in Mexico is that most lots don't have the room for a septic and drain field that is 'legal' up north. We have 2 lots so have some space but for 2 houses and many people. Everything I've read on the Internet says that you can keep water flow thru a septic minimal with no problem and lots of detergent can stop the bacterial action. I would keep one bathroom and the kitchen on the septic and 2 baths and laundry would be a separate grey water drain. Complicated but the number of showers and washes per day is a major issue with this family

Have you thought of using the Wetlands concept for dealing with the outflow?



CEA has some information on it, I'm not sure why they don't have actual plans for building them. Look here and here for some info. These work well with black water even but very well for gray water. You can plant fruit trees like banana in them and the fruit is safe to eat. Bananas in particular do well because of their high water needs.

Here is a septic system that is being used when space is a problem, it uses no leach bed. The one that is used in Ohio has a motor and paddle that aerates and nothing but clean water comes out the end so they say. http://www.inspect-ny.com/septic/altaerobic.htm

I guess I could talk to these guys (AproSanidad Melaque, A.C.) for ideas. This project is a municiple one and they have been installing these bathrooms around the lagoon where it is difficult to bring the house into the sewer system or there is no sewer. They separate grey water from the toilet. Urine and dry material is collected and processed at the local treatment plant



A newer foto

The septic is not a problem and we have to anticipate having sewer in the street someday. Some houses around here have septics under the house (cisterns as well) and the out flow goes into the street

It looks like the gray water is going into a wetlands just like the ones in the links I posted. They work exceptionally well, no smell. There's a very nice tourist restaurant in Akumal where the outdoor dining area is right next to a planted wetlands and the diners never know it. There are orange trees, bananas, and flowers growing in it. It's a great way to treat water and a nice landscaping tool as well.