Build a Washing Machine Greywater Surge Tank

After the shower, the next best source for greywater is the washing machine. Constructing what is called a surge tank with a fifty gallon plastic drum is the simplest way to reuse your washing machine waste water. Perfectly good water that would ordinarily just go down the sewer will instead water your plants after first spending a short time in the fifty gallon drum.

Temporarily draining your washing machine into a fifty gallon drum has two advantages. First, it allows hot water to cool and secondly it prevents siphoning mishaps and washing machine pump burnouts that can happen if you try to move the water directly to your garden through a pipe. Here’s how to create a surge tank:

1. Get ahold of a fifty gallon plastic drum. Most big cities, Los Angeles included, have businesses that resell used drums. Make sure that you get a food quality drum and not something that held toxic materials. The best kind of drum for this purpose is one that has a lid, both so that you can clean it out periodically, and to make it easier to fit the hose connection at the bottom.

2. Drill a 1 inch hole in the side of the tank at the bottom.

3. You will need to improvise what is called a “bulkhead” fitting in order to hook up the tank to a regular garden hose. Instructions for doing this can be found here. Seal the fitting with silicon. Connect this fitting with a standard garden hose and use a ball valve if you want to be able to hold the water in the tank temporarily. Remember that greywater quickly turns into black water if allowed to sit around for more than 24 hours, so use this water quickly.

4. Direct your washing machine’s drain hose into the tank. The hose must first go above the top of the machine before going down into the tank in order to prevent the machine from draining accidentally. Also, don’t make this connection airtight–the washing machine needs an air gap, normally provided by the loose connection to the standpipe to prevent waste water from siphoning back into the machine.

5. For a deluxe installation, use a three way valve so that waste water can be easily shifted back to the sewer line should the need arise.

6. Place the tank on bricks to increase water pressure.

7. Remember not to use washing machine waste water if you are washing diapers.

As always, for more detailed information on how to do this get Art Ludwig’s excellent book Create an Oasis with Greywater.

DIY Outdoor Shower

Photo by the MacAllen Brothers

Showers are overrated. The first step in considering whether to build an outdoor solar heated shower is to take a step back and consider boring old conservation. Shower less and make sure that your domicile is equipped with a low-flow shower head. Not only will you be saving water and burning less fossil fuels to heat that water, but your body odor will soon separate your real friends from superficial hangers-on.

But we urban homesteaders don’t need to be stinky since it’s possible and easy to build an outdoor solar shower. There are two reasons this makes sense, particularly in a place with as warm a climate as LA. First of all, you can direct the water straight into the garden and in so doing irrigate some plants and keep that water from uselessly running down the sewer line. Secondly, placing the shower outdoors makes rigging up a solar heating system somewhat easier and less expensive. Of course, the solar heating part isn’t completely necessary, and it’s possible to run the hot water line out into the garden, especially since you don’t need to worry about the pipes freezing here in sunny LA. One thing to remember–however you rig the shower, make sure to keep the water directed away from your foundation.

Let’s say you’re ready to build your own solar heated shower and you’ve overcome your fear of being nude under the all seeing eye of LA’s police and media helicopters, what we like to call our “ghetto birds”. We’ll start with the most simple solar shower designs and proceeding to the deluxe models.

First off is the camping shower in a bag concept. The principle is simple–you fill a black bag with water, leave it out in the sun, and hang it somewhere for your very brief shower. We’ve not tried one of these things, but we suspect that the result would be less than luxurious, and after all, part of the reason to bathe is the relaxation it offers. But, for the mortifier of the flesh out there, one of these things might just suffice. They are certainly cheap at around $18. If you are really cheap, you can improvise the solar bag shower by filling a car inner tube with water and leaving it out in the sun.

A variation on the bag shower can be constructed out of inexpensive black ABS pipe. Basically you construct a square out of pipe, put water in it and let the sun heat it up for a few hours. Your shower lasts as long as the amount of water contained in the ABS pipe. Plans can be found here. ABS is easy to work with, and this particular design could be scaled up for longer showers. SurviveLA will run some experiments with this design and let you know about the results.

In terms of other do it yourself options several folks have experimented with simply coiling up a length of black garden hose on the roof. A nice example can be found here, and also at the Path to Freedom. The problem with this approach is that when the water is out of the hose, that’s the end of your hot shower.

A more advanced DIY solar shower that resembles commercially available (and expensive) solar water heaters can be made by constructing a glass covered collector box containing a manifold of copper pipes that feed into a used water heater. Hot water contained in the copper pipes in the collector box rises up into the water heater that is kept above the level of the collector. Hot water rises just like hot air and the cold water from the tank sinks back into the collector thus forming a circulation loop–this phenomenon is known as thermosiphoning. Some plumbing skills, are necessary, but it’s relatively easy to learn how to sweat copper pipe. We’ve used a system like this provided by the National Park Service on SurviveLA’s trip to Santa Rosa Island. The nice thing about storing the water in a tank is that you can take a shower well after the sun goes down. Plans for this project can be found on the Mother Earth News website.

Whatever approach you try, the key thing is to keep the costs down and to use as many found materials as possible. The water and gas savings per year are minimal, so in our opinion it does not make sense to buy expensive commercial outdoor showers (like the one made by Hammacher Schlemmer) when you can make something yourself.

An excellent roundup of DIY solar projects including water heating can be found at Build It Solar.

Showers to Flowers

Here’s the truth, I’m lazy. So when it comes to the aforementioned greywater strategies such as bucket flushing and siphoning, while we might try them for a while we’ll most likely quickly tire of all the repetitive effort barring some apocalyptic water shortage. SurviveLA agrees with Art Ludwig, author of Create an Oasis with Greywater that the best greywater systems are the simplest, and involve the least amount of effort and maintenance.

One of the easiest and more permanent greywater solutions is simply rerouting your shower straight out a pipe and into the garden. Here’s how to do it:

1. Confirm that your shower is higher than the point you are watering. The minimum fall for waste pipes is 1/4 inch per foot — any less and you’ll risk a backup.

2. Cut the waste line from your shower, making sure that you are cutting the pipe before the point it meets up with anything coming out of the toilet. Remember you don’t want blackwater in your garden. If possible (i.e. if easily accessible via a trap door or some other configuration), install a three way diverter valve like the one pictured above, so that water can be shifted back to the sewer, if needed, such as during a long rainy period. Keeping the minimum fall rate in mind, run the pipe out to where you want to water.

3. Choose plants whose watering requirements match the amount of water coming out of your shower. To do this you’ll need to estimate how many showers and how much water you use per shower. Odds are it will be water hungry plants such as banana trees.

4. Create a mulch basin around the plants you are watering. The mulch could be gravel, wood chips or leaves. The mulch basin has multiple purposes – it slows the flow of greywater, preventing runoff and it stops greywater from forming stinky pools. Mulch also prevents contact by kids and pets and helps keep down the mosquito population.

5. Some precautions – put a screen over the end of the pipe to prevent rats and other critters from climbing up the pipe and surprising you in the shower. Keep the destination of the pipe well away from your house’s foundation, especially if you have clay soil.

Siphon Your Bathwater

So it’s back to greywater today with a tip on siphoning your bathtub water. The concept goes like this. When you take a shower keep the plug in. Yes it’s a bit gross at first, but you get used to it. When you are finished, submerge a length of tubing in the bath water. Hold your finger over one end and pass it to an accomplice waiting outside in the garden. As long as your bathtub is higher than the part of your garden being watered, you will have created a siphon and the water will drain out of the tub.

Now if this sounds like a pain in the ass, or if you have no accomplices there is (or perhaps was as the website does not seem to be working) a siphon device on the market for just this purpose. Called the “Ban Beater” this siphon pump was being sold in the UK as a result of the draught that struck south-east England this year. However, this greywater siphoning tool is on the expensive side and it’s hard to justify spending a lot of money just to save a few cents worth of water, especially when the siphon devices themselves are produced with plastic and other petrochemical products. Devices like these suddenly become popular when governments institute water rationing as did the British earlier this year. There are less expensive siphoning devices available in hardware and auto parts stores made for siphoning gas, but SuviveLA has not tested them yet.

If siphoning is too much effort for ya, it’s time to move on to more permanent solutions involving rerouting your plumbing that we’ll get into in subsequent posts.

Greywater Precautions

Before we continue our greywater series, we have a few precautions to lay down. The dangers of greywater have been exaggerated in the past and it’s important to remember that nobody in the US has ever gotten sick from exposure to greywater. The plumbing codes in this country are overly cautious in their restrictions on greywater use, as the Man, quite simply, wants you to throw perfectly good water down the sewer. On the other hand, a lot of hippie types have been a little too loose with greywater and nasty bugs like e-coli, pictured on the right, remind us we need to be careful. So here are SurviveLA’s rules to follow when using greywater:

  • Do not apply greywater to crops that you will eat raw, such as strawberries, carrots or lettuce. Using greywater on any vegetables is somewhat dodgy in general for heath reasons, but greywater is fine for edible plants such as fruit trees where the crop is far from the ground and the risk of direct contamination by contact with contaminated water is low.
  • Do not apply greywater to lawns (lawns are evil anyways) or to the foliage of any plant as this can cause a microorganism growth party. Remember that greywater is treated by moving through soil.
  • Greywater tends to be alkaline, so avoid using greywater on acid loving plants such as citrus, ferns and other forest plants (pretty much anything that grows in the shade).
  • Occasionally irrigate your plants with fresh water to prevent the buildup of salts from soaps and detergents.
  • Do not distribute greywater with a sprinkler as you don’t want the potential bad stuff becoming airborne.
  • Do not use the water from your washing machine if you are washing diapers (gross!).
  • Do not allow greywater to stand as it will quickly become the perfect habitat for anaerobic bacteria which will quickly turn it into a stinky, mosquito and fly infested pool of blackwater. Plan a system that will, ideally, use your greywater immediately.
  • Use only detergents and soaps designed for greywater systems such as Oasis Biocompatible Cleaning Products.

Bucket Flushing

SurviveLA is researching greywater systems and today we’ve got our first tip on recycling your water. First a definition. Greywater is the waste water that comes out of your shower, sinks, and washing machine. Blackwater is the icky stuff that comes out of your toilet and because of the risk of contamination it should not be reused. For now we’ll lump the kitchen sink in with the toilet since food scraps, particularly for meat eaters can quickly turn your greywater into rancid blackwater.

Greywater systems range from the simple to the complex and we’ll start with the cheap and easy — bucket flushing. Simply keep a bucket next to the shower and collect the water that you run before the shower gets hot. Since you haven’t even stepped into the shower this water is pure water, and not even technically greywater. You can use this water on plants or to flush the toilet manually by pouring it directly in the bowl.

It’s also possible to disconnect the bathroom sink from the sewer system and send the water into a bucket that you keep under the sink. This water is greywater since it’s contaminated with soap and toothpaste, so don’t let it sit around for long or it will get stinky. If you disconnect your bathroom sink, make sure that you keep water in the trap (that u-shaped pipe), otherwise unpleasant sewer odors will fill your bathroom. Alternately, you can cap the sewer pipe or install a diverter valve.

One last warning. Apparently around twenty-five kids drown in buckets every year in the US, so don’t leave buckets unattended if you have little ones, though the danger is mostly from larger five gallon buckets.

So flush the SurviveLA way — bucket flush!