Household Water - DIY Water Harvesting and Recycling

Introductioncheap and easy to handle and install, but take up
The great thing about working to optimize the wayspace. Underground tanks are the opposite.
you use and collect water for your home, is that youGetting Started
get to feel as though you are doing somethingYou can calculate the likely rain available using
practical to improve the environment without makinginformation from your local Meteorological Bureau.
sacrifices, but actually benefiting your household.They will give you average rainfall each month. For
Backgroundexample, in a location like Melbourne, it rains about
Initially I was interested in building DIY solar hot600mm each year, with rain pretty much uniform
water panels. I found a community group who had athrough the year. If your roof area is 200 square
jig made up for pressing the grooves into the coppermetres, and you want to catch it all, and assuming
sheet to locate where the copper tubes are to beyou want to store enough to water your garden for
soldered. They also had a jig for positioning theabout a month, the tank volume needs to be about
½" holes in the 1" header and footer pipes.1,000 x 200 x 0.6 / 12 = 10,000 litres. This gives you
This was a great start, and then I silver soldered the10,000 / 30 = 333 litres per day. If you add this to
risers into the 1" pipes, and soft-soldered the risersyour grey-water, originating from mains water supply,
onto the sheets. After painting the copper sheet andthis gives you about 500 litres available for the
pipes with black-board paint, I built a box with timbergarden. However, it is less if you use the tank water
sides and a plywood back, with fibre-glass insulation,in the laundry.
and assembled it with a glass sheet over the top,Becoming Proficient
sealed with silicone.It may take a while to get all the skills you need, and
I bought a second-hand water tank, and mountedthis is where the net can be useful. There are lots of
them all on a frame screwed through the metal roof,government authority sites with heaps of
into the timber roof frame. The panels are still goinginformation, as well as dedicated societies with lots of
strong 30 years later.technical articles. Just have a go, and get started.
Success in Home Water ConservationThe skills will build up as you go.
The three main things you need to know in order toHow Much Experience Is Needed?
successfully develop your home water program are:You can do most of this sort of work without any
how much water of what quality you need; how toexperience, except for the electrics, that must be
harvest and store rain water; and how to safelyleft to a qualified electrician, and any plumbing to do
re-use waste water.with sewage. Of course, working at heights, doing
While we only need a few litres each of drinkingconnections to gutters for example requires good
water each day, cooking water should be potablesafety practices.
quality, and laundry washing water should be freeExamples
from impurities that would stain, such as ironWith my grey-water system, I have a thriving
deposits. The next quality down would beorchard of about 14 trees, providing organic fruit
grey-water for vegetables and fruit trees, but only ifover the summer and autumn. The underground
it is applies via dripper, and not sprayed. Septic tankwater tank, just coming on line, collected 7,000 litres
effluent is suitable for fruit trees, but must be appliedover one weekend of rain, from a roof area of 200
via underground methods, such as gravel trenches,sq m.
covered with soil. Ornamental plants and trees canThe Best-Kept Secret About Home Water
use any standard of water in regard to cleanliness,By zoning your plants in the garden-planning phase,
however salt, nutrient, detergent and particulateyou can optimize your water use, by having the
content can be problems, as they can also be for thefrequent- drinkers all grouped on the same pipe, and
other uses.the bigger trees on a separate pipe. (I think you
A ¼ acre block with a big ornamental gardenshould also go for the biggest tank you can afford).
of deciduous trees and shrubs in a temperate climateCommon Problems
requires about 2,000 litres per week in the summer.Regulations require that your grey-water doesn't
You can calculate the water demand for a tree usingseep onto the public nature-strip or roadway, or onto
the British Standard BS5837 1991, which gives ayour neighbour's property.
formula including the tree type and canopy diameter,Evaporation is a huge waste of water in the garden.
the local evaporation rate. The watering frequencyA thick layer of mushroom compost and pea-straw is
depends on the soil type and how much soil isbest in the vegetable patch and orchard (because
available to each tree. Typically, a small tree takes 20this will break down fast to provide nutrients for the
litres of water a day. Vegetables' water demandplants), and wood-chips are best for ornamentals.
depends very much on the variety and the weather.Blocked gutters are a problem, and regular
Partial shading is recommended for some varieties inmaintenance is needed. Leaf-guard over the gutters
the heat of summer.is great, but quite expensive. In-line leaf-diverters are
Grey water systems are reasonably cheap, off thea good option. But they also need regular clean-outs.
shelf, and government rebates help off-set the cost.Tank systems need mosquito-proof inlets and outlets.
However, to qualify, you need a plumber to install it,If you are going to drink rainwater, your roof can't
and that takes up a lot of the rebate. An economicalbe zinc-alume, as the aluminium is not good for you.
DIY system, which I have found to work very well,You have to be aware of animal and bird droppings,
consists of a 200 litre plastic barrel ($30.00) with aas well as pollution fallout. A first-flush diverter will
pump incorporating a float switch. You cut a hole inhelp a bit here.
the top and lower in the pump. Locate the barrelA Great Investment
under your discharge pipe from the laundry andWhile it may take a bit of planning, money and work
bathroom (not the toilet). As a filter, you double up ato get your system up and running, once it's done,
pair of panty-hose to give a two-layer filter, and putthere is just a bit of regular maintenance, and you
it over the end of the pipe, taping it in place. Everyhave a wonderful feeling of accomplishment, that
few months, replace it. The pump is connected toyou are doing your bit, and getting substantial
20mm black poly pipe for distribution to the garden.benefits as well.
A secondary filter - a commercial one- is needed ifStaying On Top
you use dripper hose. Don't buy the recycled rubberTo keep on top, you need to monitor your usage, to
hose, it goes brittle after a few years, and leaks andensure you don't just use more mains supply water
breaks. For recycled water, use the purple one, as itsas well as your recycled and harvested water. You
holes are bigger, and less likely to clog. Every nowneed to keep the system clean: flush the drip lines
and then, open the end of the dripper hose, andand clean the roof gutters regularly. You also want to
flush it out.cycle the roof water with your recycled water, to
Rainwater is easy to collect in plastic tanks, which arereduce the build-up f salts in the soil.