Rainwater is amazing because it’s naturally soft, free of chlorine and other chemicals, which are present in the tap water supply, and you will save money on your water bill. It is super simple to harvest rainwater – all you need is a slanted roof, gutters and a downspout, a storage tank, a mosquito screen and lid, and a spigot or hosepipe. If you want to collect more rainwater off your roof, you can connect several storage tanks via pipe in a row. You can use your rainwater for drinking water, feeding your garden, or connect it to your household plumbing system.
Be sure to calculate the amount of rainwater you’d harvest according to the area of your collection surface. There are now plenty of web-based rainwater collection calculators available for your convenience.
When it comes to implementing a greywater system, it’s best to use it for your garden plants. To keep things simple, you can pipe it directly onto your lawn, or you can store it in a settling tank, with a pipe at the top that connects to your irrigation or garden watering system. Keeping it in a tank allows the solids to settle at the bottom, so they don’t clog up your pipes. But this also means you’ll need to pump out the solids once a year. You can add the settled material to your compost system.
Milkwood Farm in Australia has a really cool mulch pit greywater system, where they hooked up greywater from their laundry and outdoor sink and piped it into several different mulch piles. Next to each mulch pit they planted a beautiful shade tree that provides food for people and animals, as well as biomass for compost, fuel, and other uses. They plan to grow other companion plants near the tree in the future. Companion planting is the act of planting several plants that benefit each other in the same space.
There are other ways to filter greywater for reuse, such as through a wetland system, which uses a bed of reeds to filter the greywater. The reeds take up bacteria and pollutants, leaving the water clean. But instead, the folks at Milkwood Farm chose to keep it as simple as possible and still let nature do the work. The greywater helps compost the mulch, water the tree, and vitalizes the soil microbial community.