Monday 18 August 2008

permaculture - using water rsourcefully and respectfully

I've been meaning and meaning and meaning since June 25 or so to write up the last bit of my permaculture course. And here we are .. WATER .. as we, as humans, are 70 per cent water - taking care of the limited water on our planet and ensuring that we use our resources well is so important..

The average American uses 100 gallons of water per day - of which only 2 gallons is used for drinking. Half of all water used in suburban areas goes into watering gardens. Where I am now, on Cortes Island, there are signs up saying that every flush uses 6 gallons of water. Baths, washing machines, dishwashers etc also take a lot of water.

There are three ways we can be more mindful. The first is to recycle our used water, so that it becomes a resource, rather than a waste product.

RECYCLING WATER

Have you heard of the term greywater before? This is used water that's not too dirty to re-use - such as the water from bathroom sinks, showers, baths, washing machine and so on - with some rechannelling this can be used for washing cars, watering plants and so on. This changes it from being waste water to a resource. In Australia, which has been in a drought for several years, it is illegal NOT to have a grey water system in your home.

Black water refers to the water from kitchen sinks and dishwashers (which would contain foodscraps) and toilet water. Through innovative systems such as the Living Machine at Esalen this water can go through some fairly natural filter processes, to zap the bacteria, so it is good enough for irrigation.

The second way is to capture rainwater, which would otherwise run into drains and end up as a lost resource in the sewer system.

RAINWATER HARVESTING

Another great way to conserve resources is to catch the rainwater that falls onto the roof and channel it into a tank. If you're interested in rainwater harvesting, here are some factors to take into account:

RAINWATER - what's the max of rainwater that falls in a day? What sort of seasonal rainfall patterns are there? Is the water drinkable? Is acid rain a problem where you live?

ROOF - is the material something you would want to drink from? Asphalt and tar roofs will contain petroleum. PVC, vinyl and plastic are also toxic, especially when hit by the sun. Commercially bought woods or canvases with fire retardant are also toxic as is concrete that contains fly ash. If the roof has old paint containing lead, that's also toxic. You'll be wanting a roof made from these materials to rainwater harvest:
1 - Slate (if it's local to your region)
2 - Tile (although some algae will form in it)
3 - Baked enamel
4 - Painted steel
Although they are non-toxic, living roofs are not good for rain harvesting as the plants will soak up too much of the rain.

You'll also want to have mesh over the gutters to filtrate the water and keep leaves and debris out of it.

A house with a 1000ft square area will capture 600 gallons of water on its roof for every inch of rain. California has 30 inches per year which would provide 18,000 gallons.

The average suburban American uses 36,500 gallons per year (100 gallons per day). When rainwater harvesting, we become more respectful and resourceful about how we use our water.

The third way to conserve water (and this may seem radical to some) is to minimise the amount of water needed to carry our pee and poop into the sewage system.

Urine in the morning is 18% nitrogen, which is wonderful for plants. There is also the "mellow yellow" practise of letting the toilet bowl fill with urine and only flushing when it gets stinky or when there's a number two coming in. Six gallons for every flush is a waste of a lot of precious water - especially when our pee could be making the plants happy!! For advanced practitioners of sewage consciousness, there is the humanure system for poop - whereby you dig yourself a hole in the ground - put earth/ seaweed/ sawdust etc on top of your doings and when the hole becomes full, you seal it up and move your toilet elsewhere. After 2 years, the material has composted sufficiently for use on non-edible plants.

MISCELLANEOUS WATER THINGS ..

1 - Plastic paddling pools are also toxic, unless made out of HDPE plastic.
2 - If you want to minimise mosquitos in your garden pond, put a fountain in - as this will keep the water moving, rather than stagnant

No comments: