It's a 1000-litre Devan tank in grey. Currently gracefully on its side next to the trampoline :)
|To those of you interested, its capacity is exactly the same as the white 'cube' tank next to it: a thousand litres.|
Once set up, it will go in front of the house where water will be used for gardening. You see that white downpipe in the corner of our house? That. We'll connect the tank to that downpipe.
|Once set up, the tank will be almost the same grey colour as the windowsill next to it.|
|Sticks are piled in the corner to discourage our neighbour's cat from using that are as his toilet. Bloody cheeky creature!|
|Planter-boxes in various stages of setup: back one established, middle one just filled with compost (and some kale which, turns out, does not like to be transplanted) and front one being base-filled with hedge clippings before compost comes in.|
Today me and my husband had a laborious (but necessary) discussion over setting-up details. This ensued:
Because that specific downpipe drains the smallest are of our roof (only about 20 m2), we discussed whether we are 1) better off putting the tank elsewhere, or 2) changing the gutters slightly to increase the drainage area, but in the end... we left it as it is. We will need water in front of the house, and there are electricity / sewage / water service lines running elsewhere in the front yard - on top of which, ahem!, it's better to not put 1 tonne of weight - so although our drainable roof area will only be 20 m2... it'll have to do.
Over a year, that downpipe receives more than 23,000 litres of water (Invercargill has 1,150 mm of rain annually). We won't collect all of it, of course, because 1) we will 'lose' some water to first-flush-diverting (I'll explain in a minute), 2) in summertime, the tank will run dry because we will use water faster than rain can replenish the tank, and 3) in wintertime the tank will overflow because there is more rain than we need - but for the moment, it'll just have to do. We just need to start somewhere.
We don't expect to use this water for drinking. However: we are putting in place some precautions so that, if need be, the water can be drunk. (Especially if it gets treated or filtered with camping equipment afterwards.) The precautions are:
* 20-litre first flush diverter which will 'siphon off' first 20 litres of any rainfall that comes down our gutters. (First water is always the dirtiest because it brings with it dust, bird poop and other cr#p! that lays on the roof.) Once the 20-litre mark is full, cleaner water will flow towards the downpipe.
* Another debris-filter as part of the water diverter: it removes sticks, leaves and other larger items before the water can flow towards the tank.
The tank is made of dark, thick plastic, so it will not receive sunlight and therefore, won't have algal growth inside it, but once a year, it'll be good to have it cleaned. There are access hatches at the top.
We will need to construct a small concrete base for it to sit on. As projects go, we will probably encounter problems as we undertake this work, but... also, as projects go, we will get it done. Eventually :)