Since May’s rain there’s been lots more sunny days, until this week. The satellite image of the cloud cover on Thursday morning showed a large portion of WA covered in thick cloud. This produced a nice downpour of 22.2mm for Perth, with June’s rainfall so far now 43.6mm. As a result we’re no longer having the driest January to June on record , but the rain didn’t last. It’s been fine since then and the forecast is for more un-June sunny weather until Thursday, even if the temperature has dropped.
Last winter I blogged about Perth’s water restrictions:
Only in October 2007 were restrictions placed on summer bore use, for irrigating residential gardens, parks, sporting fields and golf courses. Theoretically restrictions shouldn’t be needed in winter months because you’d think people would realise that irrigation isn’t necessary when it’s raining. Sadly, I’ve seen sprinklers in use at Curtin University and gardens near my house, when it was raining.
There are still no restrictions on winter water use in Perth, but the State government is threatening restrictions due to the lack of rain so far this winter . (Last week’s rain only slightly improved things – we’ve still had substantially less rain than the average.) The Conservation Council of WA is urging the government to impose a total winter sprinkler ban. Water Resources Minister Graham Jacobs is considering this, and will make a decision in the next two weeks after monitoring water use. I hope a ban is implemented because sprinkler use in winter is wasteful. The lower temperatures and daily dew in the morning mean plants receive water even when there’s no rain. When there’s lack of rain, as currently with days or weeks between rainfall, hand-watering is adequate. (I’ve been doing this for my vegie garden.) Expanses of lawn (in the backyard, parks, ovals, golf courses) do not need irrigation in winter, even at times like this. And of course, irrigation while it’s raining is still happening this winter. In May I was driving to the Hyde Park Hotel and the park down the road had sprinklers going, while my windscreen wipers were in action. Someone at the local council forgot to flick a switch.
In order to limit water use, the best way is to reuse it. Households and business should be encouraged to reuse grey water (from the kitchen, laundry, bathroom) and processed black water (sewage) for irrigating gardens and flushing toilets, as a start, but more helpfully all water needs. With the right infrastructure sewage (plus grey water) can be easily processed onsite (in houses, businesses and industrial locations) to a high quality . To achieve drinking quality further treatment is necessary and is only possible at large scale treatment plants .
Our society has a psychological aversion to using processed sewage for anything, let alone drinking it. This was a helpful trait in the past when cholera and typhoid were ever present dangers when it came to sewage contamination of water supplies (and still are dangers in too many parts of the world). This aversion was amply demonstrated when residents of Toowoomba, Qld voted against a proposal to use processed sewage for Toowoomba’s water needs, including drinking water .
I often mention the following statistic from the ABS when I blog about water use: household water use makes up only 11% of total water consumption . Industry is the main culprit and agriculture uses 65% of Australia’s water. While we live in the city and suburbs of Perth and think agriculture is far away in “the country,” the semi-rural outer suburbs of Perth grow and farm a lot of our fresh produce and (particularly in the Swan Valley) irrigate from the Gnangara groundwater mound where the majority of Perth’s water comes from.
Basically this means what we do at home makes almost no difference in terms of total water use :P What it does impact is our peace of mind. I feel like I’m doing something when I re-use and conserve water. The Conservation Council of WA realises industry is the main culprit  and we all need to lobby government to legislate for industry and agriculture to cut their water consumption, particularly by reusing grey water and processed sewage. A huge wastage in this area is stormwater, which goes down roadside drains and into wetlands, the ocean, wherever the drain comes out. Diverting and processing (if necessary) this for industry and agriculture is a perfect recycling venture. When Newcastle City Council, built the new Wallsend District Library the design included on-site stormwater retention for toilet flushing and irrigation of the garden surrounding the library. Ideas like this should be included in Building Codes so every new building has such design elements.
- Calautti, Lisa (2009) Overnight rain ends June sunny spell The West Australian, 11 June
- Banks, Amanda (2009) Threat of winter sprinkler ban The West Australian, 10 June, p.3
- Troy, Patrick (2001) “The management of water in Australia’s cities” Dissent, no.7, p.28-32
- Recycled drinking water (2008) Choice magazine, January
- Frew, Wendy (2006) Poll result means rising water bills, Turnbull warns The Sydney Morning Herald, 31 July
- Australian Bureau of Statistics (2006) Water Account, Australia, 2004-05, report no. 4610.0