The short to medium term outlook for the water supply is fairly bleak in Canberra because of the fires.
Bendora and Corin dams in the Cotter catchment are unusable because of sediment running from bushfire-affected land. They will remain unusable for at least a year until new filtration equipment is installed at Stromlo.
So there is only Googong to serve the city. Right now, Googong Dam on its own has enough water to supply Canberra for a year without any rain. But there is not enough pumping and treating capacity too get water out of Googong, filtered and sent to Canberra to keep up with summer demand.
From now to the first day of summer the rain can fill all the dams but we will still have Stage Three water restrictions – which effectively means no outdoor watering.
Alas, we have a unitary system of water supply so all water delivered to Canberra households has to be treated to drinkable level even if it is destined for gardens.
The pumping and treatment plant at Googong can deliver just 180 megalitres a day. We thirsty Canberrans, however, consume about 240 megalitres. Even with Stage Two restrictions we did not get below 180 megalitres a day average.
Googong’s pumping and filtration can be upgraded to pump an extra 50 per cent or 90 megalitres. It will cost $13 million and take a little under a year – again, too late for the coming summer.
Stage One and Two were easy, just put your sprinkler on at night and don’t wash the car. Compliance was not difficult so was widespread. Stage Three is the big hit. No sprinklers. Just hand held hoses at night. Canberrans used to automatic sprinkler systems will have a grim choice: let the plants die or stay up for hours watering or break the law – unless we have good regular rainfall every week on Canberra gardens throughout the summer. Not likely.
That’s the quantity but what about the quality.
Googong water is nowhere near as good as the Bendora and Corin water from past years. The Bendora and Cotter catchment was mostly wilderness – no farms, no pollution. The Googong catchment has a lot of farmland. No matter how much you filter and treat, it does not taste the same.
At the rent National Wine Show experts and wine tasters did a blind tasting of the water from all eight capitals. Canberra did not come in the top three. The same thing was done a decade ago, but the test included rain water. Most tasters then thought Canberra’s water was the glass containing the rain water. It was tops. The fires have put an end to that for perhaps decades.