Sunday, January 21, 2007

Where did the water go?

The water levels of Melbourne's dams are now published daily, and a surprising number of people are well informed on the levels. Today "The Sunday Age" had a story about the bit dry (it has actually rained for two days now) and mentioned that the dam levels fell 0.1%, in a sidebar, strangely the article only indicated 8mm of rain in the past 24 hours and the rainfall section back a bit only showed 1.5mm. I can tell you it rained more than that. Checking on the net I could see that the average around melbourne was 24mm and some place over 40mm in some places (mainly the areas were our water catchments and dams are). This which is closer to what I expected.

So what is going on here. Well I found one likely cause, the news paper story is probably not basing its discussion on up to date data. It appears to be based on Melbourne Water's website (which at the time of writing had not been updated for the recent rains.)

This melbourne water conserve water website is interesting, it gives all the dam levels and also mention that melbournes consupmtion (on average, and that means without water restrictions is 500 giga litres, which is 500,000 megalitres). The full capacity of our dams from this source is 1,773,000 megalitres which is about three and a half years supply. We are now down to 66,577 megalitres and that thens leave close enough to 1.32 years of unrestricted use. Sorry haven't managed to track down the about of water that is expected to be saved by the restrictions.

The inaccuracy of the newspaper report asided, does all the panic about water and water restrictions really seem like we are despeate and about to run out of water? Over a years worth does seem ok to me when much of northern victorian has virtually none left, but to me it is even harded to justify expensive TV adds to dob in water wasters.

Or is the urgency perhaps more to do with political spin!

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