Tram Town
Sunday, March 27, 2005
| Category: Water We saw the Thomson dam last week and crossed many of the great rivers of Gippsland. The rivers were all just about bursting their banks so they are not currently starved of flow. Perhaps that is just a seasonal thing. Looking at the Thomson dam, it sure as heck looks, based on vegetation, as if it has never been much higher than it is at the moment but I have struggled to find historical data, maybe it will never fill up. The level at the Thomson is important when looking at the regularly published water storage levels. We are currently deemed to be 57% full. [shot of Semi running off to his spreadsheet][shot of Semi coming back] If we take the Thomson out of the equation completely, we would be at 68%. If we include the Thomson declaring its current level to be "full", we could consider ourselves to be at 80% of capacity. Now it is dishonest of me to say the 80% figure could be realistic if we are to believe that levels in 1997 were at 80%. That would imply [spreadsheet gag repeated] that the Thomson in mid 1997 would have had to have been at a minimum of 67% full as opposed to 50% full at the moment (I could send you the spreadsheet if you wanted). Note that the calculated 67% level is a minimum and it assumes that all of the other dams were chocka (not likely!). The problem here is that we must have dropped the level of the Thomson by at least 20% of its capacity and 30% of its actual storage since late 1997. How is it that over the period from 1982 when the dam started to fill until 1997 our net usage of Thomson water was -700 gigalitres and our net usage 1998 to 2004 was +300 gigalitres (2004-2005 so far is -100 interestingly). That is more alarming even than the state government makes out. They says it's caused by an eight year drought but Warwick Hughes has data and a picture that suggests otherwise. I don't know what to think. I am constantly reminded in all of this Victorian water business of the scenes from Chinatown where water is deliberately let to run away for political reasons. I reckon we need to get J. J. Gittes on the job here in Melbourne. He might be able to find if the recent volatility in storage is due to the fact that "around 54% [of outflow] has been released for maintaining environmental flows and supplying irrigation areas downstream". It all looks like an attempt to implement the seriously flawed Green Religion notion of Eden. UPDATE: I was way too cynical in this post. The Thomson has quite recently been full as noted here. |
