Saturday, June 09, 2007

New England's Wild Weather

Photo: Sydney Morning Herald. The bulk carrier Pasha Bulker forced aground on Newcastle's Nobby Beach. Story.

On the morning of Friday 8 June, Tamworth's Northern Daily Leader reported on a discussion that if no water flowed into Chaffey Dam, Tamworth's businesses would be forced to close in nine month's time. The Chaffey Dam, Tamworth's main water supply, lies on the Peel River whose headwaters are a short distance away in the south-western edge of the New England Tablelands around Nundle (and here).

Later that day, a low pressure cell off Newcastle unleashed cyclonic conditions and torrential rain on Southern New England.

Conditions since can best be described as chaotic.

Heavy rain led to flooding. High winds created chaos during which the Pasha Bulker was driven ashore on Nobbys Beach. Two other bulk carriers just escaped. In all, an interesting experience after drought.

Whether this storm will be sufficient to solve Tamworth's water supply problems is unclear. Rainfall data is not yet available and in any event follow up rain will be required. Still, signs are now encouraging that the drought that has gripped the western side of New England is coming to an end.

Postscript 16 June

I did not write a full post on the impact of the wild weather on the Lower Hunter itself because it was so fully covered elsewhere. I was surprised, however, at the scale of the damage.

Major Hunter floods are not uncommon. Yes, this was the biggest downpour for thirty or so years, but even so. I was left wondering about changes in the human especially built landscape over the last thirty years, including things such as changes in the electricity distribution system.

Was it just a case of localisation, very bad weather in a narrowly defined location, or did changes in settlement patterns contribute to the scale of damage?

Returning to Tamworth, I see from the Northern Daily Leader that the weekend rain nudged Chaffey Dam's storage up from 13.9 per cent to 14.9 per cent.

Chaffey Dam's storage level had reached an all-time low of 13.9 per cent last week – prior to 2007, the lowest previous level was 19 per cent in 1995.

The dam's volume has not reached 100 per cent since 2002. When it does reach full capacity, water covers an area of 542 hectares and can reach a depth of about 30 metres. It now sits at about six metres at its deepest point.