Tuesday, August 31, 2010

Water: Cities vs Environment.

On twitter a while back, comments where raised about legal dams in the Upper Darling part of the Murray Darling Basin. There where some city tweeters who thought this would fix their water problems.

They have a mind set that farming isn't part of the environment and takes water away from it and them. This forgets a couple of factors. On a lot of land, farming is the environment. The water that gets to the cities come from three places. The high wet areas of the land, where that is always an excess of water for part of the year, especially the melt in early spring. Big rain events. The last is degraded lands in the rest of the basin.

It's these degraded lands I want to comment on. These lands are degraded due to imported practices and over use. As farmers improve practices and adopt more natural methods, like native perennial pastures, the water yield will continue to fall (even assuming no global warning reductions) back to natural levels. So farming isn't a source of water for the cities, if it's allowed to evolve and improve it will reduce water availability.

Maintaining water yields for cities means retarding the improvement of the farming environment. Better that cities learn to not over tax their local environments too. Rain water tanks all-round!