Re: The Climate, Environment and Energy Thread
Reply #708 –
A couple of points about levees.
First of all, levees don't prevent flooding. They constrain river flows and cause more severe flooding where there aren't levees. The recent Maribyrnong River floods and the Flemington race track levee is a classic example of that. The water has to go somewhere.
Secondly, the Mitchell Shire Mayor was on the wireless this morning and was asked why the Shire decided not to proceed with the construction of more levees. She explained that the Shire's cost-benefit analysis showed that the cost of constructing more levees far outweighed any benefits they may provide in the foreseeable future. That is, the decision was made on purely financial grounds and not because of the bleating of the "metro left greeny types". I reckon that the Mitchell Shire ratepayers who don't live on a floodplain would be pretty happy with the Shire's decision.
The bottom line is that infrastructure on flood plains will be subject to inundation regardless of how many dams and levees are constructed. If stuff has to be built on floodplains, it should be flood-resilient at worst. Retrofitting buildings to make them flood-resilient makes a lot more sense than building more and more levees.