To hear the NSW government claiming it will walk away from the Murray-Darling Basin Plan after last week's disallowance of a regulation to reduce environmental allocations is to witness institutional chutzpah of the highest order.

NSW has never had much interest in fulfilling its responsibilities in relation to the basin, and it has basically acted as a cipher for irrigators who want to extract as much water as they can from the system. On some rivers in the NSW part of the system, NSW's departure from the plan will make little difference because it was barely doing anything to implement the plan in the first place.