Reply to Lindsay Leake (December 11): 

Lindsay, the BOM data shows 2010 MDB annual rainfall was 808mm (La Nina + negative IOD) and 1956 rainfall was 786mm. But by 2010 the catchment was very dry with the preceding nine years under average rainfall, while 1950 to 1955 had good rainfall with a very wet catchment at the start of 1956 and therefore very high runoff. Again check the BOM rainfall ...