Projections currently indicate a potential drop in South Eastern Australian rainfall of as much as 50% by 2100. The coastal fringe down as far south as Sydney is not expected to be as badly impacted. However, the winter rainfall is expected to reduce in favour of the summer (summer rainfall up 50% by 2100). There is a question as to whether dams such as Mangrove Creek Dam and Warragamba will get less rain due to being behind the escarpment.

Impact type                             2050                             2100                          2300

                                          Low        High                Low        High             Low        High

Average                            +2%       -10%                +5%       -15%

[Assessed Aug 2010]