Smog moves west as Sydney grows
Smog levels are down over inner Sydney, but the outlook in the expanding western suburbs is causing much concern, particularly in the Hawkesbury Basin, Parramatta River Valley and Liverpool Basin. The only real hope is to control the level of photochemical smog formation through a lowering of the emissions of nitrogen oxides, currently produced by motor vehicles and factories. However, lowering nitrogen oxide levels will be a far more difficult strategy than existing pollution controls.