Hi Converse,
I also feel it is the developers getting greedier and as such covering every square inch with concrete or bricks.
I remember a time when Councils had regulations on how much of your land you were allowed to cover and what percentage had to remain open to absorb water. This was all about not placing so much strain of the storm water infrastructure, but now it seems that every amount of land is covered and thus all run off feeds into the storm water system after the piddly little rainwater tank is full.
Cheers,
BB.