1. To improve the ground water table.
2. Lower cost for public sewage system.
3. Lower cost for investors.
4. More green in urban areas.
5. Less impact for the nature.
6. Reduce urban heat island effect by evaporation.
The dimension of the sewage
pipes can be reduced, because the quantity of water is much lower
and the
remaining water run-off is delayed..
Why
do we need Storm Water Management?