Peak flow

The housing density in my suburb is increasing.
Formerly on a eight hundred square metre allotment there would be a single storey 3 bedroom house with a gravel driveway. Sixty percent of the area would be garden and trees. The downpipes from the roof would discharge onto garden or into a rainwater tank.

After development this same area will host two two-storey houses each with five bedrooms and a concrete driveway and a very small garden. The downpipes discharge onto the street.

The roofs and concrete driveways are impenetrable (I would hope) to rain so it must flow off. This makes the peak flow after a storm higher than before.

The solutions include rainwater tanks, soak pits and using gravel instead of concrete. Also leaving room for a garden would be nice.