An additional on flooding: When Rainfall * Area >= SoilAbsorption(See note) + WetlandAbsorption + ArtificialDrainage the end result is flooding. Essentially t

An additional on flooding: When Rainfall * Area >= SoilAbsorption(See note) + WetlandAbsorption + ArtificialDrainage the end result is flooding. Essentially the left hand side of the inequality has been slightly increasing because of climate change, but we're chipping away constantly at the right side of the equation in three ways. (1) More and more soils in American metro areas have been covered by impervious surfaces for development. (2) More wetlands are being destroyed for development. (3) Artificial drainage is being under-built. Drainage is generally built for 1 in 100 year events but the rate of urbanization is increasing the magnitude of flooding. (Drainage is only a problem for the developer that hasn't sold what they're building.) Note: Soil has a finite capacity for water infiltration.