The North Atlantic Island of Bermuda has no fresh water springs, rivers or lakes. The colorful pastel limestone houses are equipped with white roofs in order to harvest rain. They also have small steps on them, which slows down the heavy rainfall, which helps the gutters collect the water and store it in tanks below the house. As there are no permanent steams and the lakes are brackish, the system was forced on the early settlers. It later became enforced in house-building regulations, for each square foot of roof space; all houses must have eight gallons of tank space.This design has many benefits. Being made of limestone means it is heavier and not easily shifted by hurricane as well as having anti-bacterial properties.