In urban areas there is always shortage of water due to the growing industrialization. But the irony is that the roads are always flooded with water during the rainy season.  As a result the quality and quantity of ground water is affected. This scenario is due to the lack of proper water management. If the rain water is properly utilized the water needs of many people can be met. Most of the cities receive rainfall in short spells. Due to this, most of the rain falling on the surface tends to flow away rapidly leaving very little water for the recharge of the ground water. The urban water scenario has been worsening as the cities have been neglecting the traditional water harvesting systems. Rain water harvesting or capturing the runoff is one of the solutions to the urban water crisis. In places like Chennai, Bangalore and Delhi rain water harvesting is a part of the state policy. Cochin builders are also trying to provide rain water harvesting facility in many of their projects. Many other countries like Germany, Japan, United States and Singapore are also adopting rain water harvesting.
 
Rain water harvesting offers an ideal solution in areas where there is inadequate groundwater supply or places where the surface resources are lacking or insufficient. It also helps to utilize the primary source of water and prevent the runoff from going into sewer or storm drains, thus reducing the load on treatment plants. The urban flooding is also reduced. Water can also be recharged into the aquifers thus improving the quality of existing groundwater through dilution.