The major problem in the urban context from the point of view of groundwater is its contamination due to release of untreated sewage into the ground and its exhaustion due to excessive withdrawal. A very good solution to this problem is decentralised treatment and reuse and recharge of both grey and black water so as to both do away with the problem of untreated sewage and also increase the availability of groundwater. Find out how Rahul Banerjee implemented a solution in his house in Indore, Madhya Pradesh.
Check it out on scribd
You can also watch what Rahul has to say here (YouTube)