The Centre for Science and Environment, New Delhi, has conducted for the first time in India, a detailed study of an unplanned, low income, urban housing settlement, Sangam Vihar, in South Delhi, which has a population of about a million people packed densely into an area of about 5 sq. kms. It is a detailed study done with a rigorous methodology and worth a read. However, there are a few points on which it is deficient. First, despite having separately estimated the overall storm water flow and the peak flows due to rainwater that is falling in the area and also the grey and black water being generated in addition to the existing and future water demand and supply, a water balance estimation has not been done either at the street, block or the whole colony level. Second, the possibilities of rainwater harvesting and recharge and grey water treatment and reuse or recharge at the household and street level have been ignored altogether possibly from the assumption that these are not possible in a congested locality. However, it is always possible to harvest/recharge rainwater and treat and reuse/recharge grey water at the household and street level, regardless of how congested and narrow the streets are. There are very simple and cheap technologies for this and the only thing required to do this is to build awareness among the residents through workshops and provide funding support where needed.
Shashi Bhatnagar
3mo
rahul banerjee - there is another good study by Water, Environment, Land and Livelihoods (WELL) Labs - Shreya Nath for a town in /karnataka.
Prof-Maritime Studies, Vels U & Head- Environment, Vigyan Vijay- NGO.
3moIf septic tks are done for each home's OHOTs, then adapt them as Dewats Can have Elephant grass sp for last stage phytoR. In the vicinity has a large School- (Hamdard) campus too