Drainage and
sewerage are made lower cost by making them follow the
topography. Thus sewers do not need to be buried deeply, digging is reduced, and pumping of sewage is avoided as the sewers follow the natural drainage paths. In a lecture for
Engineers Without Borders (UK), Himanshu Parikh explained that his research into the growth of slums had led to the realisation that slums always develop along natural drainage paths. Therefore, the cheapest way to provide sewerage to a city is to build major sewers through the slums and connect the higher (and usually richer) areas of the city to them. This then provides sewerage to the whole city for lower costs than just providing sewerage for the rich areas. This approach opens up funding from local and national governments, which can then be matched by donor funding if necessary to construct sewerage and water supply systems. The cost savings provide leverage to get the local government to provide
tenure to slum dwellers. The slum dwellers, once given tenure, are willing to spend their own money on developing the slums as the risk of losing their investment is removed. Microcredit schemes mobilise this funding and allow slum housing to be connected to sewers and water systems and for slums to be landscaped and lit. The evidence from Indore City is that two years after the upgrade programme the slums are no longer recognisable as slums. ==Awards==