Lack of sanitation in cities

Rapid expansion of urban populations presents problems for the provision of basic services to all. The rapidly growing peri-urban communities are often ignored by urban systems that may have been designed many years before the location and rate of growth was anticipated. Poor inner-city zones with high-density populations remain unplanned, with only skeletal infrastructure. In general, the rich receive these facilities and the poor do not, but the ensuing problems can affect the whole population. Particularly where squatter settlements proliferate at the outskirts of cities, a common occurrence in developing countries, access to sanitation (or drinking facilities) may be entirely lacking or inadequate. In humid zones, inadequate drainage, open sewers and broken, de-pressurized mains in urban areas can lead to the rapid transmission of water-borne diseases. Cities in arid and semi-arid regions pose another complex of environmental problems, including depletion of distant fossil water sources, aquifer pollution, and ground subsidence associated with local aquifer extraction.

The UN-mandated Water Supply and Sanitation Collaborative Council describes typical water supply and sanitation problems in expanding cities in the following way: (1) Grossly inadequate sanitation provision creates a health-threatening and offensive environment, particularly in low-income settlements; (2) Surface water sources are polluted and aquifers are depleted and degraded; (3) Excessive use of water by industry and agriculture and unsustainable consumption patterns put a sever strain on limited water resources; (4) New distant water sources are being sought and tapped at enormous cost to cater for rising demand; (5) At the same time, huge amounts of treated, potable water are wasted through leakages in distributions systems that are often old and seldom well maintained; (6) Water is delivered at a subsidized price to the middle and upper classes, while the under-served majority has an erratic, unreliable supply or depends on informal channels such as water vendors, at a much higher unit cost; (7) For a variety of reasons, many water and sanitation utilities are unable to operate and maintain existing infrastructure, to manage demand, recover service costs or make the investments that would be necessary to extend services; (8) Institutional responsibilities for water resources management are fragmented, and there is very little dialogue among the various institutions concerned.