Evolving Urban Health Risks in Low- and Middle- Income Countries: From Housing, Water and Sanitation to Cities and Climate Change

ion, and the like. The science of climate change and its impacts is very uncertain, though this does not distinguish it from the science of water and sanitation. A more obvious distinction is that whereas progress on water and sanitation is often inhibited by a tendency to turn to outdated models of improvement, progress on adaptation to climate change is inhibited by the lack of models to turn to. Warming itself can have a direct impact on health, and the net impact is likely to be negative. Sea-level rise and storm surges are likely have a major impact on health, particularly in unprepared urban areas. Declining water resources may also have a direct impact on health, unless ways are found to secure the basic requirements of deprived urban dwellers in the face of competition from other users. There are also many more indirect ways in which climate change could affect urban health adversely, ranging from changes in the transmission and evolution of infectious diseases, to declining food supplies, to global economic crises. While the challenges of urban housing, water and sanitation are clearly very different from those of cities and climate change, there are also important similarities, particularly when it comes to health vulnerabilities and the need for action. The urban groups most vulnerable to the health impacts of climate change are likely to be within the deprived urban populations that currently suffer from environmental health risks due to inadequate housing, water and sanitation. This reflects a broader generality; the urban populations most vulnerable to global environmental pressures are likely to be among the populations that already face the greatest health risks as the result of local environmental burdens. Alternatively, even in lowand middleincome countries, settlements that have managed to address their local environmental challenges efficiently and equitably are likely to be in a better position to adapt to the challenges of global environmental change. Thus, urban settlements that have already addressed the water and sanitation challenges of their most vulnerable populations are likely to be in the best position to cope with increasing water scarcity efficiently and equitably. Similarly, urban settlements that have already addressed the land and housing challenges of their most vulnerable populations are likely to be in the best position to cope with increasing flood risks efficiently and equitably. This clearly has implications for urban planning, the last theme of this summit. Some of these planning implications are considered in the course of this paper, but most are left open for discussion. Similarly, the research implications are left for discussion. DRAFT, NOT TO BE CITED 2 Improving Urban Population Health Systems CENTER FOR SUSTAINABLE URBAN DEVELOPMENT | JULY 15-20, 2007 Table of