The degradation of watersheds has led to flooding becoming more frequent and more severe, and pollution of ground water is resulting in health risks, increases in cost of infrastructure and reduced agricultural productivity. Topsoil loss in the watershed areas is simultaneously reducing agricultural productivity and increasing siltation of stream channels and damaging offshore reefs. In Jamaica, as with other small island developing states, there is an extremely close relationship between the terrestrial and marine ecosystems. Land degradation in the hills is quickly manifested in impacts on marine resources and particularly in damage to coral reef and related ecosystems. In addition, the varied and mountainous inland terrain supports a number of ecosystems unusually rich in biodiversity.
Water is the link that ties the terrestrial ecosystems with marine habitats and lowland urban areas.
The human settlements of the lowland urban areas and unplanned hillside communities are another important aspect of Jamaica's environment. The unavailability of land for low-income settlements has led to overcrowded squatter settlements, short of domestic water and sewage facilities and plagued with public health risks and the other social and economic problems of urban settlements. The urban management and settlement issues are not confined to those of the informal sector, but are compounded by poor adherence to physical planning precepts which has led to the juxtaposition of industries and residential areas. There is a particular concern in relation to the agroprocessing sector which has traditionally disposed of its waste in streams and sinkholes, and whose impacts on the water resources are significant. People are at the centre of the environment in Jamaica.