The disposal of liquid animal wastes pollutes surface and groundwater and is the main environmental problem in some intensively farmed regions. Conversely, natural resources sectors such as agriculture, forestry and nature conservation can hold the key to improving the management of water resources. Certain kinds of farm practices, such as terracing and agroforestry, can help to preserve and improve the functions of watersheds and catchment areas. Afforestation, and sustainable management of standing forests, also has a vital part to play in the protection of upland water sources. Thus more careful use of water by irrigators can release supplies for the use of growing cities, or for hydropower or environmental purposes, while more diligent use of agrochemicals and better drainage practices would improve the quality of water for downstream users.
Water has an international dimension where countries share a river, lake, coast or aquifer.
The issues are similar to those arising where the resource is of purely national concern, except that sovereignty is involved, international law is applicable, aid is often at stake, and countries may be willing to go to war to defend their interests. There is a serious risk of water becoming a casus belli in some of the arid parts of the world. The international debate Water issues have been the subject of increasing international concern and debate. The ICWE called for innovative approaches to the assessment, development and management of freshwater resources. In 1993, the World Bank issued a comprehensive policy paper defining its new objectives for the water sector.