Use of wastewater in agriculture
Population growth and rapid urbanization are intensifying pressure on fresh water resources. The lack of quality water and a high level of local water demand is leading to increasing water scarcity and stress and is consequently driving the use of non-conventional waters, such us treated or raw wastewater.
Wastewater use for irrigated agriculture is especially important in urban and periurban areas. Cities are in fact a precious source of water and nutrients for agriculture that have to be properly managed to minimize environmental and health risks. To maximize benefits and minimize risks related to the use of wastewater in irrigation a robust policy and institutional framework needs to be in place. In many countries where wastewater use in agriculture takes place these frameworks are lacking. Responsibilities and jurisdictions among public institutions (health, agriculture, water) have to be clear and coordination mechanisms should be created to come up with comprehensive and effective policies.
Cost effective and appropriate wastewater treatment suited for the end use of wastewater is a fundamental action. But in many developing countries wastewater treatment is not economically feasible in the short term and interim solutions may be needed to protect farmers and public health In these countries the focus should be on prioritizing affordable and easily adoptable risk management strategies. Adopting the multiple-barrier approach (WHO-FAO-UNEP, 2006) can reduce human and crop exposure to toxic compounds and pathogens.
Farmers need to be provided with the specific guidelines to support their productions and to access markets, and proper dissemination and education campaigns need to be designed to facilitate the adoption of such guidelines by farmers. Additionally, policy makers and consumers need to understand the opportunities of water reuse and resource recovery from waste.