Safe and productive use of wastewater in agriculture

Safe and productive use of wastewater in agriculture Javier Mateo-Sagasta Dávila FAO Land Water Division

INDEX • Clarifying concepts • Why wastewater is used? • How to manage risks? • Treatment • Non-treatment options • Capacity needs

Municipal wastewater

Types of Re. Use Direct Use

Types of Re. Use Indirect Use

Types of Re. Use Direct or Indirect use of: • Untreated wastewater • Partially treated wastewater • Reclaimed water

Types of Re. Use Direct or Indirect use of: • Untreated wastewater • Partially treated wastewater In developing or emerging coutries

Why wastewater is used Water Scarcity

Why wastewater is used Water Pollution

Why wastewater is used These two drivers are specially important in urban and periurban Water Scarcity areas Fierce competition Water Pollution for clean water

Why wastewater is used Consequence: Millions of farmers, specially in peri-urban areas, have no option but to use marginal quality water to irrigate their crops.

Why wastewater is used Nutrients Macro nutrients (N and P), Micro nutrients (K, Ca, Mg…) Organic matter – Demand of chemical fertilizers is reduced – it may be the only source of fertilizers for poor farmers

Why wastewater is used Available all year round Monday Unlike rain water or natural water courses. It allows: • More types of crops Tuesday Springtime • More corps per year • Higher incomes Summer

Opportunities Agriculture • Water all year round • Nutrients and organic matter • Higher yields • Closer to cities • More crops/year • Higher incomes Cities • Food security • Cheap wastewater treatment • Freshwater conervation Environment • Lower pollution • Freshwater conservation

Risks Hazards in wastewater Parasitic Protozoa Helmints Ameba intestinalis Ascaris Virus Enteric Virus Bacteria Cholera, typhus, salmonella Heavey Metals Giardia Intestinalis Others

Risks Hazards in wastewater Can Harm: • Environment • Human health

Risks Groups at risk • • • Consumers Farmers and their families Close communities

Risk management OPTION 1: Eliminate hazards: Safe Water Reclamation OPTION 2: Risk management: Multiple barriers Lower the hazard and reduce the exposure

Risk management OPTION 1: Eliminate hazards: Safe Water • Common in high income countries • Strict water quality standards for reuse • Advanced Wastewater Treatment = water reclamation

Risk management Plantas de tratamientos de aguas Wastewater Treatment residuales en Plants Ghana

Risk management How many are really Cuantas working? funcionan?

Risk management Some times don’t work

Risk management Why they don’t work? Not operated and poorly maintained • Frequent power cuts • Lack of technical capacities • No capacity to pay

Risk management OPTION 2: Risk management: Multiple barriers Lower the hazard and reduce the exposure Types of barriers:

Risk management Guidelines PROCEDURE • Risk assessment • Health based targets • Health protection options • Treatment • Other barriers • Monitoring

Capacity development productive To promote a more wastewater in agriculture… Countries need to and safer use of develop their capacities. System Políticas, estrategias, leyes y normativa, colaboración entre partes interesadas… Organization Resources (human, financial…), proceduress, structures, infrastructures… Individual Kowledge and skills

Capacity development We can support this process

Capacity development We can support this process

THANK YOU!