1. Wastewater (including greywater) treatment and non-treatment options for use in agriculture
Dr. Satya Priya for
Javier Mateo-Sagasta Dávila
FAO Land and Water Division

2. Global figures on wastewater use in agriculture
INDEX
Global figures on wastewater use in agriculture
Why wastewater is used?
How to manage risks?
Treatment
Non-treatment options

3. May be underreported! 50 Countries 5-20 million hectares
Global figures
Use of untreated or partially treated WW
50 Countries
5-20 million hectares
Difficult to monitor by public authorities.
May be underreported!

4. Why wastewater is used
Water Scarcity

5. Why wastewater is used
Water Pollution

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

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

8. 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

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

10. Opportunities of water reuse
Why wastewater is used
Opportunities of water reuse
Linear society:
Pollution and lost resources
Recycling society:
Improved food security

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

12. Can Harm: Environment Crop productivity Human health Risks
Hazards in wastewater
Can Harm:
Environment
Crop productivity
Human health

13. Risks Groups at risk Consumers Farmers and their families
Close communities

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

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

16. Risk management
Some times don’t work

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

18. Types of barriers: Risk management OPTION 2: Risk management:
Multiple barriers
Lower the hazard and reduce the exposure
Types of barriers:
Treatment (low cost)
Crop restriction
Irrigation techniques
Produce washing or cooking

19. Greywater Treatment System
Risk management
Example of a Low-cost treatment:
Greywater Treatment System
Green removal panel
Manhole- steel cover
Screen Filter
To the irrigation system
Stone
Vales

20. Capacity development
To promote the productive and safe use of wastewater in agriculture…
Countries need to develop their capacities.
Contaminants in Wastewater can harm health and the environment

21. We can support you in this process.
Capacity development
We can support you in this process.

22. THANK YOU! 22