Quality control of wastewater for irrigated crop production. (Water reports - 10)

Table of Contents

D.W. Westcot
Environmental Program Manager
California Regional Water Quality Control Board
Sacramento, California, USA

Rome, 1997

ISSN 1020-1203

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ISBN 92-5-103994-1

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© FAO 1997

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Table of Contents



Chapter 1 - Introduction

Chapter 2 - Health risks associated with wastewater use

Types of pathogens present in wastewater
Pathogens that reach the field or crop
Pathogen survival under agricultural field conditions
Relative health risk from wastewater use
Agronomic conditions that minimize disease spread when wastewater is used for irrigation
Guidelines for public health protection during wastewater use

Chapter 3 - Implementing health protection measures for wastewater use

Wastewater treatment to lower health risks
Lowering risk of direct human exposure in areas using wastewater
Lowering risk to consumers through crop restrictions

Chapter 4 - Developing a programme to promote safe production

Phase I: Development of a sound information base

Selection of study areas to determine safe production zones
Parameters used for measurement of microbial contamination
Analytical methods which can give acceptable results
Laboratory selection
Field sampling techniques
Criteria used to select field monitoring sites

Phase II: Organization and analysis of the information

Historical sources of data
Sampling frequency and criteria used to evaluate the data
Database, mapping systems

Phase III: Certification programmes and institutional and policy issues

Certification programmes

Policy considerations for certification
Developing a water quality certification programme

Institutional and policy issues

Water certification
Policy issues for development of safe production areas

Chapter 5 - The case study of Chile

Planning for controlling the quality of irrigation water destined for vegetable production in Chile