ISO 16075-2:2020

Overview

ISO 16075-2:2020 - "Guidelines for treated wastewater use for irrigation projects - Part 2: Development of the project" provides practical guidance for designing and implementing irrigation projects that use treated wastewater (TWW). The standard focuses on preventing public health risks for populations in direct or indirect contact with TWW or products irrigated with TWW. It is part of the ISO 16075 series on water reuse and is intended as a design and planning guideline, not for certification.

Key topics and technical requirements

• TWW quality characterization: Defines TWW classes based on chemical, physical and biological parameters (e.g., BOD, TSS, turbidity, indicator bacteria and nematodes) and links quality levels to potential uses.
• Fit‑for‑purpose approach: Emphasizes matching reclaimed water quality and treatment level to the intended irrigation use (agricultural, urban/landscape, gardens).
• Integration of crops and water quality: Provides guidance on crop categories and how crop sensitivity affects allowable TWW quality and management measures.
• Barriers and risk reduction: Specifies types of operational and physical barriers (application controls, crop restrictions, buffer zones, treatment steps) and how barriers should be combined with TWW quality to reduce health risks.
• Distribution, irrigation method and public health: Addresses risks from irrigation techniques (including flood and furrow irrigation), timing, equipment, signage, and preventing contamination of drinking water systems.
• Treated greywater (TGW): Includes Clause 7 on garden irrigation with treated greywater, covering quality maintenance, irrigation timing, equipment and signage.
• Site planning considerations: Includes guidance on distances between TWW irrigated areas and residential zones, monitoring, operation, maintenance and preventing groundwater/surface water contamination.
• Annexes and updates: Annex A helps adjust TWW quality and barriers to crop types; the 2020 edition updates turbidity values, public garden irrigation guidance and adds a column on washing/disinfection of produce.

Practical applications

Who uses ISO 16075-2:2020:

• Water reuse and wastewater treatment engineers designing TWW supply and treatment trains.
• Irrigation planners, agronomists and landscape architects specifying crop choices and irrigation methods.
• Municipal authorities and public health agencies developing local reuse policies and risk management.
• Consultants and project managers implementing urban and agricultural water reuse projects.
  Practical benefits include reducing public health risks, optimizing treatment costs via fit‑for‑purpose reuse, protecting soil and crops from salinity/heavy‑metal impacts, and ensuring compatible irrigation system design and monitoring.

Related standards

• ISO 16075-1:2020 - Guidelines for treated wastewater use for irrigation projects - Part 1: The basis of a reuse project for irrigation.
• ISO 20670:2018 - Water reuse - Vocabulary.

Keywords: ISO 16075-2:2020, treated wastewater (TWW), water reuse, TWW irrigation, treated greywater, public health protection, irrigation project design, fit‑for‑purpose.