ZDHC Announces New Wastewater Guidelines

Environmentally conscious organizations are strengthening their criteria as the demand for more sustainable output grows. The Zero Discharge of Hazardous Chemicals (ZDHC), a chemical management organization, released updated guidelines for the textile, leather, and footwear industries regarding industrial wastewater and sludge earlier this week.

The ZDHC Wastewater Guidelines were initially published in 2016 to describe a consistent set of worldwide wastewater quality objectives for the apparel, textile, and footwear industries. The update reinforces the evolution of its Roadmap to Zero Program, which began in 2011 with six signatory companies to improve the global fashion supply chain. The initiative now has over 160 contributing partners, including labels such as H&M, Gap, Inc., and G-Star Raw, as well as mills such as Isko, Soorty, Elevate Textiles, and Candiani.

The ZDHC Wastewater Guidelines Version 2.0 incorporates previously separate textile and leather wastewater guidelines, as well as a streamlined approach to sampling and testing for direct, indirect, and zero liquid discharge, the ZDHC Manufacturing Restricted Substance List (ZDHC MRSL) Version 2.0, guidance on appropriate sludge disposal pathways, and an update on sludge testing parameters.

The ZDHC’s Wastewater Council, a panel of independent wastewater specialists from the textile industry, academia, and the water treatment industry, decided on the updates. The revision also includes the ZDHC Sludge Reference Document Version 1.0, which provides a methodology for facilities to determine sludge disposal pathways, and the ZDHC Wastewater and Sludge Laboratory Sampling and Analysis Plan Version 2.0, which provides a detailed framework for laboratories to test and determine the concentration of parameters in wastewater and sludge.

Key updates

• The ZDHC Wastewater Guidelines Version 2.0 combines previously separate textile- and leather wastewater guidelines into one 
• The guidelines introduce a streamlined approach to sampling and testing for Direct, Indirect and Zero Liquid Discharge
• Incorporation of the ZDHC Manufacturing Restricted Substance List (ZDHC MRSL) Version 2.0
• Guidance on appropriate sludge disposal pathways and an update on sludge testing parameters

The recommendations come at a time when the sector is becoming increasingly concerned about its environmental impact. Water Witness International (WWI), a U.K.-based organization dedicated to sustainable water resource management, discovered excessive water contamination in some African countries that contribute to the global fashion supply chain in August. Waterways in top sourcing countries like Ethiopia, Lesotho, Madagascar, Mauritius, and Tanzania have a pH of 12 (the same as home bleach) and high quantities of carcinogenic chemicals. Water was obviously polluted with blue dye from denim manufacture in neighboring places. Polluted runoff endangers the health of local residents and crops watered with the water, and contact with the pollution causes skin burns and sickness.