Postponement of the ZDHC WWG V3.0 and publication of the ZDHC WWG V2.2

Scope of update

The ZDHC Wastewater Guidelines (WWG) is currently being updated from the V2.1 to V3.0, in close coordination of the ZDHC Water Competence Centre with the Wastewater Council. 

The scope of this update is:

1. To include the ZDHC MRSL V3.1 new substances for their reporting limits and test methods to evaluate their presence in the raw wastewater.
2. Review the conventional parameters, anions and metals for any necessary changes in limit values and test methods, as well as alignment between textile and leather requirements.
3. Review the sludge testing, documentation requirements and disposal pathways (as outlined in the Sludge Reference Document)
4. Add applicable new ZDHC MRSL V3.1 substances for testing in sludge for confirmation of the disposal pathways.
5. Work on the topics listed in the Candidate List of the Wastewater Guidelines V2.1:

• Microfibres/fibre fragments discharge in wastewater
• Water use targets
• Check for effluent toxicity
• Smart, intelligent testing to target risks and eliminate test redundancy  

While a majority of the above topics are completed, there are some which are in progress.

‍Postponement of V3.0 and next steps

ZDHC would like to update and publish the Wastewater Guidelines V3.0 that covers all the above mentioned aspects. Putting all these topics together will require more time and therefore we have decided to postpone the publication of the Wastewater Guidelines V3.0 to the end of 2024. The implementation of the V3.0 will be in 2025 and will also combine a new approach to implementation in line with the ZDHC 2030 Impact Strategy.

While postponing the release of the Wastewater Guidelines V3.0, we realise that there are some issues in the current ZDHC Wastewater Guidelines V2.1 that need to be addressed or clarified for implementation. The sludge testing and disposal pathways process also needs to be simplified. The study conducted by the Microfibres Task Team has positively established a correlation between Total Suspended Solids (TSS) and quantity of microfibre release in wastewater and this outcome of TSS as an indicator of microfibre release also needs to be communicated.

Thus, we propose to publish a ZDHC Wastewater Guidelines V2.2  to cover the above clarifications and topics. This V2.2 will also include improved alignment between textile and leather wastewater testing requirements.

The ZDHC Wastewater Guidelines V2.2 will be published in September 2024, and implementation of this version will be from the testing cycle beginning from November 2024. The Wastewater Guidelines V2.2 will not require re-approval of the currently ZDHC Approved Wastewater Labs nor would any new test parameters be introduced in the version. 

The draft of the ZDHC Wastewater Guidelines V2.2 will be sent for Signatory review prior to its publication and implementation. After the publication, the ZDHC Water Competence Centre will conduct webinars for all stakeholders (including the wastewater laboratories) to explain the changes in the WWG V2.2, publish relevant Knowledge Base articles and incorporate any likely impacts on the Sampling & Analysis Plan (SAP) document for a detailed understanding by the ZDHC Approved Wastewater Labs.

‍ZDHC 2030 Impact Strategy and proposal to review current testing protocol

In the ZDHC Impact Strategy 2030, under the MRSL SCM framework excellence, one of the strategies is to drive the use of better input chemistry with more emphasis on monitoring chemical use at factories rather than end-of-pipe testing, by using appropriate data. While the current practice of bi-annual wastewater testing cycles is effective in identifying hazardous substances, it does not provide real-time impact measurements on water quality or biodiversity. The frequency of testing also does not provide an assurance that ZDHC MRSL substances have been phased out or conventional parameters are met consistently.

This would necessitate a review of the current wastewater testing protocol and a transition to a dynamic and pragmatic approach that incentivises input chemical management including ZDHC MRSL conformance of chemical inputs (InCheck), and is based on product and process-specific risks (smart testing grid), performance test history (ClearStream Reports) and efficiency of ETP performance (ETP Efficiency Evaluation Protocol). We will thus link the publication of the ZDHC WWG 3.0 to a new Implementation Plan for wastewater and sludge management.