Report results using ZDHC Gateway Wastewater Module

Version 1 - Last updated 01 Jul 2026

Only ZDHC Approved Wastewater and Sludge Laboratories are authorised to submit wastewater and sludge test reports to the ZDHC Gateway on behalf of suppliers. Laboratories should ensure that all reported data complies with applicable ZDHC technical and quality requirements prior to submission. Accurate and complete data upload enables the generation of the supplier’s ClearStream Report and ensures transparency and integrity.

Reporting means submitting test data/results to the ZDHC Gateway Wastewater Module. The integrity of the test data in the ZDHC Gateway must be at its highest possible standard. This will support the ZDHC Roadmap to Zero Programme in making scientific and data-driven decisions necessary to shape the future of our industry.

1. All ZDHC Approved Wastewater Laboratories are expected to follow the data reporting requirements in this section.

2. All test data must be reported using the EDR template generated in the ZDHC Gateway.

3. The use of reporting formats other than those approved in the EDR will not be accepted.

4. The following data qualifiers can be used when a numerical value is not entered for a parameter:

“Insufficient sample” - not enough sample volume was provided.
“QA/QC” - sample analysis did not meet ZDHC data quality objectives

What is ZDHC Gateway?

The ZDHC Gateway is the go-to platform ZDHC has developed for the fashion and textile industry to support the implementation of our roadmap to zero programme. Gateway is the world's largest database of sustainable chemical products and the community tool for the entire fashion and textile industry.

The ZDHC Gateway is open to ZDHC Signatories, Friends of ZDHC and their supply chains.

Learn more about getting started on the Gateway

There are two modules within the ZDHC Gateway:

Chemical Module:

A world-renowned database of safer chemistry for the textile, apparel, leather and footwear industry.

Wastewater Module:

A global online platform that enables users to register and share verified wastewater test data against the ZDHC Wastewater and Sludge Guidelines, and to generate ClearStream Reports.

Standard framework for reporting wastewater and sludge test results on the ZDHC Gateway

The ZDHC Gateway Electronic Data Reporting System is based on a standardised data template, in which the data rules have been set.

1. Define the suppliers' discharge types and sample locations.

By completing the ZDHC Gateway Supplier Profile.

2. Drawing from the data from the Laboratory Information Management System (LIMS).

The ZDHC Approved Wastewater and Sludge Laboratories are expected to populate test results and related data onto the ZDHC Gateway Electronic Reporting Template with a complete dataset. This means every single parameter/analyte must be reported, unless indicated otherwise within this document or within the latest version of the ZDHC Wastewater and Sludge Guidelines. In the event that a parameter/analyte was not analysed, then a reason must be provided. The possible options are listed within EDR Data Entry Requirements, column: 'Result Text.

3. Upload data onto the ZDHC Gateway.

When the ZDHC Approved Wastewater and Sludge Laboratory is ready to upload the data onto the ZDHC Gateway, the ZDHC Approved Wastewater and Sludge Laboratories should drag and drop the completed Electronic Reporting Template onto the ZDHC Gateway.

4. ZDHC Gateway will conduct an automated data validation.

Only the entire fully data rules-compliant dataset is accepted

5. In case the system detects issues with specific data points.

The ZDHC Gateway will reject the entire dataset and point out which data point(s) need to be rectified. The Approved Wastewater and Sludge Laboratories must re-upload the entire dataset after these data points have been fixed. After the dataset is uploaded, another round of automated data validation will be processed before any acceptance of data. This process will repeat until all data on the Electronic Data Reporting Template is compliant with the validation rules described in EDR Data Entry Requirements.

6. After successfully submitting the dataset, suppliers can then generate the ZDHC ClearStream Report and review the information and the results.

Suppliers have 20 business days from the date that the lab uploads results to accept and publish results or to decline lab results.. If no action is taken by the supplier to accept or decline results following the after 20 days period, the system will automatically accept the results. Publication of the test data on the ZDHC Gateway will be done in accordance with the latest version of the ZDHC Gateway Terms and Conditions.

7. All required testing must be completed and reported within a maximum of 45 calendar days from the cycle end.

This requirement is mandatory for all laboratories.

The Electronic Data Reporting System uses a drag-and-drop interface within the ZDHC Gateway, providing ZDHC Approved Wastewater and Sludge Laboratories with streamlined in-app submission and automated validation feedback.

Data must be submitted in Excel Macro (.xlm) format and not exceed 10MB. If data integrity issues or rule non-compliances are detected, the system will automatically reject the entire dataset. Laboratories must correct all errors before resubmission and may choose to upload reports individually to ensure accuracy.

Critical guidance on how to carry out EDR reporting correctly

The Electronic Data Reporting requirements define the necessary data, formats, and mandatory fields for submissions in the ZDHC Gateway, ensuring that wastewater reporting is accurate, consistent, and accepted by the system.

Temperature difference

If the temperature difference cannot be reported due to risks in sampling, this should be specified in the Custom EDR Builder. If this is specified, then the EDR file will be auto-populated with “NA-risk”. This is the only value that should be used for temperature difference within the column, Result Text, if a numeric value cannot be reported.

Water Flow rate

If the wastewater flow rate cannot be reported due to risks in sampling, this should be specified in the Custom EDR Builder. If this is specified, then the EDR file will be auto-populated with “NA-risk”. This is the only value that should be used for wastewater flow rate within the column, Result Text, if a numeric value cannot be reported.

Persistent foam

When reporting persistent foam, the only acceptable values are either “absent” or “present”.

Colour

The colour parameter is divided into three separate parameters, by colour wavelengths. The colour parameters are:

Colour 436nm
Colour 525nm
Colour 620nm

All colour parameters will be reported using the unit of measure m-1.

Paint filter test

When reporting paint filter test the only acceptable values are either “pass” or “fail”.

Additional Instructions for Not-Analysed and Non-Detected Instructions:

Not-Analysed ("NA")

Is not accepted for the following parameters: pH, temperature difference.

Non-Detected ("ND")

Is not accepted for the following parameters: pH, temperature difference, persistent foam and wastewater flow rate.

EDR Parameter Codes and Unit of Measure

All parameter codes are summarised in the EDR Parameter Codes and Unit of Measure (UOM) table.

Some ZDHC parameters have multiple CAS No. or identifiers. If the specific CAS No. is not on the parameter list, a solution provider may use the generic name.

Example

For the ZDHC Parameter MONO-, DI- AND TRI-BUTYLTIN DERIVATIVES, a solution provider may report under the CAS No. 0818-08- 06 or the generic name 'BUTYLTIN'

Learn more about navigating and advanced aspects of the ZDHC Gateway, including how to activate a supplier or how to upload a test report, in this Knowledge Base article.