Regulatory Library

Regulatory library

A library of our most recent documents as well as the historic Dee Valley Water documents.

As Hafren Dyfrdwy was formed in the middle of the five year period, you will find documents here for Dee Valley Water, Severn Trent and Hafren Dyfrdwy. 

Our latest 2023 reports

Read our 2023 Annual Performance Report and Methodology Statement.

Regulatory Reporting

Statutory Accounting

Event Duration Monitor (EDM) Data

You can find our Event Duration Monitor (EDM) report here.

Each line covers a single storm overflow showing spill frequency, duration of spill and percentage of reporting period the EDM was operational.

Comments have been added to highlight key information regarding the data supplied.

The period of reporting starts from the 1st April 2020 to align with the updated Natural Resources Wales permits.


Regulatory Compliance and Assurance

Licence Conditions

Scheme of Charges

Other significant documents

PR14 reconciliation documents

Consultation Responses