Regulatory library
A library of our most recent and historic documents, including our Annual Performance Report (APR), Scheme of Charges and Licence Conditions.
Our latest 2024 reports
Read our 2024 Annual Performance Report and Methodology Statement.
AMP 7
AMP 6
Regulatory Accounts
AMP 7
AMP 6
This data is licensed under CC BY, an open data licence, in order to make it freely available to other potential customers, stakeholders or interested organisations.
What is Event Duration Monitoring?
Storm overflows are vital in protecting people from flooding and are widely used across the UK and Europe. We fully understand the concern around them and the impact they can have on rivers. We use monitors on our storm overflows to understand the performance of our sites and undertake required action. This is called Event Duration Monitoring (EDM).
Our monitors take readings of the water level either every two minutes or every 15 minutes depending on the classification of the receiving watercourse, which is jointly agreed between Hafren Dyfrdwy and the Environment Agency.
Every data point captured at or above the overflow level would count towards the total time that a discharge was occurring at that location.
Our Q1 2025 Event Duration Monitoring data
We’ve published our Event Duration Monitoring (EDM) data for Q1 2025. This data contains all the monitoring activity at storm overflows across the Hafren Dyfrdwy region.
As part of our Get River Positive pledges, we have committed to ensuring we are open and transparent and provide information such as this, on our website and in an easily accessible way. We already publish our data annually, and we are now we are committing to further openness by publishing our EDM data quarterly at first, before moving to reporting it monthly by Autumn 2025.
Importantly, our quarterly and monthly data will be raw and unassured. However, we are dedicated to making our data available promptly, ensuring timely access without waiting a whole year.
Our data is showing a performance of 6 spills on average for the first quarter (January – March) of 2025.
At Hafren Dyfrdwy, we are dedicated to continually enhancing our data accuracy. However, there may be instances where our sensitive monitors provide incorrect readings. We seek to actively address such issues and constantly strive to improve the quality of our data. As a result, the data may be updated before our annual submission, following a rigorous assurance process
AMP 7
AMP 6
The original information contained in this document is updated annually and reflected in the Annual Performance Report, offering a comprehensive overview of how the organisation upholds transparency, ensures accuracy and accountability, and maintains compliance with regulatory expectations.
To request a copy of a report in Welsh, please email compliance.assurance@severntrent.co.uk
Household
Wholesale non-household
Non-household
Household
Non - household
Our charges are subject to a formal system of price regulations and control, monitored and enforced by the Water Services Regulation Authority – better known as Ofwat.
Every five years Ofwat carries out a ‘Periodic Review’ of our costs, charges and future investment requirements. Having considered our performance and efficiency in providing services (relative to the other companies in England and Wales), they set a series of annual price limits for each service for the 5 years covered by the review. This determines how much revenue we are allowed to recover every year from each service. In addition, they set out a series of performance measures that we are required to meet. These performance measures, referred to as ‘Output Delivery Incentives’ or more often ‘ODI’s’, reflect customers priorities e.g., reductions in leakage, sewer flooding etc. and can attract financial rewards and penalties – outperforming against an ODI and providing a higher level of service to customers can generate a financial reward, whilst underperforming can give rise to a financial penalty.
We have been allowed funding of £266 million over the 5-year period – up from £199 million in 2020-25. This significant increase recognises a step-change in the Water Industry National
Environment Programme (WINEP), expenditure on the water supply-demand balance, water quality, increased resilience, improved asset health, investment to facilitate population growth and new houses and improved services to customers. Further details of this overall investment and the performance measures that we have agreed to deliver over the next five years can be found below.
The annual revenue controls set by Ofwat (see below) allow us to recover a fixed amount of revenue from our customers. For most of our charges these are then modified by inflation, adjustments for performance and any over or under-recovery in previous years.
The annual increases set out in Ofwat’s Final Determination i.e. before any of the above adjustments are as follows:
2025-26 % |
2026-27 % |
2027-28 % |
2028-29 % |
2029-30 % |
|
| Water Resources activities | 175.52 | 9.36 | 5.36 | -4.65 | -3.60 |
| Network Plus water activities | 21.99 | 9.01 | 3.99 | -9.09 | 5.07 |
| Network plus wastewater activities | 65.19 | 7.95 | 5.92 | 6.90 | 3.72 |
2025-26 % |
2026-27 % |
2027-28 % |
2028-29 % |
2029-30 % |
|
| Bioresources unadjusted revenue | 0.670 | 0.675 | 0.683 | 0.689 | 0.695 |
The above price controls and increases are to fund our investment programme which covers four areas:
To mitigate the impact of the increases referred to above, customers may want to consider whether they can reduce their water usage. Information on water efficiency can be found on our website by following the links below: