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To understand the scale of improvement needed we need to assess the capacity of the drainage and sewerage networks over the long term.

To do this a Drainage and Wastewater Management Plan (DWMP) has been developed and will be consulted on by water companies with customers, stakeholders, regulators, and local authorities.

The DWMP will be comprehensive, evidence based and transparent in assessing, as far as possible, current capacity and actions needed in a 5year, 10 year and 25-year periods considering risks and issues such as climate change.  It will align, as far as possible, with other strategic and policy planning tools.  It will aim to deliver resilient drainage and sewerage networks that meet operational and other pressures and minimise system failures.  

In developing the plan the impact of drainage systems on the immediate and wider environmental outcomes including habitats will be considered and in developing solutions, options for environmental net gain and enhancement will be included.

The DWMP will be collaborative and recognise the importance of sectors working together to respond to current and future risks to water quality and customer service as well as the need to deliver effective solutions, setting out how they will do this, and how stakeholders have been engaged and responded to. The plan will improve customer outcomes and awareness of the solutions needed to protect the environment as well as understand that the actions will provide both value for money and benefits to society as a whole.

The plan should show leadership in considering each organisation’s operational capacity to develop and deliver the plan and be mindful of linkages with other strategic planning frameworks.  Finally the plan will be developed in line with the behaviours set out in the Wellbeing of Future Generations Act 2015 and explain how they will contribute towards the wellbeing outcomes. DWMPs will also help water companies and their stakeholders deliver their obligations under the Environment (Wales) Act 2016.

The outcome of the DWMP will be a plan that, subject to the consultation response, will put storm overflows in the areas served by Dwr Cymru and Hafren Dyfrdwy on a path to improved understanding of their impact with the aim of eliminating ecological harm to the environment.  

Short term outcomes will focus on better understanding, decision support tools and development of an adaptive pathway to show how the plan may need to change over time in response to the challenges of growth, climate change and urban creep and changes in regulation.  The plan will, subject to the consultation responses from stakeholders and customers, include investment proposals for reducing storm overflow spills in AMP8, establish the timescales over which reductions to storm overflow discharges, along with reducing the risk of flooding, should be delivered and indicate areas where other Risk Management Authorities are critical to the delivery of these outcomes. 

Our commitments

The actions being taken forward within this workstream are all aligned to the Welsh Government Programme for Government 2021-26 and the Wellbeing goals of:

  • Building a stronger, greener economy as we make maximum progress towards decarbonisation.
  • Make our cities, towns and villages even better places in which to live and work.
  • Embed our response to the climate and nature emergency in everything we do.
  • Begin to designate Wales’ inland waters for recreation, strengthening water quality monitoring.
Lead Organisation    Action     Why?     By When
Dwr Cymru and Hafren Dyfrdwy      Consult on the draft DWMP, prepare a revised draft plan and statement of response to the consultation.   To gather views from customers and stakeholders on the draft DWMP and reflect these in the final draft plan.     The revised draft plan is expected to be published by end of December 2022
Welsh Government     Instruct water companies to publish their DWMPs.     To confirm that the plans have been formally adopted and that water companies should begin reporting on progress.   Spring 2023
Dwr Cymru and Hafren Dyfrdwy     Commence DWMP cycle 2.      To begin the process of updating the DWMP and expanding its scope and accuracy.  This will allow water companies to improve their understanding of storm overflows impact on the environment and enable them to develop wider scale investment plans for inclusion in AMP9 and beyond.  This will have the aim of eliminating ecological harm from storm overflows in as soon as possible and making those improvements resilient to pressures such as climate change.    Spring 2023 with a view to publishing the second draft plan in 2027
Dwr Cymru and Hafren Dyfrdwy   Incorporate storm overflow improvements identified in the DWMP into PR24 draft business plans for investment in AMP8   To provide investment funding to make storm overflows improvements in AMP8 business plans.   September 2023
Dwr Cymru and Hafren Dyfrdwy   DWMP communication   To provide a set of clear messages about the DWMP (what it is and aims to do) to the Comms workstream.  Explain the links to, and role of, the business planning process, prioritisation of investment and the potential impact on customer affordability.   To coincide with the consultation and publication timelines.
Welsh Government   Develop regulatory guidance for the DWMP   In order to develop the legislative requirements for the DWMP including the duties of roles of Water Companies, Regulators and Local Authorities in order to make the DWMP a statutory requirement for water companies.   Spring 2023
Welsh Government   Drainage management review     So that the need for a new management structure for sewerage and drainage in Wales can be reviewed and provide proposals that will facilitate coordinated and joined-up investment between drainage and sewerage operators in Wales.  This will include the need for water companies, NRW and LAs to share asset information and develop their areas of common interest.   From Spring 2023 onwards
Natural Resources Wales and Local Authorities     Engagement with the DWMP     NRW and LAs engage with the DWMP as both drainage operators and regulators so that collaborative plans are developed for protecting river water quality at the same time as reducing flood risk     From the publication of the draft DWMP for consultation
Dwr Cymru and Hafren Dyfrdwy     Adopting best practice   In order to identify good practice measures in England and Scotland that can be adopted in Wales and plan for introduction throughout cycle 2 of the DWMP.     Spring 2023 onwards
Dwr Cymru and Hafren Dyfrdwy     Storm overflow evidence project   In order to support the goals for the Storm Overflows Evidence Project for Wales and provide the required information if available.     To be confirmed