New appointments and variations (NAVs)

The Water Industry Act 1991 incorporates legislation which makes provision for sites within an existing undertaker’s area to be served by another undertaker. Where an alternative undertaker is appointed, a NAV is made by Ofwat.

There are three circumstances in which a NAV can be granted:

  • Where the premises of one or more customers is supplied (or is likely to be supplied) with at least 50 megalitres of water per year. The same criterion applies for water recycling services;
  • Where no premises within the area are served by an appointed company i.e. the site is ‘unserved’. This includes areas which are supplied by private, unregulated supplies. This criterion has to be met for both water and water recycling services;
  • If the existing appointed company consents to the transfer of that area.

The alternative supplier (the “NAV appointee”) will hold an Instrument of Appointment and therefore have all the same duties and responsibilities to the customers within the NAV appointment site as the previous statutory supplier.


Every NAV must have access to adequate water resources and/or water recycling facilities in order to service the customers on the site. If the site is within the Anglian Water statutory area of supply and the NAV does not have direct access to its own water resources and/or water recycling facilities, these services can be purchased from Anglian Water Wholesale.


For water, this is purchased in the form of a bulk supply of water delivered to an agreed point, usually at the site boundary.


For used water, this is purchased in the form of a discharge point, usually at the site boundary, where bulk effluent is discharged into our water recycling system.


The supply of these services is governed by legal agreements, which are negotiated between the parties.


NAV enquiries can be submitted through our customer portal, InFlow.


Our service level is 15 business days. Where additional modelling work is required, our Pre-development team will be in contact.


You can also access InFlow by copying this link and pasting into your browser: 


Our 'User Guide' provides you with some helpful information on how to register on InFlow and use the service.


For queries in regards to current NAV appointments please email


On 8th May 2018, following a consultation process, Ofwat issued new Guidance for bulk charges from incumbent companies to NAVs. Anglian Water has consulted with NAVs and other stakeholders on its proposals for new 'NAV tariffs' to comply with this Guidance.


We identified a number of issues in our exploration of the “wholesale-minus” calculation set out in the Guidance. Our aim with the consultation document was to test the views of NAVs and other stakeholders on our draft proposals to address these issues and to capture feedback through the questions set out in the consultation. We wanted to ensure that we had fully reflected upon respondents’ views and the evidence they submitted before we concluded on the principles that guide our approach and the various trade-offs we have to address in our tariff proposals.


The consultation closed on 16th November 2018.


In the interests of transparency we have placed responses to the consultation on our website. Respondents were asked whether they wished any parts of their response to be redacted on the grounds of commercial confidentiality, and if so to provide a version with the relevant sections blacked out.


Following receipt of responses, we prepared a further document set out below which summarises respondents’ views on the 26 questions set out in the consultation and explains our conclusions on those views and the changes to our NAV tariff proposals that we made as a consequence.


We have now published our NAV charging arrangements for 2022/23. These are set out below.



Our code of compliance

Everyone within Anglian Water needs to recognise the importance of competition law. As a company we are keen to support the introduction of effective competition where beneficial to customers.


The code will be reviewed on an on-going basis and changes made as necessary in order to ensure on-going compliance following the full non-household retail market opening in April 2017.



Compliance code