The new National Underground Asset Register: what does it mean for the energy infrastructure sector?

We explain what the UK National Underground Asset Register is and how it should make life easier for energy infrastructure operators. We also look at how the obligations of asset owners will change following the introduction of the new system.

Key takeaways

Significant efficiency gains: The National Underground Asset Register (NUAR) is expected to deliver significant efficiency gains, reducing scope for accidental damage to infrastructure such as pipes and cables (currently estimated to cost the UK economy £2.4 billion per year) and allowing instant access to the information necessary to carry out excavations (as compared with an average delay of 6.1 days at present). Asset owners will also be relieved of the administrative burden of having to respond to requests for information on their underground assets, as businesses will be able to obtain the data via NUAR instead.
Cost implications: Asset owners will now be subject to a fee to fund the running costs of the NUAR, although it is anticipated that these costs will be less than those currently incurred in responding to individual requests for their data (so the fees should not cancel out the efficiency gains). Current timelines suggest that fees are unlikely to be introduced before 2028.
Compliance obligations: Asset owners will be obliged to provide data on their assets to NUAR. In some cases, the initial upload of data may require additional resources (e.g. because of the volume of assets and/or because current records are not in the format required by NUAR). The exercise of collating and reformatting this data could present a significant administrative burden for asset owners and could involve considerable costs. However, current timelines suggest that asset owners will have 12 months to complete their initial upload and time will not start to run on this time limit until spring 2027 at the earliest. While this provides sufficient time to prepare, we recommend that asset owners begin reviewing their data and establishing the necessary processes now to ensure they are ready to comply by the deadline.

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What is the National Underground Asset Register (NUAR)?

As part of the Data (Use and Access) Act (the "Act") which received Royal Assent in June 2025, we will see the introduction of the new and improved National Underground Asset Register (the "NUAR"). This comprises a digital map of underground infrastructure assets that should be fully operational by the end of 2025 (albeit, as noted above, it will not be fully populated until all data starts to be uploaded in 2027). The Act puts the NUAR on a statutory footing and provides a modernised legislative framework for the sharing and use of data on underground assets.

What will users of the NUAR be able to see?

The NUAR platform allows participating users to immediately view a combined map of all buried assets, for example:

Water and sewer pipes
Gas pipes
Electricity cables
Telecoms cables and ducts
Above-ground furniture (e.g. streetlights and traffic signals)
In-ground furniture (e.g. pipelines and manhole covers)
Transport, local authority and private network assets
Planning considerations

The Government has provided a video demonstration of the NUAR which allows you to see the map in operation.

What are the benefits of NUAR?

To date, accessing such information has typically required contacting numerous different organisations (6-10 on average) and waiting on average over 6 days to compile a complete picture. With the introduction of the NUAR, businesses will be able to get access to the data they need instantly within a single, comprehensive map, with greater confidence that the information is accurate and up to date. This is expected to reduce the number of excavations which result in accidental damage to pipes, cables and other underground assets (there are currently about 60,000 incidents per year, at an estimated cost to the UK economy of £2.4 billion). Asset owners will only need to upload their data once, rather than having to share information individually with those planning and carrying out relevant works – which should enable them to achieve cost-savings.

The enhanced understanding of underground assets provided by the register could also support simultaneous infrastructure work (such as fibre optic installations alongside road and water works), reducing overall project costs and public inconvenience. As the reforms will directly benefit owners of underground assets through a reduced risk profile and better data sharing, it should over time make the energy infrastructure sector in the UK more attractive to investors.

Who will be able to access NUAR?

Initially, the NUAR will only be accessible to registered asset owners in England, Wales, and Northern Ireland through the execution of the NUAR Distribution Agreement. Authorised contractors operating on behalf of these asset owners will also gain access. The government is also considering expanding access:

to certain user groups for safe digging purposes e.g. surveyors and landowners;
for certain use cases, such as electric vehicle chargepoint rollout, flood risk planning and property development, which could be particularly beneficial to retrofitting programmes; and
via third party intermediaries and/or application programming interfaces.

Why not allow access to all?

Access to NUAR is restricted mainly because of concerns about national security - for example, malicious actors could use the data to damage critical UK infrastructure. However, if access is too tightly controlled, NUAR may struggle to deliver its projected £400 million a year of economic growth through increased efficiency. The Government is therefore exploring ways in which access could be widened, whilst mitigating at least some of the security risks. Options include limiting the data that users outside of the asset owner and supply chain community can access and/or subjecting these users to rigorous verification requirements.

What obligations will be imposed on asset owners?

Currently, asset owners are obliged by law to record and share information on underground apparatus and to share it with businesses needing to excavate nearby free of charge, on request. However, there is no standard way of presenting the information, which increases the potential for errors by excavators when combining the data received from asset owners. The current system also requires asset owners to respond to numerous requests for the same or similar information. This means there are significant ongoing and irrecoverable administrative costs, on top of the basic obligation to record and update information on underground assets.

What will change with the introduction of NUAR?

When the NUAR legislative framework comes into force, asset owners will be relieved of the burden of having to respond to requests for information – because excavators will be expected to obtain the relevant data via NUAR instead. However, asset owners will be obliged to:

take a snapshot of information they hold about their apparatus as of a specified date and upload to the NUAR within a specified period;
record additional information about apparatus when installing, maintaining, repairing or otherwise interacting with it;
ensure the information held in the NUAR about their apparatus remains up to date by uploading any new or amended information within a specified period of the change occurring; and
pay fees to fund the operation of the NUAR (although it is expected that the fees will be significantly cheaper in comparison to current costs incurred by asset owners in having to respond to requests from excavators).

It should also be noted that the new draft measures also establish enforcement mechanisms against asset owners who do not comply with the requirements, such as fines and the ability to award compensation to persons who incur damage or loss as a result of an asset owner's failure to upload information to NUAR in accordance with the requirements.

What's the expected timing and what do asset owners need to do?

Depending on the number of assets involved and the form in which records are currently held, the initial upload of data to NUAR could be quite onerous for some asset owners. The Government is currently proposing a period of 12 months to comply with the initial upload requirement. It has indicated that this period would be unlikely to start before spring 2027 at the earliest (we are still awaiting secondary legislation setting out the detail of the above obligations). That said, asset owners may wish to consider whether they would need to allocate additional resources to comply with the upload requirements in 2027 – and whether work is needed to improve existing records to ensure they can easily be uploaded in a format acceptable to NUAR.

What about fees?

The Government has indicated that fees are unlikely to be introduced before 2028. The fees are intended to recoup the operational costs of NUAR, which are expected to be between £5 and £10 million per year. NUAR is ultimately expected to hold data from about 600 asset owners, so the burden of fees should be fairly widely spread – and as noted above, the extra cost is expected to be outweighed by the benefit to asset owners of not having to respond to repeated requests for their data.

How we can help

We regularly advise investors and operators in the energy and infrastructure sector on complex regulatory issues and strategic contractual arrangements. Recent work includes:

Advising Optinet on its new agreement with Unibail-Rodamco-Westfield to install their full fibre network in both the Westfield London & Westfield Stratford shopping centres.
Advising GTC, the UK's largest installer and operator of last mile multi-utility networks, on its new partnership with UK-based ground source heat pump provider, The Kensa Group.
Advising Biogen (UK) Ltd on a cutting green energy supply deal with Ocado.