Managing the legacy of underground infrastructure

Direct by Design

Legacy of underground infrastructure Traditionally, construction of underground infrastructure has been planned and designed for the immediate intended purpose. Now it is becoming increasingly necessary to consider how it might be adapted to future requirements and perhaps alternative purpose in our rapidly changing world. This is a topic being addressed by Martin Knights as part of his recent appointment as chair of a new steering board tasked with producing an industry guideline for the management of underground assets both existing, new and planned for the future.

Martin Knights, Chair, LBA Ltd, UK

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ow clients and operators manage the asset legacy of underground infrastructure is a topic that needs careful consideration. Increasingly it is mandatory for prebuild requirements to demonstrate that infrastructure is not just fit for the intended purpose – with the regard to serviceability, durability, capacity to meet requirements, and be efficiently maintained – it will become necessary for owners to consider adaptability, resilience and possible evolving needs. The point is made clearly by Mark Wild CEO of Crossrail in the UK when he speculated in a recent article in the Economist magazine that the new Crossrail 1 infrastructure in London would last for 300 years or more.

While the underground spaces might well last that long – many underground structures still in use today are already hundreds of years old – the question is will those structures be used for their original purpose such as rail or road transportation in the 24th Century. Maybe Crossrail will evolve into an underground spatial conduit for Crossrail Model of the London underground network

Dec 2021 version 5 or it may become a linear urban underground farm; or a longitudinal data storage facility for one of the giant data harvesters, or maybe a cargo module transit system for quick delivery under the streets of London.

Underground in Action U

My challenge to colleagues is to consider: what will be the legacy of underground infrastructure into the year 2421 The point is that, in addition to the building of new infrastructure, owners and operators will have to continuously manage the legacy of the infrastructure that is already created. For example, the underground legacy in the UK includes the more than 100-year-old London Underground tunnels and stations; the 30 year

old Jubilee Line Extensions; the 100 year old Rothehithe and Blackwall road tunnels under the River Thames and in London, and the 30 year old Eurotunnel railway link under the Channel between England and France among many others.

Managing the legacy not only means maintaining the structures for the existing purpose, it also means ensuring that the existing footprint can be adapted to changes in capacity, new management technology, and possibly even repurposing its use.

The discussion is expanded in the TunnelTalk Underground Engineering podcast It is clear that future regulation will demand more convincing evidence that new infrastructure build is necessary and that it fulfils the contemporary societal requirements to address new goals – new goals that including resilience to climate change; low or zero carbon creation; putting forward convincing economic and social value, measured across a wide spectrum of indicators; and is affordable in construction and operation.

For me, managing tunnel assets from the point of view of logistics; programming in-service refurbishment and maintenance; developing and using new construction materials; and adopting data and predictive driven solutions we will be increasingly in demand. These will also present new market opportunities for the international tunnelling industry and its engaged engineers, consultants, contractors, and equipment and materials suppliers.

In taking up recent appointment as Chair of a new CIRIA Steering Board tasked with producing a guidance document for industry on the management of tunnel assets, these concerns will be studied in great detail.

The purpose of the UK not-for-profit Construction Industry Research and Information Association (CIRIA), is to produce guidelines for standard procedures so that common practices can be embraced by a wide range of stakeholders from owners, operators, legislators, funders, insurers, government agencies, to consultants, contractors and the industry supply chain providers. The Guide will assist technical and commercial decision making and it will share best practices from UK and international sources and will include recent developments in tunnel linings, material science, and data management analysis, observation, control and prediction.

In parallel, and most importantly, the guidance will recognise societal demands with regard to sustainability practices as it applies to underground asset resilience, security, safety, value, net zero targets and the rising influence of natural climate forces.

Preparing the guideline is quite a challenge and not just for managing the expectations of the Steering Board to achieve consensus of opinions about the influences and impacts of

the topics being addressed and agree a common set of priorities but also manage the format of the guideline and verify the reliability of data and references that we will seek in our outreach with industry and supressing individual preferences and biases – and to have it published and available within the set 15-month timeline.

In my current role as a Chair of the consulting firm LBA in the UK, our team has supported the delivery of major new-build projects including Crossrail, Tideway, the HS2 railway, and the planning of future projects including Dublin Metrolink. We also reecntly concluded an in-depth study for the Gateway Corporation in New York to investigate the possibilities of undertaking in-service rehabilitation of the 100+ year old North River railway tunnels under the Hudson River from New Jersey into Pennsylvania Station in Manhattan.

Planning to operate assets over a 100-year life is not somebody else’s problem, it is ours, and my challenge to colleagues is to consider: what could Crossrail 1 evolve into by November in the year 2421. n

Reference

• Rehabilitation option for Hudson rail links, TunnelTalk, Dec 2020 In-service rehabilitation possibilities for the rail links under Hudson River