London City Airport

The challenge: a complex and constrained environment

When it first opened, London City Airport (LCY) only carried a few hundred thousand passengers a year. Over the next few decades, small-scale improvement projects helped to accommodate the steady growth in travellers. But with passenger numbers reaching 5 million by 2019, major expansion was essential.

LCY takes full advantage of the distinctive winding geography of the River Thames. The compact site – on the quay between the Royal Albert Dock and the King George V Dock – runs parallel to one of the straighter sections of the river. 

But its location means there will always be limited options for the airport to expand. Add to this the complexities of working in an inland marine environment, at the edge of one of the world’s busiest cities. The project involved building over open water, with variable weather conditions.

The expansion programme also needed to focus on minimising environmental impact, especially the risk of contaminating the waters around the site.

The BAM solution: an adaptable approach to innovation

Following a wide consultation process and extensive research, BAM used the least environmentally and ecologically disruptive method to construct the 75,000 m2 extension to the concrete deck over the King George V Dock. 

The expanded deck supports critical infrastructure including eight new aircraft stands, a parallel taxiway and a world-class extension to the passenger terminal.
Sections of the dock wall had to be demolished to enable the new deck to be tied in. At the same time, BAM constructed a partly submerged service trough and drainage channels, as well as installing around 90 land-based piles next to the airport entrance.

Using marine piling barges, BAM installed over a thousand new piles in the waters of the dock while the airport maintained live operations. The concrete for the deck was delivered using over 6,000 pre-cast sections and almost 20,000m3 of air-entrained concrete poured on site. 

Delivering and removing materials by barge saved over 1,170 lorry journeys. And BAM closely monitored water quality throughout the project: adapting its methods to cut the risk of pollutants reaching the river.

During the project, BAM built sections of the deck incrementally: each new section forming the base from which to build the next one. This approach involved planning a complex sequence of logistics to keep the project on track.

The world’s first AI concrete strength prediction engine was used in these critical stages. By combining historical concrete curing data, real-time measurements from the pour and local weather information, the system helped the team to plan workflows while ensuring the lasting strength of the concrete[JM1.1].

BAM also used Building Information Modelling (BIM) to reduce environmental impact during construction and identify efficiencies that were incorporated into the final design of the new infrastructure. 

The results: leading-edge sustainability and quality

This major development programme has allowed LCY to transform its facilities and helped it to become one of the UK’s most sustainable airports.

 BAM completed the project without any incidents of pollutants entering the water. Over 5,000 tonnes of excavated material was reused to support piling operations, thanks to innovative use of a biodegradable polymer mix. 

Over 26,000 tonnes of spoil were carried downriver by barge to support a restoration project at Rainham Marshes – managed by the RSPB and Natural England – where it’s being used to improve bird habitats. 

In all, 75,000m2 was added to the footprint of the airport, delivering more space, amenities and choice for passengers.