Singapore’s Thomson-East Coast Line 4 (TEL4), a 10.8-kilometre rail line with seven stations, travels through the East Coast’s residential estates providing alternative travel options to the central business district, education and recreational areas. The line makes up the fourth stage of Singapore’s Land Transport Authority’s (LTA) Thomson-East Coast Line – extending our involvement in stages one and three.

Our team provided multidisciplinary design for three underground stations, more than 4km of twin bored tunnels and one escape shaft. For Bayshore Station, we used land area creatively by designing an island station (one platform positioned between two tracks), resulting in construction and operations efficiencies. We introduced an L-shape diaphragm wall panel design at Marine Terrace and Siglap Stations to enable tunnelling under the proposed underground subway.

TEL4 will improve accessibility for commuters in the East Coast region, saving travel time by up to 50 per cent. With its opening, LTA estimates around 235,000 households will be within a 10-minute walk from an existing TEL station.

Enhancing station design to increase value

Bayshore Station, the last station on TEL4, brings rail connectivity to schools and residential areas. The original concept design featured an underground stacked station requiring extensive underground excavation. We held a value-engineering workshop with various agencies including LTA and SAA Architects to assess the design. Together we generated ideas and proposed solutions to increase the project’s value.  
 
Our team assessed the site’s challenges and proposed revised alignment which would allow space for a shallower island-platform station configuration requiring less excavation. At this new location, we could also design the excavation using the simplest method, open cut, which significantly reduced construction time and cost. The island-platform design has one single platform positioned between two tracks, improving wayfinding, and providing easy passenger transfers between the two tracks. It provides passengers with an easier travel experience. 
 
This station will serve existing and future developments such as Bayshore Park and Econ Medical Centre. In a first for Singapore, Bayshore Station and Marine Terrace Station provide underground parking for around 200 bicycles, offering cyclists a more convenient commuting journey.

Esacalators inside a rail station

The island-platform at Bayshore Station. © Darren Soh

Passengers boarding a train at Bayshore station

The shallower island-platform design reduced excavation. © Darren Soh

Unique tunnelling approach

We designed twin bored tunnels to connect the line’s last four stations which run under existing infrastructure. At Marine Terrace and Siglap Stations, the bored tunnels needed to cross beneath the proposed underground subway connecting the station and entrance. 

We designed an L-shaped diaphragm wall panel for the proposed subway undercrossed by the bored tunnel. This wall panel allowed the bored tunnel to cross to pass beneath the proposed subway without needing to cut through the thick diaphragm wall, resulting in safer and efficient working conditions. 

A busy platform at an underground rail station

Marine Terrace Station

Passengers descending escalators in an underground rail station

Siglap Station

Arup has provided competent and proactive support in resolving technical issues on site. They have performed and collaborated well to help deliver the project successfully.

Wong Thin Hong

Design Manager Land, Transport Authority

Partners & collaborators

SAA Architects Pte Ltd