Kim Chuan Depot | Aedas | Architecture | Transport | Singapore | Singapore

Kim Chuan Depot is the world's largest underground depot, featuring a sophisticated Operations and Control Centre, Mechanised Train lifting systems and automated storage and retrieval systems.

The design brief called for a two-level underground depot with above ground structures. Enhancements were proposed by the design team in response to operator requirements for better operational and maintenance considerations. This resulted in the underground structure being consolidated into a single volume basement with a mezzanine for administration and support functions. Apart from enhancing construction efficiency, this also allows the project to achieve a high score on the Singapore Government's Buildability Standard. Considering human safety as a major concern, putting the basement onto a single level also creates volume. Supported by spot cooling, there is a high degree of passive ventilation.

One of the main architectural challenges was the successful planning and integration of the automated control, maintenance and storage systems and ensuring that they facilitated smooth operational work-flows and ease of access for maintenance. In the basement level, the Operations & Control Centre is hosted to monitor the automated trains that run through all the circle line stations. In the principle workshop area, an Under-floor Lifting System is used to maintain the trains. The system can lift the entire train or individual cars to a maximum of 1.5m.

Another feature on the basement is the automatic storage and retrieval system. At the height of 23 metres, it is the tallest underground automated warehouse system in Singapore. It can handle 2,000 pallets for medium-size items like coupler motors and 22,000 bins for smaller items like nuts and bolts, and the retrieval process takes about four minutes from the moment the operator keys in their request. The vertical stacking improves circulation efficiency, security and provides the opportunity to bring natural light down into the maintenance areas.

Apart from the naturally lit canteen/kitchen facility at level 2 of the above ground structure, skylights are implemented to the basement offices and circulation areas. In addition to improving the quality of these spaces, energy consumption is reduced.

"Initially there were concerns about the idea of opening holes (skylights) into the depot basement, which are treated as highly-secured areas. However through careful planning, sun path studies and 3D presentations we were able to convince the client that this was an important enhancement. The end result is impressive levels of defused natural light in the underground offices." Gruffudd Owain, Principal, Aedas Singapore states.

In consideration of a future expansion, the depot's design allows for three hectares of the roof deck to take the loading of future industrial developments of up to nine storey's high. It also has the capacity for two additional Operations & Control Centres for future lines and expansion.