Metro matters, so does safety

Mass Rapid Transit (MRT) Systems such as Metro rail are major urban infrastructure projects which pose many unique problems and challenges, many of which can have catastrophic consequences on society and the social fabric if not properly planned and handled at every stage of their implementation – planning, design, construction, commissioning and operation. The fact that they are built within a living, bustling urban environment and extend over the whole metropolis makes them very different from other infrastructure projects. They, therefore, demand a strong legal foundation and complex organisational structures requiring the cooperation and close interaction between several public and private agencies.

They also require long periods of construction and pre-operational testing, which cannot – and must not - be hurried or short-circuited to meet unrealistic deadlines imposed by political or other compulsions. This is why the world over a tremendous amount of attention and care is given to detailed and meticulous planning of all aspects of the project - whether technical, legal or financial - before the project is even taken up for implementation. I was fortunate to have been intimately involved in the planning, design and construction of three MRT systems in Singapore, Taipei and Bangalore, and studied several others around the world. This short article will endeavour to describe some of the lessons that these projects have taught us. These assume a particular relevance in the light of the many accidents that have been occurring in the three metro projects currently under construction in Bangalore, Delhi and Mumbai, which have highlighted the imperative necessity of adequate safety at all stages of implementation.

Audit trail

Accidents during construction do occur, sometimes even with the best of care and attention. However, disasters that happen owing to inadequate planning or faulty safety and quality assurance (S&QA) structures are not “accidents” but negligence. In any S&QA structure, there must be a clear audit trail from inception to completion for every aspect of the project, so that should anything go wrong its reason can be ascertained, cross-referenced to other areas of the project so that measures are taken to prevent future recurrence. And lastly, but not unimportantly, responsibility can be fixed since this will have a great bearing on any subsequent legal proceedings. The organisation must, therefore, be so structured that there is adequate oversight by third parties to avoid bias and complacency. For example, in both the Singapore and Taipei MRT projects the detailed design of the system (whether done by detailed design consultants or by the contractor) was stringently scrutinised by the in-house experts of the MRT Authority’s General Consultant (GC). The GC staff were housed in the Authority’s offices, and they had the primary responsibility for specifying the design, construction and operational standards and criteria for the system and to ensure that the designs submitted to them met them completely. Designs were checked and approved by the GC at 30%, 60%, 90% and 100% stages of development, so that there was continuous monitoring throughout the whole design process. Designs could be submitted to the GC only after a comprehensive internal QA procedure had been met, documented and proved by the Detailed Designer (DD). Penalties were imposed at every stage in the event of delays by the DD, which would weigh against them when bidding for further work.

Lastly, the Authority employed its own set of experts who oversaw all of the work handled by the GC. There were, thus, three levels of oversight – the internal S&QA system within the DD, the GC (who proof-checked and approved designs) and the Authority’s employees who oversaw the GC’s work. As a result we worked under the tremendous triple-pressure of creating good designs, documenting S&QA adherence and meeting submission deadlines. It just made us extremely efficient, focused and careful in everything that we did. This is why both these huge projects were completed on time and within budget with almost no accident at all! Since the audit trail was very clear, the Authority was on very strong ground when any disputes arose. 

Special challenges

Underground MRT systems present a host of other special challenges – not all of which can be foreseen or provided for in advance. For such systems, therefore, the need for much greater vigilance, testing and safety precautions cannot be over-emphasised. Underground construction can be treacherous since the number of unknowns and imponderables is very high. Hence, extensive and comprehensive soil testing is essential. Unfortunately, this is one area that government authorities and contractors alike greatly economise on, based on “past experience”, “educated guesswork”, a gamble and a prayer. In small jobs or in uniform (isotropic) soil conditions this will perhaps work, but in extended constructions and/or in very variable subsoil conditions this approach is very risky – and there are innumerable cases where the gamble has resulted in disasters of many kinds with extensive ramifications for all concerned. Tunnelling operations – whether by Tunnel Boring Machines or by Cut-and-Cover construction or NATM techniques – are always attended by major risks, which require a great deal of attention to be paid to preventive measures. Ground subsidence can cause failure or even collapse of buildings, if the soil is not strengthened beforehand. Methane from organic deposits (and landfills) can travel great distances dissolved in ground water and can cause explosions elsewhere in the tunnel at the slightest spark. Prevention and control of groundwater seepage into excavations and tunnels is extremely important. 

Much more can be expatiated on the above subjects but the intent of this article is only to highlight that there is a very large number of complex safety and other issues in the implementation of any MRT project, whether elevated or underground, which require the attention of experts in the respective areas. In overseas projects, it is almost standard practice to hire the services of the best professionals in the world, pay them well and train a large number of bright local engineers for future works. Unfortunately this is a major area of weakness in the organisation of the Indian MRT projects since we tend to feel that there’s nothing that we do not know, and very little that these highly paid expatriates can teach us. And we are, therefore, the losers. An ounce of prevention is better – and much less expensive – than a ton of cure. And finally, let us hope that the recent spate of accidents on  MRT projects in the major metros are isolated incidents and not the tip of the iceberg. 

(The writer is a consultant and an eminent expert with over 25 years experience in mass rapid transit systems and transportation infrastructure in India and abroad. He was formerly Executive Director of Bangalore Elevated Light Rail Transit System (ELRTS), which was abandoned by the Government in favour of Namma Metro presently under construction.)