I have been an avid public transport user since 2003, even more so after I sold my car in 2017.

As a long-time transport engineer who worked for decades on Singapore's public transport system, I retain a keen interest in this area. I am glad to see that public transport has become more reliable over the past few years - a point I am sure many other regular users of public transport will concur with. With more new rail lines, and more buses on the roads, the public transport system is more convenient, well connected and comfortable.

While occasional train delays may occur, gone are the days of frequent and prolonged delays, as well as the chaos resulting from train breakdowns.

There is also very little to complain about regarding buses.

The Land Transport Authority (LTA) says that over the past 12 months, the MRT network - as a whole - clocked an average of about 955,000 train-km before encountering a delay lasting longer than five minutes. Mean kilometres between failure is an objective measure of rail reliability that is used by many metros internationally. Singapore's current performance is on a par with cities such as Hong Kong and Taipei in terms of rail reliability.

The improvement is reflected in recent surveys by the Public Transport Council, or PTC (of which I used to be a member), that show an overall improvement in passengers' perceptions of rail services. According to the 2018 PTC Satisfaction Survey, the mean satisfaction score for reliability of MRT services improved from 6.7 in 2017 to 7.6 last year.

DELIBERATE PLANNING AND EXECUTION

The improvements in rail reliability did not occur by chance. They resulted from a disciplined and systematic attention to the problems affecting our rail network.

The public transport operators and the LTA have been spearheading many improvement programmes, such as renewing ageing rail assets, intensifying maintenance and committing more trained manpower.

Like all machinery, the train systems built in the 1980s and 1990s will age and require more attention for upkeep. The oldest lines - the North-South and East-West lines operated by SMRT for about 30 years - are the ones needing immediate attention.

Those of you with sharp eyes may have noticed that since the end of 2016, all the blocks of wood under the rails (called sleepers) have been replaced with hardy concrete ones along these two lines to improve the riding quality. With the completion and stabilisation of the new signalling system, there have been fewer train delays caused by signalling faults.

The 66 trains in the first generation are being progressively retired and will all be replaced by 2024. The new trains will have smart self-diagnostics to check their operating health frequently. This will ensure smoother services, and cut down on the number of train faults and breakdowns. Similarly, the other ageing lines, such as the North East Line, Circle Line (CCL) and Bukit Panjang LRT, are also undergoing renewal.

One challenge for the MRT is that it needs to schedule maintenance around the long hours of operation from about 5.30am to midnight daily. Most commuters don't notice such work except when it is done on escalators and lifts in the stations. Most other maintenance services on the trains and tracks take place outside operating hours. After doing the necessary safety checks and set-up procedures, maintenance crews have only about three hours daily to perform their jobs.

The early closure and late opening of selected MRT stations since December 2017 have given the maintenance and renewal teams some respite and they are able to complete their work faster. Yes, this may cause some inconvenience for travellers, but ultimately, it benefits all.

IMPROVING COMMUTING EXPERIENCE CONTINUOUSLY

The public transport operators are also working hard to improve the commuting experience.

For example, one common complaint is that trains are too crowded during peak hours, and commuters see train after train stopping but are unable to board them as they are too full. This is where the newly introduced service ambassadors, who are neatly dressed in SMRT and SBS Transit (SBST) uniforms, come in. SMRT employs about 400 of them during peak hours to assist customers, perform crowd control, as well as look after the safety of commuters at the station platforms and concourses. Similarly, SBST employs about 200 such ambassadors for the lines they operate. During any train disruptions, they also provide welcome assistance to passengers.

Another common complaint of passengers is the air-conditioning on trains - it is either too cold or too hot. This is not a critical factor to keep the trains running, but our journey experience can be coloured by the state of the air-conditioning. According to SMRT and SBST, a total of about 100 staff work through the night to ensure that the air-conditioning system within the trains is properly serviced and maintained.

Some may wonder why we need any staff on driverless trains. Years ago, we had lift attendants, but as lifts became better, we did away with them.

SMRT informs me that the roving staff on the CCL are there to assist passengers in emergencies, look out for security threats and also take control of the train in the unlikely event of a fault with the driverless system. They will take manual control and drive the train to the nearest station.

FAIR SHARING OF COSTS TO SUSTAIN A QUALITY PUBLIC TRANSPORT SYSTEM

There is a significant cost to ensuring that Singaporeans can all enjoy a reliable public transport system. Money has to be spent on renewing systems and on better equipment. Operations and maintenance workers need to be recruited and upskilled. These efforts need to continue on a sustained basis.

The additional costs have largely been borne by the Government and rail operators in recent years. Over the next five years, the Government will spend about $4.5 billion on renewing rail operating assets.

High state funding keeps Singapore's public transport fares affordable and among the cheapest across advanced cities. There is also financial help for those who need it.

As we continue to reap the rewards of a more reliable public transport system, there are important questions that we need to ask ourselves.

What are these questions?

Should the additional operational cost be borne solely by the rail operators? If so, I think it will not be long before they go into the red and close down.

Should the burden be passed on to taxpayers to keep on increasing the government subsidy? Taxpayers are already subsidising public transport operations, in addition to paying the upfront capital costs of infrastructure. There has to be a reasonable limit to the level of government subsidy as otherwise it places an additional burden on the taxpayers.

Should it be paid solely by passengers? This would result in unreasonable fare hikes and defeat the policy of encouraging more people to use public transport.

An equitable sharing of the costs between operators, government and passengers is preferred. At present, for every $1 of operating cost for rail operations, around 50 cents is paid for by commuters, around 30 cents is paid for by taxpayers in the form of government subsidies, and around 10 cents is paid by operators' non-fare revenue. The remaining 10 cents is a loss that is being borne by the operators.

Should this balance be shifted?

If passengers are to bear more of the cost, this will have to mean paying higher fares. But any fare increase must be justifiable, the total fare must remain affordable to the majority, and extra help in the form of transport vouchers or other concessions must continue to be given to those who need it.

• Gopinath Menon was chief transportation engineer in the Land Transport Authority/Public Works Department from 1991 to 2001 and a former member of the Public Transport Council.