Nearly $100 billion has been set aside to build road, rail and active mobility projects over the next decade, according to Budget 2020 statements.

Of this, new rail projects account for the biggest chunk, at $87.5 billion. The amount includes money budgeted to complete the Thomson-East Coast Line (TEL), Jurong Region Line, Phase 1 of the Cross Island Line (CRL) as well as advanced engineering studies for the western leg of the CRL.

The Land Transport Authority said the amount includes extensions for the Downtown, North-East and Circle lines. But it did not include a two-stop extension of the North-South line in the north-west slated to be completed by the mid-2030s.

The CRL has the longest lead time, with completion of the 50km rail project linking Changi to Tuas expected to be completed by 2031.

All the others are scheduled to open before that, starting with the TEL, which will be completely up and running by 2023. The only exception is an extension to Bedok which will open in 2024.

The sum also includes civil defence shelters at MRT stations, additional underground spaces created during MRT construction, installation of noise barriers, signalling simulation facilities and an Integrated Train Testing Centre in Tuas.

But it excludes the renewal of operating assets in the North-South, East-West lines, which Transport Minister Khaw Boon Wan said would cost more than $2.5 billion, and is due to be completed by 2023.

So far, about $760 million has been disbursed for this, the LTA said. It also excludes works such as drainage; and a potential new line referred to as 'Seletar Line', which runs east of and parallel to the North-South line.

Bus-related projects amount to $1.3 billion, including the building of depots and integrated transport hubs - which incorporate a bus interchange with an MRT station - as well as the purchase of 450 new buses. These buses, like the 1,000 bought under the Bus Service Enhancement Programme, have started plying.

About $6.78 billion has been earmarked for domestic rail projects for financial year 2020. Meanwhile, $7.2 billion has been earmarked to upgrade the existing road network, such as by resurfacing expressways and maintaining elevated road such as viaducts.

The amount includes new projects such as a road network for the Changi region to accommodate Changi Airport Terminal Five as well as the eastern end of the CRL; an interchange at Senja Road-Kranji Expressway; and expansion of the Kallang Paya Lebar Expressway and Tampines Expressway Interchange and new links to Punggol Central and Pasir Ris.

Some $6 million of the amount has been set aside for the test-bedding of autonomous vehicles.

About $1.45 billion has been set aside for active mobility projects. Expanding the Islandwide Cycling Network from 440km today to 1,320km by 2030 accounts for the lion's share of the funds, while $31 million will be for supporting infrastructure such as bicycle parking facilities, signage to improve wayfinding, footpath widening as well as speed-regulating strips.

In total, all these surface transport projects amount to $97.5 billion. But as with previous Budgets, actual expenditure may differ from what has been planned.

For instance, $40.4 million was earmarked for a stormwater retention pond in the new Bidadari estate, but the actual cost of the flood mitigation measure is now closer to $25 million.