SINGAPORE - A project to join the main road of Bidadari town to Bartley Road has restarted after a one-year limbo.

Work at the junction of Bartley Road and Bidadari Park Drive – a 1.6km two-lane dual carriageway described by the Housing Board as the estate’s “main transportation spine” – is now slated to be completed by end-2024 or early 2025, over two years past its initial completion date in the fourth quarter of 2022.

Since HDB said in February 2023 that it was “reviewing the completion timeline” for linking the two roads owing to “technical complexities of the site”, no work has been observed at the junction besides the erection of more hoardings.

In response to queries for an update, HDB said in early April that it had been working with a consultant “to review and adjust the design of the new cross junction”.

Its spokesman said a revised design was completed in the fourth quarter of 2023, and that work recommenced at the junction in the first quarter of 2024.

Checks by The Straits Times last week found that a stretch of about 20m of Bidadari Park Drive leading to Bartley Road has been excavated to reduce its elevation.

The HDB spokesman said Bartley Road – a heavily used six-lane dual carriageway – will still need to be raised, but by 0.7m instead of 0.9m originally.

Based on current estimates, HDB expects the junction to be completed “around end-2024 or early 2025”.

Like most infrastructural works, the project was delayed by the Covid-19 pandemic. HDB said in July 2022 that completion would be delayed from the fourth quarter of 2022 to the first half of 2023.

In February 2023, HDB said Bartley Road had to be raised because Bidadari Park Drive was more than 1m higher.

According to HDB, joining Bidadari Park Drive to Bartley Road at its current elevation would result in a steep gradient for Bartley Walk, a small road linking Bidadari Park Drive to Mount Vernon Road.

Construction at the junction came to a standstill thereafter.

Meanwhile, residents in the area are bemoaning the long wait for additional access, which the new junction will provide.

Marketing manager Mandy Tan, 40, said: “It will help ease traffic congestion, especially for those living near the Bartley Road side.”

She cited how residents driving from Tampines via the Bartley viaduct find it difficult to access the estate through Mount Vernon Road because “it is too near the ramp, and traffic is often too heavy for them to filter left”.

“They will have to make a U-turn at Serangoon Avenue 1, and then another U-turn before Upper Paya Lebar Road to get home.”

Ms Michele See, 35, the founder of Canopy Student Care, said she frequently encounters a chokepoint where Woodleigh Link joins Upper Serangoon Road. “Hopefully, when the new road opens, it will bring some relief,” she added.

Retiree Liew Hwei Cheung, 52, said the only access to Bidadari town – a 10,000-unit HDB estate near Toa Payoh and Potong Pasir – from the Bartley side now is Mount Vernon Road.

“It is already quite congested now,” she said. “I can’t imagine what it’d be like when Bartley Beacon (a new Build-To-Order project near Mount Vernon) is occupied.”

Ms Liew added that she found it difficult to understand why engineers had not taken into account the stark difference in elevation between the two roads. “We’re not talking about a nominal difference,” she noted.

Associate Professor Raymond Ong, deputy head of research at the National University of Singapore’s Department of Civil and Environmental Engineering, said he has not come across a case where an existing main arterial road is raised to meet the elevation of a smaller road.

“But as we get more developed, I think such issues will and can occur,” he said, adding that if the road raising has to be done, it is crucial to “incorporate a hydrological study and design a proper drainage system” along Bartley Road, which is built-up on both sides.

A veteran civil engineer previously told ST that “generally, we try not to touch an existing road... not just because it can be disruptive to traffic, but also because an existing road has its own design elements to take into account, factors like drainage, kerbs and other street infrastructure”.

Besides Bartley Road, Serangoon Avenue 1 – an existing road directly opposite Bidadari Park Drive – will also have to be raised.