Police will begin a trial at the Metropolitan crossing on EM Bypass from Friday to examine whether traffic will be severely affected once a stretch of the intersection is handed over to the Metro Rail authorities to complete construction of the pillars.

Two Metro pillars at the crossing do not have pier caps.

On Wednesday, the Rail Vikas Nigam Limited (RVNL), the agency executing the Metro link between New Garia and the airport, handed over the Chingrighata site where traffic diversion was in place to the police.

The RVNL wants to complete the work at the Metropolitan crossing by first erecting pier caps on each of these two pillars and then placing a 100-metre-long prefabricated viaduct on them.

The viaduct will connect the twin pillars at the Metropolitan intersection with two others built on one side of EM Bypass, along the Ultadanga-bound flank.

Once the viaduct is built, Metro — now operational between Ruby and New Garia on the Orange Line — can be extended to Beleghata station with the rakes switching tracks that would be placed on the viaduct.

“The traffic trial will continue for five days during which we will examine the movement of vehicles on whether the flow is affected,” said Yeilwad Shrikant Jagannathrao, deputy police commissioner (traffic).

“If the trail is successful, we will hand over the Metropolitan crossing to RVNL to start the work on twin pillars. If not, we might propose a few things that would have to be implemented before the work begins.”

At the Metropolitan intersection, the twin pillars — No. 288 and 289 — stand next to each other on the Ultadanaga-bound flank of EM Bypass.

The RVNL built them last year blocking a portion of the road for three months. Since the twin pillars forced traffic to squeeze through a gap, the RVNL extended the road on the western side near the Bypass Dhaba (an eatery) so that some vehicles could move easily along the Ultadanaga-bound flank.

“The piers were built without pier caps. We need three months to complete the remaining work at the Metropolitan crossing,” said a senior RVNL official.

The chief commissioner of railway safety (CCRS) expressed dissatisfaction over the unfinished work at the Metropolitan intersection on EM Bypass when inspecting the Orange Line for the proposed extension of the Metro link beyond Ruby in March.

Wondering why no provision was made for the viaduct on which rakes would switch tracks and no foot-over bridge (FOB) built near the Beleghata station, the CCRS had asked the Metro authorities to speed up work.

The RVNL had then said the work couldn’t be completed because the police didn’t give the necessary traffic block — a charge that senior officers from Lalbazar had strongly refuted.

Senior police officers had said the block at the Metropolitan crossing would be made available once the ongoing work — for pillar construction — at the Chingrighata crossing was over.

On Thursday, the traffic diversions that had to be put in place to facilitate the Metro work were withdrawn.