MONTREAL -- The REM light rail system has been subjected to temperatures both high and low as part of a series of tests.

During an update on the project's construction on Thursday, CDPQ Infra representatives said more than 200 hours of tests have been run on the network, including subjecting it to temperatures as low as -38 C and as high as 38 C.

Other tests have simulated heavy snowfall, ice, freezing rain and violent wind.

According to the representatives, construction remains on schedule despite the COVID-19 pandemic, with three stations on the South Shore mostly completed, bridges on the North Shore finished and installation of an aerial structure and tracks in the West Island going smoothly.

However, the overall price tag of the project has changed, now coming in at $6.9 billion. Since the last update in the fall, $200 million was added to cover costs connected to the pandemic while another $150 million was spent to work with communities towards improving the project.

Negotiations are ongoing for costs related to the Mount Royal tunnel, though CPDQ said it will assume those added costs.

The update included a 10 per cent reduction in expected overall ridership, which was attributed to more people working from home due to the pandemic.

- With reporting from CTV Montreal's Angela Mackenzie