Metra, experiencing a 97% decrease in systemwide ridership, is further reducing train service on its three least-busy lines beginning Monday.

Just one inbound and one outbound train will run per day on the Heritage Corridor line, which serves southwest suburbs between Chicago’s Union Station and Joliet, and the North Central Service line, which serves northwest suburbs between Union Station and Antioch.

Just two inbound and two outbound trains will run per day on the SouthWest Service line, which serves southwest suburbs like Oak Lawn and Orland Park between Union Station and Manhattan.

The changes were announced Wednesday.

“The ridership has been so light on these trains that some of these have been carrying as few as one person, and we thought we should consolidate them,” Metra spokesman Michael Gillis said. “We’re still providing base-level service for essential workers but not running as many empty trains.”

On average, 35 riders per day have been using the Heritage Corridor line, which had been running seven trains per day, since the stay-home order was issued in March. About 65 riders have been using the North Central line’s 10 daily trains, and about 120 riders have been using the SouthWest Service line’s 10 daily trains.

Systemwide, Metra has seen between 7,000 and 8,000 riders per day. Gillis said no further service reductions are planned for Metra’s other eight lines, but Metra will “continue to reassess” that on a daily basis.

Metra announced earlier in April it was projecting a loss of $536 million in revenue in 2020 and 2021, although it is expecting $480 million in federal aid. The service reductions starting May 4 will save about $470,000 per month.

“We just want to make sure people understand this is, hopefully, just a temporary thing,” Gillis said. “If we notice ridership ticking up, we’re willing to add more trains.”