After a six-month suspension, train service has resumed on Waterbury Branch Line, officials said.

The service resumed Monday between Bridgeport and Waterbury. At 27 miles, the Waterbury line is the longest of three branches.

In April, buses replaced rail service because of a decrease in ridership caused by the coronavirus.

Buses allowed riders to maintain social distancing and allowed rail line infrastructure improvements to progress more quickly.

The $116-million project aims to enhance service reliability and enable increased Waterbury Line rail service in the future.

There are 15 trips daily on the single rail track; eight inbound toward Bridgeport and seven outbound to Waterbury

One of the features of the work are four rail sidings that allow trains to pass. Once operational, and in conjunction with the passing sidings, up to 10 trains per hour could be run on the branch line.

Completion of the signal system and PTC is scheduled for December 2020, and both are expected to become fully operational by mid-2021.

Adding more trains would be based on ridership and additional funding for the line.

Bridge repairs were also made to three major rail bridges in Derby, Seymour and Naugatuck. The remaining work will be completed in 2021.

“Waterbury Branch improvements, not only to support and improve current operations but also future enhancements in the service, have been long overdue,” Transportation Commissioner Joseph Giulietti said in a statement. “I extend my appreciation to our customers who patiently tolerated the inconveniences, while at the same time our crews were able to accomplish so much work in such a short period.”

All rail customers are encouraged to pre-purchase their rail tickets before boarding. Customers may use the MTA eTix smartphone application or ticket vending machines at New Haven Line stations.

The Waterbury Branch Line schedule is available online.