Spring maintenance work on the Waterbury Branch of the Metro-North Railroad will require temporary busing for a nine-day period in late April and early May, Connecticut Department of Transportation and Metro-North officials announced.

Repairs to the four-track Devon railroad bridge over the Housatonic River on the New Haven commuter line will also require service modifications, the agencies said.

Five miles of old track will be removed along the 27-mile Waterbury Branch, requiring the busing of passengers and schedule adjustments for nine days from April 25 to May 9. Schedule changes will be posted at stations and updated online at www.ct.gov/dot and www.mta.info/mnr, although any changed will approximate existing train schedules.

The Waterbury Branch has stations in Naugatuck, Beacon Falls, Seymour, Ansonia and Derby/Shelton.

Repairing the 1.067-foot long Devon Bridge will involve service and schedule modifications.

Customers who usually transfer to Main Line trains at Bridgeport will instead get off the Waterbury train at a new, temporary Devon Transfer station, cross the bridge and wait for a train to stop on Track 1.

Northbound customers will be dropped off Main Line trains at the Devon Transfer and board a waiting train for the trip to Waterbury and stops in between. The temporary station will hive lights and a public address system.

This six-month, $1 million phase of work involves steel repairs, a new wooden deck and new miter rails on the Track 3 span.

When this bridge work on Track 3 is completed, CTDOT will take the adjacent track - Track 1 - out of service for wire replacement. This will leave three tracks in service to minimize disruption to the New Haven Line, the busiest rail line in America. During this time, Track 3 will be carrying an increased number of trains while Track 1 is unavailable.

Track 3, also known as the inbound local track, will be out of service continuously for six months during the work on Devon Bridge. Because Track 3 is where trains from Waterbury merge onto the Main Line, accommodations will have to be made to branch line service during the six-month track outage.

A new, temporary transfer point will be built where the branch and the Main Line connect, at a piece of track called the “wye.”  Two, four-car length platforms will be built, one on the branch and one on top of Track 3, with a walkway connecting them.

Because Main Line trains will be making an extra stop at the Devon Transfer, about a minute of running time will be added to scheduled trip times on those trains. This change will be reflected in the new schedules effective April 26.

Work will be during daylight hours seven days a week, weather permitting.