Starting Monday, Regional Rail riders on the Media/Elwyn line will experience a major interruption in their commutes.

SEPTA is replacing all train service between the Elwyn and Swarthmore stations until Sept. 4, the transit service announced. The shutdown, which includes the Media, Moylan-Rose Valley and Wallingford stations, will allow for construction on the Crum Creek Viaduct to begin.

Shuttle buses will replace all train service for these stations on weekdays and weekends. There will be express service from Elwyn to Swarthmore for customers traveling into Center City from 5:16 a.m. to 8:09 a.m. After 8:09 a.m., shuttle buses departing Elwyn will stop at Media, Moylan-Rose Valley and Wallingford before arriving at Swarthmore; passengers can transfer to Regional Rail trains to complete their commute into the city.

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In the opposite direction, trains will travel to Swarthmore Station, where passengers can then transfer to shuttle buses, which will make stops at the four closed stations.

NBC10 reports that some 1,600 passengers will be affected.

As part of the Rebuilding the System Program, SEPTA is working to replace the 925-foot-long, 100-foot-high bridge at the Crum Creek Viaduct. It was initially constructed in 1895 and repaired in 1983. Construction on the $89.9 million project began in winter 2015, and isn't expected to wrap up until next summer.