Network Rail has begun piling on the 17 mile line between Preston and Blackpool North stations.
The upgrade work is part of the North West electrification, a £1 billion investment to deliver more reliable, cleaner and quieter train services by May, 2018.
The piling is expected to continue for several months and will for the most part will take place over night to minimise the disruption to services and the risk to workers.
Piling is a process which involves installing foundations every 50 to 60 metres for the masts and gantries that will carry electrified wires along the railway.
It is a noisy activity because it involves driving steel piles deep into the ground to provide a secure base for the gantries, as well as the noise from vehicle movements.