East London train travellers are being asked to plan ahead due to maintenance works scheduled by Network Rail over several weekends in November and December.
More than 3,800 metres of rail, originally installed in the late 1960s, on the c2c network will be replaced as they have worn out over time, Network Rail said.
This is to help reduce the risk of defects that could cause delays to services.
Network Rail will also be repairing faulty drainage pipes next to the platforms at Chalkwell station in Essex.
If left unfixed, excess water could compromise the track quality, it said, potentially causing a bumpy ride and necessitating speed restrictions on trains.
The maintenance will also include other essential track work along the c2c routes, as well as overhead line and level crossing maintenance.
Simon Milburn, infrastructure director for Network Rail Anglia, said: "Our work over November and December is vital to keeping trains running safely and reliably in future.
"We’re really sorry for the disruption to c2c passengers, but our engineers need to get out on track and get these jobs done."
Laura McEwen, operations and engineering director for c2c, added: "Once installed, the new rail will last another 50 years, so we hope that people can understand why this work is necessary.
"We are sharing details now of exactly how services will be impacted to give people the chance to plan ahead.
"As ever, we are committed to our customers and our staff will be on hand to give people assistance with their journeys.
"While Network Rail delivers this work, our team at c2c will also be using the time wisely to carry out essential improvement works at stations."
Due to the engineering works, rail replacement buses will be in operation on parts of the c2c network on the following weekend dates: November 3, November 16 and 17, November 23 and 24, November 30, December 1, December 7 and 8, and December 15.
On these dates, buses will replace trains between Pitsea and Shoeburyness, with certain exceptions.
On November 17, rail replacement buses will operate between both Basildon and Shoeburyness, and Ockendon and Shoeburyness via Tilbury.
On December 8, rail replacement buses will operate between both Pitsea and Shoeburyness, and Grays and Shoeburyness via Tilbury.
On December 15, rail replacement buses will operate between Pitsea and Southend Central, with a train shuttle running between Southend Central and Shoeburyness.
The Rainham line will not operate on November 3, November 17, November 24, or December 8, with rail replacement buses running between Upminster, Rainham, Purfleet, and Grays.
During these engineering works, trains will only serve London Fenchurch Street and will not call at Stratford but will stop at West Ham.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here