Major repair works on the Horns Mill railway viaduct are expected to cause traffic disruption for up to 19 weeks.
The work starts on Monday 20th January and is scheduled for completion by Tuesday 26th May 2020.
Whilst the works are taking place there will be one way traffic under the bridge, controlled by temporary traffic lights.
The road will be completely closed overnight from 9pm on Monday 20th to 6am on Tuesday 21st to allow scaffolding to be installed around the bridge.
Cracks and damage are clearly visible on the structure, which carries suburban trains, freight and intercity services.
The line was completed in 1924 and is known as the Hertford Loop, running from Wood Green to Stevenage.
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