Thames Water has announced plans to close Stamford Street to eastbound traffic from early October until early April 2011.
The work is part of Thames Water's programme to replace Victorian cast iron pipes with plastic ones.
There will be weekend closures to westbound traffic on 21 & 22 August, 28-30 August and 25 & 26 September.
A longer-term eastbound road closure will start in early October, with traffic diverted via Waterloo Road, St George's Circus and Blackfriars Road.
Thames Water says that Transport for London has agreed to alter the traffic lights at the top of Blackfriars Road to enable drivers to turn right into Southwark Street.
Two-way traffic is due to be reinstated in early April 2011.
Householders and businesses will receive individual notification of temporary interruptions to water supply during the works.
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