Part of Beccles Road in Oulton Broad will be closed to southbound traffic from Monday (April 11) during work by UK Power Networks.
A stretch of the carriageway between numbers 50 to 120 Beccles Road will closed to traffic travelling towards Beccles until May 31.
A diversion via Cotmer Road, Elm Tree Road and Castleton Avenue will be in place.
The northbound lane towards Oulton Broad will remain open.
A spokesman for UK Power Networks said: 'UK Power Networks is investing £100,000 in a project in Oulton Broad to upgrade the electricity network by undergrounding some power lines. It will increase the resilience of power supplies for local residents and businesses by renewing equipment which delivers power in the local community.
'Work is scheduled to start on Monday to install 250 metres of new underground electricity cables in Beccles Road, then switch off and dismantle a corresponding length of overhead power lines.
'We have worked closely with the local authority in planning this project, which involves making a series of excavations to install a line of ducts which will contain new electricity cables.
'The work is due to be completed by May 31, although we always aim to complete our work ahead of schedule wherever possible.
'Traffic restrictions will be necessary to carry out the work safely.'
Will you be affected by the closure? Email kathryn.bradley@archant.co.uk
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