The pipe work is the final step in an 11-year project by the Water Board

Sixty six routes will be shut in the Vale and St Sampsons areas during that period.

The Water Board says residents should have received a letter telling them about the work, which involves relining old pipes.

The work is the final step in an 11-year project.

The Water Board has so far treated 171 kilometres (106.3 miles) of pipes, with 24 kilometres (14.9 miles) still to be dealt with.

The work was due to finish at the end of 2005, but it is now expected to be completed 12 months early.

Water Board chief executive Andrew Redhead said there would inevitably be some inconvenience, but the improvements were essential.