Improvements to Torrington's sewer network will see three roads closed, starting this month.
South West Water and H50 will begin the £197,000 scheme on January 21, which will take around eight weeks to complete.
It is part of a five-year £42 million investment across the region to improve sewers.
355 metres of sewer will be improved in the town to improve services for residents and businesses.
Project manager Stephen Cross said: "This is a real investment in Torrington's future. Without this necessary work the sewer network will continue to deteriorate. That can lead to collapses – which cause pollution, flooding and odour.
"We will be working hard to minimise disruption to the public and businesses as far as possible while completing these essential improvements."
It was hoped roads would not need to be dug up but the state of Torrington's sewer networks has meant some need to be completely replaced which will involve digging them up to do so.
The planned closures are as follows:
- Well Street between January 21 and February 20
- Potacre Street between February 18 and March 1
- Castle Street between March 1 and March 8