The Cuddy Bridge in Peebles will be shut for up to four weeks for the upgrading of a water main.
The closure of the bridge, which is on the A72, will begin on Monday (January 26).
During the closure, an alternative route will be in place via the A703, March Street and Young Street. In addition, the A72 road from the junction of Elcho Street Brae and Young Street will be one-way southbound, and Montgomery Place and Cross Street will also be one-way. There will be restricted parking on March Street.
DS Construction have contacted local residents and businesses, while local schools, which are likely to be affected, have also been informed.