Costain is planning a series of overnight closures of a short section of Main Road, Blackrock to allow the construction of a deep manhole in the highway.

These night-time closures, however, will not affect the A465 Heads of the Valleys Road between Brynmawr and Gilwern.

The road closure will start at 8pm each evening and re-open at 6am the following morning. The work is programmed for the nights of Tuesday February 28,Wednesday March 1, Thursday March 2 and Friday March 3, Monday March 6, Tuesday March 7, Wednesday March 8, Thursday March 9 and Friday March 10.

The road will not be closed on Saturday March 4 or Sunday March 5.

Costain says it will aim to reduce this period if possible and to undertake the noisy operations before 10.30pm.

There will be noise monitoring throughout the construction period and emergency access will be maintained at all times.