Pedestrians and cyclists have been told to expect disruption, with the work taking place Monday to Friday, 8am-5pm.
Last year Reading Borough Council discovered the section of the 120-year-old wall - between Patriot Place and Weirside - had decayed.
Planning leader Cllr Tony Page said: "These important works are essential to maintaining a key pedestrian and cycleway into the heart of Reading.
"The council apologises for any inconvenience or disruption the repairs may cause and we will ensure every effort is made to keep this to a minimum.'
In December work was carried out, with the excavation and breaking out of the wall and construction of plinths for new guard railings.