Work on Thatcham’s second flood basin gets under way next Monday, while plans for the third were unanimously approved by West Berkshire Council last week.
Construction at land just off Tull Way will create a bund that will hold back flood water coming off the hills to the north.
It is the second bund to be built at Thatcham, with the first at Cold Ash Hill completed three years ago.
Work is expected to be finished by October 2017.
Jon Winstanley, the council’s projects manager, said: “We are looking forward to delivering this important flood defence scheme for Thatcham.
“We will be working closely with all parties concerned to ensure the works cause as little inconvenience as possible.”
Last Wednesday councillors on the eastern area planning committee gave their backing to the third bund, to be built on land north of Floral Way, opposite Foxglove Way.
This is a similar scheme, but three mature trees will need to be removed.
Committee chairman Graham Pask said: “We are always concerned when trees are removed but we were assured it’s the only way.
“We are obviously supportive because there’s nothing worse than houses being flooded. Imagine three feet of water in your house – it’s a nightmare.
“It happens and is gone in about half a day. But the consequences last for over a year, so it went through unanimously.”
A fourth bund is also planned for the Francis Baily area in south east Thatcham.
Severe flooding hit 1,100 houses in the town in 2007.