When it’s finished the Morpeth flood scheme will protect more than a thousand homes and businesses from floods like those in 2008, which caused widespread flooding in the town.
The scheme is being funded by the Environment Agency and Northumberland County Council.
Birse will build new flood defence brick walls broken up by natural stone at the entrances to three flood gates, which will allow easy access to the green area and riverside.
These flood gates will be closed by the Environment Agency if flooding is likely.
Anthony Myatt, Project Manager at the Environment Agency, said: “This is an exciting milestone in this important project. High Stanners is an area of the town at greatest risk of flooding, so we are pleased to be starting on the new flood defences in this area.