Work has begun on a new $2.1 million stopbank on the Ashley River near Rangiora in Canterbury.
The 2km stopbank will be constructed in two stages on land owned by the Canterbury Regional Council, the Waimakariri District Council and A&P Showgrounds.
It will run between River Road and the existing Ashley River stopbank and extend from West Belt to the Railway Bridge.
The Canterbury regional council's principal river engineer says the stopbank upstream of the bridge at Rangiora was known by locals as "Break-Bank" because it breached on eight occasions between 1868 and 1953.
Ian Heslop says the new stop bank will capture breach flows, returning them to the river upstream of the railway bridge.
The first stage will be completed by September this year. The second stage is expected to be put out to tender in 2014 and completed by April 2015.