River dredging to fix flooding

Dredging has started on a Blenheim river that lost several sections of riverbank in the 7.8-magnitude earthquake, causing flooding upstream in heavy rain.

The Marlborough District Council started dredging the O¯ paoa River on Tuesday as part of a $200,000 project to bring it back down to pre-quake water levels.

Slumping of the O¯ paoa riverbank, brought on by the Kaiko¯ura earthquake in November 2016, caused water levels to rise in the lower O¯ paoa and Taylor River by up to 30 centimetres.

The Taylor River has since become more prone to flooding in heavy rain, especially around the amphitheatre in central Blenheim.

But the council’s new dredging project is set to pull the plug on the ongoing flooding issues by dealing with channel narrowing and sediment build-up in the lower O¯ paoa River.

The council has already reduced the amount of aquatic weed in the river, which helped with river levels and water flow.

Council rivers and drainage engineering manager Geoff Dick said this next stage would see the O¯ paoa River’s edges returned to their original position.