Unmoved . . . A large pile of wood is building up under the Mataura River rail bridge. PHOTO: BEN ANDREWS

A build-up of debris and branches under the Mataura River rail bridge is causing concern, in light of disastrous flooding in the North Island. But not everyone agrees.

Gore resident Kathleen Richardson said she was concerned tree trunks and branches trapped by piles supporting the rail bridge could cause flooding. Her concerns are echoed by Environment Southland but dismissed by KiwiRail.

She had seen the debris building up beneath the bridge and was concerned there appeared to have been no efforts to remove it, she said.

“Let’s prevent it from happening. Prevention is better than curing,’’ Mrs Richardson said.

Cyclone Gabrielle and the flooding it caused in the North Island had shown the devastating effects a flood could have, she said.

She believed an unusually dry summer in the district had the potential to cause major problems if heavy rain occurred. The ground in the district was usually quite moist but now the water was just going to run off and create issues, Mrs Richardson said.

Environment Southland catchment operations manager Randal Beal was unaware of the wood build-up but was pleased to have the concern raised.

‘‘Build-up of wood can be a risk to stopbanks in a flood as it can be moved downstream and cause scouring of the banks,’’ Mr Beal said.

Environment Southland would assess whether the wood posed any threat to the stopbank infrastructure, he said.

KiwiRail South Island general manager of operations Mark Heissenbuttel downplayed the concerns.

‘‘The build-up of wood under the Mataura River bridge is being monitored and is not of any immediate concern,” Mr Heissenbuttel said.

‘‘We are responsible for the upkeep of the bridge and plan to remove the debris once a team of trained personnel become available.’’

KiwiRail has removed debris from under the bridge in the past.

Gore previously flooded in 2020 when the Mataura River burst its banks. The flooding caused the evacuation of more than 2400 Gore residents and 1500 Mataura residents.

Several projects are under way along the Mataura River to prevent future flooding, including the upgrading of the Mataura and Gore stopbanks.