Big fix of Rangitata started

Major work to repair damage caused during the 2019 Rangitata River flood is under way as the regional council joins forces with other agencies for a wider restoration project.

The river, parts of which were severely damaged in the flood, will soon be protected from a similarscale flood.

Environment Canterbury chairwoman Jenny Hughey said the work was urgently needed for the safety and security of the Rangitata community.

It is hoped the work would be complete by the end of August.

ECan senior river manager Leigh Griffiths said that after the flood, the priority was to stop the outflow of floodwaters from the river onto the adjacent floodplain and over key roads.

‘‘Emergency works were undertaken to retain ongoing and future flood flows within the main channel,’’ Griffiths said.

‘‘Current works to address the immediate flood risk to the community include extension of the emergency embankments and construction of stopbanks and gravel groynes at the three breakout locations, and strengthening of existing rock stub groynes and construction of additional groynes adjacent to the Rangitata South Irrigation Ltd ponds.’’

The work is expected to cost about $1.3 million, with nearly twothirds funded by the Government through its Covid-19 response fund.

The remaining 36 per cent of the cost will be co-funded by ECan, Waka Kotahi NZ Transport Agency, Rangitata South Irrigation Ltd, KiwiRail, Timaru District Council, Ashburton District Council and Transpower.

Te Ru¯ nanga o Arowhenua spokesman Karl Russell, who also chairs the river restoration committee, said the work had been ‘‘a long time coming’’.

‘‘It’s been a great collaborative effort. But to be honest, we’re only at the very start of the journey. We realised after the floods that a new approach to protecting the river was needed,’’ Russell said.

‘‘Ultimately, we would like to see the full restoration of the river.’’

During the December 2019 flood, river flows peaked at 2307 cumecs, while the flooding caused significant damage to road and rail that effectively cut the South Island in two for several days, as well as destroying power pylons and farmland.

‘‘We are fortunate to have the support of adjacent landowners and other infrastructure providers to allow easy access for our contractor and their equipment,’’ Griffiths said.

‘‘The biggest challenge is that much of this work is either directly in the riverbed or adjacent to it, so managing the works site over several months with variable weather and river flow conditions is likely to require some agile construction skills.’’

Griffiths said planning was underway to follow up this work with replanting of vegetation that was lost in the 2019 flood.

‘‘The investigations on natural infrastructure enhancements are for works that would be completed within the threeyear (2021-2023) timeframe for works funded by climate resilience funding from the Provincial Development Unit,’’ she said.

‘‘Robust scoping and community engagement is required prior to the development of detailed work plans.’’

The work comes at a time when the Rangitata River is under the national microscope.

In February, Department of Conservation director-general Lou Sanson announced a ‘‘jobs for nature’’ project to restore the river was in its early stages, while he also confirmed a multi-agency group had been established to push through further projects down the line.

Griffiths said it was an opportunity to align work in the area with ru¯ nunga and other key agencies ‘‘to prioritise the health of our waterways and optimise our joint resources for greater long-term impact’’.

‘‘The work could include planting, weeding, wetland and mahinga kai enhancement.’’

‘‘We’re only at the very start of the journey. We realised after the floods that a new approach to protecting the river was needed.’’

Karl Russell

Rangitata River restoration committee