Kaeo flood risk reduction works progressing well

7 Feb 2014

Work on a $700,000 project designed to reduce some of the worst impacts and risks from the flooding that plagues Kaeo is on schedule and now more than 50 percent complete.

Kaeo floodworks.

Bruce Howse, Land/Rivers Senior Programme Manager for the Northland Regional Council, says the work on the project began late last year and aims to protect the town from destructive, high-speed floodwater rushing through it.

Mr Howse says while the scheme includes a roughly 1km long network of three-metre high stopbanks, it is not designed (nor intended to) stop flooding from occurring.

"What it is designed to do is to deflect damaging, high-speed floodwaters away from the town with a series of stopbanks and essentially convert it into slow-speed 'back-water' flooding."

Mr Howse says the work – at this stage expected to be finished on schedule at the end of next month – is being funded via a roughly 50/50 split between central government ($386,000) and a targetted rate on approximately 2200 local properties.

He says good progress has been made to date overall, with a several-hundred metre long flood wall on the Whangaroa College grounds complete and scheme drainage and the works' main stopbank from the Pohue Pa to the college progressing well. A large spillway cut upstream of those works was also about 50% complete.

Mr Howse says collectively, the Kaeo works will slow the speed of future floods and should make them much less damaging and dangerous.

"It's definitely not a 'silver bullet' solution but it will make it easier for residents to protect flood-prone properties with sandbags and other tools like flood shutters."

"Kaeo is built on a floodplain and has flooded for as long as recorded history. Its position and local geography means a practical and affordable solution to stop flooding from happening competely is simply not possible."

Meanwhile, Mr Howse says a temporary river crossing for machinery to haul earth across the Kaeo River from the spillway to the stopbanks has also been working well.

"The temporary crossing enables material to be hauled across the river with no unnecessary disturbance to the river bed from machinery movements, preventing sediment from being stirred up and maintaining water clarity."

Mr Howse says even with grass seeding and tidying up works (which are dependent on favourable weather/ growing conditions) the council still expects the project will be completed on schedule by end of March.

He says the first real test of the banks could happen at any time, but most likely will come during an event where accumulated rainfall exceeds 100 mm in less than 24 hours.