Kawakawa volunteer storm watchdog Roddy Hapati Pihema rates last week’s heavy rain as the worst he’s seen since Cyclone Bola in 1988.
Despite the completion of the Government-funded $7.65 million Kawakawa Deflection Bank and Otiria/Moerewa Spillway last year, Pihema believes the July 28/29 storm showed the measures were only the beginning of what was needed to safeguard the district.
Floodwaters inundated streets in Moerewa and Kawakawa, including outside the Kawakawa Bowling Club, which Pihema said was only spared because it had been raised after earlier floods.
Northland Regional Council (NRC) rainfall data contradicted Pihema’s assessment but rivers manager Joseph Camuso said Waiomio Valley may have experienced a short, high-intensity event not captured by rain gauges.
After visiting the area, Camuso understood why locals believed it was one of the valley’s biggest floods in recent memory.
Pihema, a Bay of Islands–Whangaroa Board member for the Far North District Council, received more than 60 reports of damage and expected more once assessments in harder-hit areas like Waiomio were completed.
He was concerned the infrastructure might have caused new problems by speeding up water flow. The amount of water in the catchment was overwhelming — the most he’d seen since Bola, he said.
“We spent millions upon millions for flood mitigation in our area and we’re still seeing these issues — and worse than they’ve been in years.
“As much as I respect the work done, we’re starting to see it affecting our people downstream,” Pihema said.
He said the worst-hit areas in Moerewa were on the southern side of State Highway 1. In Kawakawa, the deflection wall was working but not enough to protect businesses, such as Kawakawa Engineering at the eastern end of the town.
NRC’s community resilience group manager Louisa Gritt said hydrology modelling contradicted Pihema’s concerns.
Modelling for the Otiria/Moerewa Spillway and Bridge showed downstream effects at SH1’s Three Bridges were less than 10mm.
The confluence of the Waiharakeke River and Otiria Stream is upstream of that point, meaning flow remains unchanged from before the works.
Gritt said flow previously blocked by roads and railways and directed toward Otiria-Moerewa now follows its natural path toward the Waiharakeke, with no additional water introduced.
The Kawakawa Deflection Bank was designed to divert floodwater from shops, protecting less than 2% of the 1km-wide floodplain and causing negligible change in flood levels, she said.
Camuso confirmed the Bowling Club was not part of the original flood mitigation priorities, which had focused on Turntable Hill, the deflection bank, and the Otiria-Moerewa Spillway.
Pihema warned flooding was becoming more serious because of changing weather patterns and compromised natural drainage from wetland destruction and impervious construction materials.
He said improved maintenance of culverts and drainage systems was crucial, and a network of local representatives was working with FNDC to ensure more regular upkeep.
He feared flooding in the district could eventually cost a family dearly. The public couldn’t always be relied upon to use common sense, he said.
Despite signage and publicity, another vehicle was left in a flood-prone riverside carpark behind Kawakawa’s Te Hononga Hundertwasser community hub — the same spot where Pihema had rescued a woman asleep in her van during a storm weeks earlier.
Pihema acknowledged the financial constraints NRC and the FNDC faced.
“We can identify problems and solutions, but without more central government support, our councils and communities remain hamstrung.”
NRC said it had received $19.1 million in central government funding since 2020 through programmes including Shovel Ready and Nature-Based Solutions but noted future funding availability was uncertain in the current economic climate.
Sarah Curtis is a news reporter for the Northern Advocate, focusing on a wide range of issues. She has nearly 20 years’ experience in journalism, most of which she spent reporting on the courts in Gisborne and the East Coast.