Wainui Stream culverts are filled with woody debris following last week's storm causing locals to worry about the hazards of the debris on infrastructure and beach safety. Photo / Paul Rickard
Woody debris has once again filled culverts in Gisborne’s Wainui Stream after last week’s storm - a build-up being described as “a lot worse than Gabrielle”.
It comes just months after a group of local surfers cleaned up the area, removing debris that had accumulated from previous storms.
Surfer Jonas Te Aho, who helped lead the last clean-up with his surf crew Te Moananui a Kiwa, said it was the worst build-up he had seen.
“Council might contract someone to clean up the beach, and then it’s back to where it is now.
“We live right next to the stream, but we’ve also got neighbours who are more low-lying than us having the debris washing up over on to their lawns and sections.
“It must be a bit scary for them, especially for the older ones.”
In a Gisborne Herald article from 2015, the culverts being clogged up by slash at the mouth of the Wainui stream was described by a local as “a relatively new issue”.
Council environmental monitoring and science manager Dr Amber Dunn said woody material had always washed up on Wainui Beach in varying amounts.
“This woody material will occupy and gather in the lower-lying regions of the beach. This is often around stream mouths or stormwater outlets e.g. Stock Route beach access and School access.
“The swell direction affects where woody material accumulates on the beach and in stream mouths/outlets.”
The latest debris came from a combination of large waves from the southeasterly direction, strong onshore winds and high tides. These forces pushed woody debris up the Wainui Stream towards the Murphy Rd culverts.
“The origin of this wood has not been investigated,” she said.
Wainui local Jennifer Herre Hindmarsh, who notified the council about the mess, said she had not seen it this high since the July 2015 build-up.
“The pile of wood is a danger to public infrastructure, the stream banks and anyone who happens to be here when we have big waves,” she said.
“It doesn’t have to be a storm here. It can be a day like today, where there’s big swells and big waves. They surge up the stream.
“It’s like watching a tidal wave, and you know with all those big logs there, it’ll just push those logs way up.
“If people were standing on the bank unaware... it could be really dangerous,” she said.
Community lifelines director Tim Barry said the council’s woody debris team were visiting sites across the region that were known risk areas to assess the amounts and urgency of each area.
“This woody debris removal will be prioritised and removed when ground conditions allow this work to happen.
“Contractors have put the ‘extreme danger’ signs back up at the city beaches and Ūawa,” he said.
Barry said he expected to have more of an update for the community next week after all assessments had been done.
The council was still in the assessment stage of the total cost for recovery.
“However, knowing what we know so far, the bill will be in the millions and we do not know yet what proportion of this will be spent on the clean-up of woody debris.
“We understand our community’s concern. It’s disheartening for all of us to see the magnitude of the woody debris return that we’d recently cleaned up.”