Why did flooding occur in several Havelock North Streets – some with devastating consequences – during Cyclone Gabrielle?

This is the question a group of residents led by Nicky Solomon want answers to. They have set up a private Facebook page to gather as much information as they can about what happened on February 14^th in streets that include, in particular, Joll Road, but also Tanner, Upham, Toop, Plassey, Von Dadelszen Place, Reynold, St Hill Lane, and Tauroa Road.

“Our ultimate goal is to bring together a thorough and constructive submission to be presented to the Hastings District Council (HDC),” says Nicky.

“We’ve all got different pieces of the puzzle.”

Nicky lives near the top of Toop Street and adjacent to the Mangarau Dam.  It is one of five earth detention dams built above Havelock North in the 1980s to catch surface run-off from Te Mata Peak and surrounding hills, as well as slow down stream water flow, particularly in times of flooding.  The dams are above the Herehere, Mangarau, School, Karituwhenua and Tekahika streams, which all flow or trickle down ultimately into the Karamu Stream Catchment. HDC holds the resource consents for the dams and is responsible for the streams and dams’ maintenance and efficiency.

There have been anecdotal murmurs about the dams and whether they were fit-for-purpose for Cyclone Gabrielle. And there is a history of non-compliance. A Dominion Post article sent to BayBuzz, dated March 2011, reported that “information obtained by The Dominion Post under the Local Government Official Information Act shows Hawke’s Bay Regional Council’s high level of concern about the district council’s failure to maintain the dams”. The article went on to say that the Regional Council sent the HDC a letter advising of “some serious non-compliance with your consent conditions” and noted “that some recommended maintenance on the dams from 2001 had still not been carried out”.

But Nicky Solomon doesn’t want to second-guess the cause of the February 2023 Cyclone flooding as she and other residents gather facts. And she has her own story to tell of Mangarau Dam. On the morning after the cyclone, she and her family watched from their back fence the normally dry Mangarau Dam – the biggest of the Havelock North dams capable of holding 450,000 cubic metres of water – turn into a muddy lake.  “But it never over-topped.  

“It seemed to be doing what it was meant to do,” says Nicky. “But below the dam there was a lot of uncleared debris and logs in the stream and this could have contributed to flooding further down.”

BayBuzz interviewed residents from lower Joll Road in late-February, most still in shock after having had to leave their homes fast filing with water on the day of the cyclone as they waded, waist deep out onto the street and to higher ground. Some told BayBuzz that the flooding only accelerated early on the morning of 14 February after a huge trunk of an old walnut tree, cut down some weeks earlier by Council and left on the bank , was swept into the swollen stream and banged up hard buckling a concrete bridge that usually took residents across it. The force of the tree trunk and the water jack-knifed the bridge and formed a huge dam jamming other logs and debris up against it.

“The water had nowhere to go,” said resident Malcom Wells. “So it turned round.”

Some 50 people have already joined “Cyclone Gabrielle Impact on Havelock North Streams – Fact Finding Facebook page” and are sharing photos and information.

“We’ve all got different pieces of the jigsaw puzzle, “says Nicky. “We need to pull it all together, understand what happened and from there we can meet with Council to make changes and ensure the town is better protected in an extreme weather event.”

If you have information to share and are a resident of one of the streets affected go to https://www.facebook.com/groups/918505022517786/

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