How the Bay will feel the heat As I reported in the last edition of BayBuzz (Only a Chance to…
Keith Newman finds coastal campaigner Larry Dallimore as persistent as the current that perpetually sweeps gravel northward around Hawke’s Bay. With millions of public dollars and a valuable coastline at stake, why aren’t councils responding to him?
Larry Dallimore is a stone in the shoes of Hawke’s Bay bureaucrats, engineers and councillors. They wish he’d stop pestering them about the dynamics of coastal erosion and his proposed Westshore seawall.
Dallimore, who has lived at Westshore for over 30-years, is first to admit that people’s eyes mostly glaze over when he tries to explain the coastal processes that are unique to Hawke Bay and the simple construction measures that could stop erosion and save councils millions of dollars.
Although the retired contractor doesn’t have academic ABCs after his name, he’s got old school, hands-on credentials, having worked for all the local authorities over decades constructing reclamations, seawalls and breakwaters.
Dallimore’s often verbose attempts to deliver reports on how he sees things seem to get him into deep water, particularly when he advocates the use of local limestone for coastal protection, rubbishes the 2007 Komar ‘shoreline erosion’ report and criticises the tendency for councils to ignore the flexibility in the National Coastal Policy Statement.
When he’s not playing golf or fishing, Dallimore has made it his business to keep a watchful eye on decisions relating to Westshore erosion, which extends 2.8km from the headland at the Iron Pot (Whakarire Ave) to just past the end of Westshore Esplanade.
He’s attended all the meetings about the Napier City Council’s proposed 155 metre breakwater at Whakarire Ave and remains astounded at “the nonsense some people come up with” and the reliance on out-of-town experts to over-ride previous reports.
His current pet peeve is Napier mayor Barbara Arnott’s “fantasy” that if you add a new breakwater and keep renourishing with gravel, the sand will eventually come back to beaches north of the Port of Napier.
Dallimore wonders why Napier City would rather pay millions for ineffective beach renourishment and a new breakwater than have an open discussion around his concerns, and the possibility his seawall proposal might have merit.
He reckons private property, Kiwi Beach public toilets and large areas of reserve in the erosion zone could be saved through extra strengthening to existing rock protection. By adding a permanent rock seawall the Westshore Surf Club and the entire beach reserve would also be secured, saving millions on renourishment costs.
Dallimore is convinced breakwater extensions at the Port of Napier, and the deepening of the shipping trench which gathers northbound coastal sediment, have been major contributors to Westshore erosion since the 1970s.
Rather than Napier ratepayers footing the bulk of the cost for protection works and renourishment, he wants to see the Port of Napier and its 100% owner HBRC taking ownership for the man-made problem and the solution.
The earliest attempt to protect Westshore was in 1987, when a badly executed renourishment plan, using incompatible material sourced from the estuary, turned the beach into a muddy mess. Then Beca Infrastructure designed a shingle bank with a “moderate repose” but with each swell Dallimore says beach access becomes impossible.
The renourishment plan is supposed to include dredge droppings brought in from Pacific Beach, Marine Parade, which would otherwise end up in the shipping lane and be removed at a cost of over $30 m3. However the dredges can’t get close enough to the Westshore erosion zone.
In fact, most of the spoil gets washed further north to Bay View where, according to Dallimore, they’re appreciating the improved surfing, a wider beach and greater demand for properties.
Overall, he says, the $4 million Westshore nourishment programme is a costly waste of time, made worse by the use of increasingly smaller pebbles from Pacific Beach that are essentially rejects from years of shingle plant screening. “It’s an engineering myth that you can put pebbles on a sandy beach and expect them to stay there or that you will eventually restore that beach.”
Dallimore says similar nourishment issues plagued the beach at Whakarire Ave, where material was simply swept north over a seven year period. NCC built a rubble and limestone wall in 1994 to reclaim and protect the land, but it funnelled wave energy to the southern side of Westshore worsening the erosion.
NCC now plans to mitigate that with the $4 million breakwater project, plus increasing the height of the seawall and re-profiling the backshore, in the hope it’ll create a new sandy beach on top of a reef, something Dallimore struggles to comprehend.
He believes the Beca Infrastructure designed breakwater will only funnel even more wave energy northward into the erosion zone. He tried to explain why it won’t work in a 30-page ‘discussion note’, then a further 34 page addendum to Napier councillors but claims nothing was discussed, explained or refuted.
Dallimore wanted a public debate with himself and the Beca engineer answering seawall versus breakwater questions. That seemed acceptable until a point of order was raised, essentially stating “we can’t have our paid consultants being quizzed by our residents”. A seminar was then held but he was barred from attending.
He began discussing the issue with the Beca engineer reviewing his report, but that dialogue was shut down by Napier mayor Barbara Arnott, who apparently insisted it was costing the council money and therefore ‘unacceptable’. He could never quite figure that one out.
Although issues about length are holding up the breakwater consent process, Dallimore reckons it won’t get past submissions from surfers who believe it will ruin their surfbreak, HBRC interpretations of the coastal policy, and opposition from environmental groups.
That may swing the focus back to his 2.8km rock seawall for Westshore. However, Dallimore worries that even if it is considered consentable, it may be subject to artificially inflated costs. The case in point is the “over designed and extravagant” repair job on the badly maintained Hardinge Rd seawall.
Napier City contracted HBRC to repair a 45 metre section of the seawall; it used filter cloth, crushed concrete, limestone rubble and a 1.5m layer of limestone boulders costing $135,000 or $3000 per metre.
Dallimore reckons a simple ‘rip rap’ seawall with a base of graded rubble then a rock armour layer would have been adequate at less than half the cost.
During the 1970s vast quantities of rock rubble were removed from the Hardinge Rd foreshore reserve for retaining and reclamation work at Napier Port, along with “countless truckloads” of sand and gravel from the once endless supply at the Perfume Point Pit.
Gravel movement had slowed when the shingle pit closed around 1980 and it was no longer piling up on the beaches. At the time no one seemed to connect this to developments at the Napier Port.
In hindsight, Dallimore believes this helped starve the supply to the Westshore Beach. Not satisfied with the reports that fingered the Port breakwater and the deepening of the shipping channel as major contributors, the Port of Napier, its 100% owner HBRC, and Napier City Council, commissioned Dr Paul Komar to review Beca’s breakwater studies and another 80 or so historical reports.
Komar, a retired oceanography professor from Oregon State University, began work in 2003 and delivered his “Hawke’s. Bay Environmental Change, Shoreline Erosion &. Management lssues” report in January 2007, identifying the 1931 earthquake as the major culprit.
Dallimore says there was no science to back that assumption or examples of comparable events in other parts of the world. A couple of lines borrowed from coastal expert Dr Jeremy Gibb stated erosion began at Westshore in 1962. “It’s a myth. I have photographic evidence and a good memory that it didn’t start until the late 1970s.”
He remains puzzled at Komar’s conclusion that the Port of Napier breakwater has reduced erosion losses, sheltered Westshore from storm waves, halved wave heights and bought relative stability to the beach.
But what really gets Dallimore is the almost emotional: it’s “time to put aside the placement of blame on the construction of the Port’s breakwater” and get on with improved recreational development of the shore. The beach has continued to decay.
He says it appears Komar’s conclusions are based on the breakwater as it existed about 1980 as there’s no mention of the deepening of the shipping channel and other major impediments to the flow of beach replenishment. “He then ends up asking people to stop blaming the Port and get on with it, like some kind of psychologist.”
Dallimore irreverently asserts that in Hawke’s Bay the Komar report has more power than the Treaty of Waitangi. “It’s the defining document. Everyone keeps referring back to it but if you read it carefully you discover how much has been missed and realise whose interests are being protected.”
Dallimore, who spent 23 years as Hawke’s Bay Harbour Board’s preferred contractor, claims decades of removing shingle from the region’s rivers has contributed to Hawke Bay’s man-made erosion.
He says millions of cubic metres of shingle were removed with full knowledge of the then Hawke’s Bay Catchment Board — that extraction continues today under its successor the Hawke’s Bay Regional Council (HBRC).
“The big stone was taken out for railway ballast and chips for roading then the small stuff was dumped back in the river to go out the river mouth to Awatoto.”
There used to be “beaches of shingle and stone” on either side of the Tutaekuri River. “We’d be in there with a front-end loader removing it at the direction of the Catchment Board. They thought we were helping them take the meander out of the rivers but while we were doing that we were also lowering the gradient of the riverbed.”
Today, he says, the Awatoto plant can’t get stones large enough for shingle chips which, along with sand, are the pay dirt of any shingle company. “They have to get it from the river system and that’s continuing to starve the supply to Hawke Bay.”
Dallimore’s got no issue with the Port of Napier or Awatoto going about their business, but suggests they need to take some responsibility for the consequences of their actions.
Seawall matter of gravity
Which brings us back to the Westshore seawall. Dallimore thought he’d try and help Napier City with some ideas on wall design back in 2009. That’s when his disillusionment with the public process began.
“I got labelled a self-styled expert by the Napier mayor before she even read my assessment and that’s where the disdain started. I’ve been shoved around ever since.”
Essentially he says the best way to reduce wave energy is dissipation and gravity. “An affordable ‘rip rap’ seawall would be an ideal long term solution, causing uplift while the rocks created white water to filter down to reduce the backwash.”
He says local limestone has been successfully used for seawalls and reclamations for decades; he supplied 352,000 tonne of rock from four different quarries over 23 years for different projects.
For a time, Dallimore had much higher hopes for the Westshore seawall; a proposal was put forward in 1998 but dashed when the National Institute of Water and Atmospheric Research (NIWA) recommend imported rock be used.
The project cost soared to $60.4m with annual maintenance of $350,000 — and with it the myth that local limestone rock is not suited for coastal construction. Beca Consultants recommended rock from Tauranga and New Plymouth be used for the Whakarire Ave breakwater at $90-$100 a tonne for transport alone. They admitted in 2010 that they had not investigated rock from two local quarries.
Dallimore says advice presented to NCC by both NIWA and Beca “was bullshit then and an utter disgrace now” adding unnecessary cost to projects. “We’re in one of the most prolific limestone areas in the North Island — it’s lying in the valleys up the Taupo Rd — you don’t even have to dig it out and you don’t need resource consent to extract it or place it.”
Meanwhile the war of words continues. Dump the Whakarire Ave breakwater, says the lone coastal crusader, and concentrate on repairing and strengthening existing limestone rock protection that has not been maintained for decades.
And he urges the HBRC and Port of Napier to step back from their fortressed positions and take some of the pressure off Napier ratepayers by picking up part of the tab for ongoing renourishment and protection work.