Chapter 1 Inundation & Devastation - Introduction and background information regarding Cyclone Bola throughout New Zealand.
Chapter 2 Disintegration & Destruction - The collapse of the Wairoa Bridge and all Service Utilities.
Chapter 3 Survival & Tragedy - The conditions and heartbreak in the first week after Cyclone Bola.
Chapter 4 Isolation & Transitional - Initial response to Wairoa's total isolation from the outside world.
Chapter 5 Provisional & Interim - Alternative transport routes provided to access both Wairoa north and south.
Chapter 6 Restoration & Construction - The planning and contruction of the new High Level Wairoa Bridge.
Chapter 7 Unification & Celebration - The Opening of the new Wairoa Bridge and the unity of the Wairoa township.
Chapter 8 Memories & Recollections - Personal stories and recollections contributed by our Readers.
Chapter 6 - Restoration and Construction
While temporary measures were being set in place, designing of the new Wairoa High Level Bridge had began. The river had a maximum depth of around 15 metres in the central channel. The bed and banks were and are very silty and susceptible to scouring and slumping during any sort of flooding. The water level can fluctuate depending on the tides, the backup of water and whether the bar (river mouth) was open or not. The new bridge needed a greater span between the piers to avoid debris build up. An improved pier design that would not block the debris so easily. High enough allowing for the clearance of flood waters but descending on both sides to meet up with the State Highway and of course it had to look good, it was in the center of town.
The design chosen comprised of six 32metre span, post-tensioned, notched I-beams on flared, single column piers, each with four 900 mm diameter raked piles socketed 3 metres into the riverbed. This structure's much longer spans would reduce flow obstruction and a reasonable vertical alignment for the approaches. The new Wairoa High Level Bridge was to be built high, strong and aesthetic in appearance. [3]
Plans for the new bridge were released on the 18th of May 1988. Preparation for the new bridge site was underway. Contractors were enlisted, materials were ordered, machinery was transported in and Wairoa was taken over by 4 cranes, bulldozers, diggers, steamrollers, concrete mixers, forklift and drilling rig. The plans and designs were double checked and checked again. McDonnell Dowell Contractors of Auckland gained the construction contract for the bridge and work began in October 1988. In November 1988 basic ground work began.
Firth of Napier won the contract to supply 2600 cubic metres of concrete for the bridge. A plant was established off Kaimoana Road and it was there the mix was prepared. Castcrete Concrete, owned locally, was in charge of transport. A temporary work Jetty was built across the river which was completed in February 1989.
Above is the temporary Construction Platform, also known as the Works Bridge, being built. From what we can ascertain this bridge was washed out twice. The first time in the May 1989 after becoming banked up with branches and debris. This delayed work on the main high level new bridge as the Construction Platform had to be repaired. This was done and work continued on the Main Wairoa Bridge.
The second time, however, in August 1989 when the force of the water current plus the build up of debris was too strong, the Construction Platform was basically demolished and not worth repairing. Thankfully the Works Construction Platform was not needed anymore and the remains of the bridge were dismantled and removed. Above is a photo of the Construction Platform before it was swept under. You can clearly see the build up of debris and the reason why such a small structure was unable to withstand the elements.
Works carried out initial investigation work across the site using a drilling rig. The river bed comprised of 30 metres of soft silt and sands overlaying a bedrock of sandstone. The bridge's 32 metre spans would give high pile loads so it was necessary to pound the piles down into the bedrock.
In November, basic ground work began in preparation for the embedding of the piles. There was massive boxing and concreting of the piles, pile caps and the columns followed by the pouring of concrete which began on the 13th of December 1988.
In January 1989 the I beams were under construction along Kaimoana Road. The beams were prepared in batches of 5 and transported along the Rangiahua route to the south side. By late February the first abutment was ready for concreting followed by the I beam set in place. On the 13th of September 1989 the last I beam was lowered and the gap in the bridge filled.
The bridge was completed in November 1989 ready for traffic. The water and sewage pipes clamped either side of the bridge were completed and ready for reconnection
The construction of this new bridge was not built without casualty however. Two workers lost their lives on site during the construction in 1989. Local Wairoa man Sheik Tapuae Aranui and Lawrence George Sayles. A memorial stone sits on the inside of the Wairoa Bridge with a commemorative inscription to honour both these men who died accidentally.
Works Civil Construction were contracted to build the bridge's approaches and the design and planning commenced in August 1988.
The Wairoa Community watched in anticipation as preparations were made for the new bridge to be completed. Soil and metal had been trucked in and both ends had been built up to match the increased 3 metres height of the new bridge. This affected two major intersections in Wairoa with all eight roads altered to allow a gradual incline onto the high level bridge. The town side has three main roads linked to the bridge with the ring road system plus two one way side roads to allow access to the shops below. The north has two roads linking up with the bridge and one side street access. The photo above clearly shows how much higher the new bridge was to be and also how high the roads needed to be built up. All new pipes were laid underneath and along Paul street to carry both the town water supply and the sewage from the north side. The read was laid and the curbing cemented. From June 1990 onwards, work began on the remains of the old bridge which was broken up and carted away from the south side.
Six businesses on the Marine Parade and Paul Street had been relocated as their shops were demolished to allow a Round-about system to be built allowing access from the south. Hornby's Chemist on the corner was relocated to Clyde Court and the old Hornby's demolished. Willy Weavers closed and was demolished likewise The Gift Shop, an empty dairy, Clarks empty Garage and The Gaming Centre.
On the north side, Dr Chilvers was relocated to Clyde Court, the Deluxe Mobile Service Station was relocated a block further north along Bridge Street. The old Deluxe building had been demolished likewise the empty dry cleaners building next door. The removal of these buildings had allowed the necessary space for the traffic coming off and on the new bridge.
The community had watched as the structure of the new bridge took shape. The structure was solid, high, wide and seem to tower over their small town. This enormous metal and concrete structure raised the question on the lips of many, 'have they gone too far this time'. But the 'powers that be' knew what they were doing. Once both the on and off accesses were built up and the ring road system in place, the increase in height did not look so daunting.
Because of the incline along Paul Street heading up to the ring road a pedestrian concrete tunnel had to be build to link up the footpath from East Marine Parade to West. The photo above shows this in progress. The completion of both approaches and the tunnel were towards the end of November and emergency traffic was allowed on the bridge. The last of the water pipes were laid. The water supply was turned off and the last of the pipes were linked to redirect the water through the new system. At the same time the sewage was also re routed through the sewage pipe clamped on the other side of the bridge. The water was turned back on and after 21 months road workers and onlookers watched one of life's essentials pour across the side of the new bridge, under the Round About and down Paul Street heading towards the tanks on Tawhara Hill.
The lighthouse was relocated slightly and elevated and a footpath through a rockery was built with outdoor chairs facing a great view of the Wairoa River as above. There is a whaling Pot bottom right of the rockery and an old Post Box up beside the main street footpath along Marine Parade. Many miniature trees and bushes were planted and now years later this corner is extremely pretty.
Take another look at the photo above, see how high up the Wairoa Lighthouse is compared to the water level in the river below. Then go back up to the photos of the Lighthouse above surrounded by water, this will give you an idea as to how high the water rose over the bank.
A children's Playground was built and a picnic area as you can see from below on the left. The town was smart and tidy once again.
References
1. Wikipedia, The Free Encyclopedia.
2. Te Ara, The Encyclopedia of New Zealand.
3. The Wairoa Star.
4. The New Zealand Herald.
5. Television New Zealand Archives.
