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| 1966 Aerial view of the Waioeka River as it meanders across floodplains, is joined by the Otara River at Ōpōtiki, and makes its way to the Bay of Plenty through the narrow harbour entrance and sandbar. Source: LINZ. Retrieved from: www.retrolens.nz (2018). |
The main harbour mouth of Ōpōtiki is formed by the Waiokea River, after it has been joined by the Otara River shortly before exiting to sea where longshore ocean currents fed by a continuous supply of sediment have formed the familiar sand-bar. Like many settlement sites in New Zealand, the area around the mouth of the Waioeka River and its surrounding floodplains was considered favorable for trade and transport opportunities, and fertile ground for agricultural production.
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| The 825 sq. km. steep, bushclad, and high rainfall country of the Waioeka catchment. Sorce: MfE and GoogleEarth (2018). |
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| High in the steep ranges many creeks and tributaries join together to form the Waioeka River and begin their journey to the sea at Ōpōtiki. Source: LINZ. Retrieved from: data.nzpam.govt.nz (2018). |
The Waioeka River has it's headwaters high in the steep and bush-clad Raukumara Ranges, and is fed by a catchment of 825 sq. km. The steep ranges are prone to intensive rainstorms, which can cause high-energy flood events able to move large amounts of gravel, debris and sediment. The seemingly solid looking ranges are formed from 150 million year old sedimentary rocks composed mainly of greywacke and argillite, which may be brittle and sheared due to tectonic forces and prone to slipping. In fact the Waioeka gorge represents two opposing forces, permanently locked in a struggle for equilibrium. The depth and sheer sides of the gorge are testament to the erosive power of water, especially when loaded with corrosive sediment and gravel. However the surrounding mountains and gorge are also shaped by relentless tectonic forces, thrusting this distorted and folded land upwards at a rate of approximately 6mm a year. Every rise in the land will be met by the river expending energy to return back to sea-level. After exiting the gorge, the river follows a meandering path across level flood-plains formed by thousands of years of sediment deposits from past flood events.
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| Above and below: The erosive power of sediment laden water as it carves a gorge through the 150 million year old greywacke rocks forming the ranges. Source: Author (2016). |
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| 1944 aerial view of the confluence of the Waioeka and Otara rivers with the township of Ōpōtiki located on the floodplain and the sandbar clearly visible.Source: LINZ. Retrieved from:www.retrolens.nz (2018). |
To go back in time prior to the arrival of humans in this landscape picture a very different landscape from the one we look out on today. In hollows between dunes surrounding the river mouth rainwater would have collected and formed small wetlands. Larger wetlands and their uniquely adapted plants such as rushes, toe toe and flax would have formed on the river flats, and moisture loving trees such as pukatea and kahikatea would have formed a spectacular backdrop. Rivers and their tributaries would have been bounteous with native fish and eels, and wetlands provided a haven to bird species in numbers we can only imagine today. Where today floodplains are crisscrossed by fences and drains forming paddocks, in the past they would have been thick with flax, manuka, cabbage tree, kahikatea and other plants adapted to regular inundation.
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| Stream banks clothed in wetland plants and hills cloaked in native vegetation. How much of the Eastern Bay of Plenty would have looked at the time of arrival of the first humans. The low species at front is Bolboschoenus fluviatilis (kukuraho, or marsh clubrush), the taller species is Typha orientalis (Raupo). Both are species found in freshwater rivers and lakes, and also saline estuaries and saltmarshes. Source: Author (2018). |
For centuries prior to European settlement Māori had utilised the resources and transport opportunities afforded by the rich landscape shaped by these rivers. The river was named Waioeka (Waters of the Weka) due to the abundance of this well-known cheeky bird in the vicinity of the river. Archaeological evidence, the remains of Māori earthworks, and oral history tell us this area of coast from Ohiwa Harbour in the west to Opape in the east was densely populated, and given the access to marine, freshwater, and forest resources, and the outlook over this valuable stretch of coastline, this comes as no surprise.
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| Above and Below: The cheeky bird that gives the Waioeka its name, The North Island weka (Gallirallus australis greyi).The Eastern Bay of Plenty is a significant population of the bird, but is subject to fluctuating population levels. Current numbers are growing. Source: Jeremy Painting (2018). |
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| The weka is a species of flightless rail, endemic to New Zealand. One of its favoured habitats is swamps and wetlands, but it can also be commonly seen in paddocks and crossing roads. It was a favoured food source for Māori, mainly because of the ease with which it could be caught using a lure and snare. Source: Shaun Lee (2018). |
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| Māori midden (shellfish dump) exposed by erosion on top of coastal terraces at Waiotahi Beach. Source: Author (2017). |
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| Detail from above, showing layers of shellfish. The group of large rocks towards the right of the photo are likely to be hangi stones. Source: Author (2017). |
Inland settlements tended to be near rivers, while coastal settlements took advantage of harbours and river mouths. Where the present day town of Ōpōtiki sits at the confluence of the Waioeka and Otara Rivers was a large settlement called Pā Kowhai extending along the river banks. This was also a commonly used name for the area occupied by the Ōpōtiki township and surrounds prior to establishment of the European settlement. Large fishing camps would have been established at coastal locations taking advantage of the bounty of the sea. Wetlands were recognised as important for filtering water; a nursery for fish, frogs and wetland birds; and they also provided Māori with building resources such as toetoe and raupō. The river was also used to transport suitable large logs as close as possible to the construction site of wharenui.
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| Raupō (Typha orientalis), a wetland plant and widely used resource by Māori. Roots were eaten, pollen was made into a bread, and leaves and stalks had a multitude of uses in building. Source: Author (2018). |
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| Catching a weka with a food lure and snare. Detail of painting by William
Fox "In the Aglionby or Matukituki Valley, looking into the Otapawa. 20th Feb. [1846]". Source:
Alexander Turnbull Library (2018).
Fox, William (Rt Hon Sir), 1812?-1893. [Fox, William] 1812-1893 :In the Aglionby or Matukituki Valley, looking into the Otapawa. 20th Feb. [1846]. Ref: B-113-008. Alexander Turnbull Library, Wellington, New Zealand. /records/23009335 |
The river estuary would have provided a safe shelter for waka, with gently sloping river banks providing suitable landing places. Pā sites and their associated settlements were required to have access to waka launching places, suitable sites for eel weirs and fishing. The importance of this waterway was not only limited to the river itself, but also to its numerous tributaries. These deliniated tribal and hapu boundaries, and served as an important transportation network. River waka were fashioned from an appropriate tree, allowing accommodation for up to four persons and their goods. These traditional river waka were still being used to travel upriver and downriver at the time of European settlement. A traditional river waka can be viewed at the Whare Taonga, on the top floor of the Ōpōtiki Museum. While the areas around the harbour mouth and coast were densely populated, habitation was not limited to these areas, with several settlements further upstream.
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| Traditional river waka recovered from farmland and on display at the Whare Taonga, Ōpōtiki Museum. Source: Whakatōhea Research and Archives Trust (2018). |
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| Above and below: Māori settlement at Waioeka. Date and photographer unknown. Source: Whakatōhea Research and Archives Trust (2018). |
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| Early 1900s view of the Waioeka River at Ōpōtiki. The canoe on the right is a traditional Māori dug-out design, still widely used for a period after European settlement. Source: Alexander Turnbull Library (2018). Ref: 1/2-001308-G. Alexander Turnbull Library, Wellington, New Zealand. /records/22834973 |
The earliest European settlers were missionaries, traders, and whalers. However, it was conflict over land in the 1860's that provide the impetus for development of the town as a military garrison. After hostilities ceased a nervous government decreed the township a military settlement, and confiscated all the coastal lowlands and hill country overlooking the lowlands. Access to freshwater and estuarine fisheries was severely disrupted and in some cases denied all together. From this time on the town grew fairly rapidly, with fertile land on the river flats drained to produce maize, potatoes, and wheat. No regard was given to the importance of wetlands in filtering sediment from water and mitigating flood flows from the river, they were considered as valuable only if drained, cleared, and brought into agricultural production. Drainage and clearance was undertaken with a zeal repeated throughout the low lying plains of the North Island. Ironically it was the sediment built up on floodplains after thousands of years of flood events that made this land so desirable once it had been drained, but in order to bring this land into economic production, the natural river processes that had taken place over thousands of years were tamed and subdued.
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| While larger wetlands were drained using machinery, most wetlands around Ōpōtiki would have had drains cut by hand such as this one on the Rangitaiki wetlands in 1910, and flax would have been cleared by hand. Source: T. Thorne Seccombe (1910). Sir George Grey Special Collections, Auckland Libraries, AWNS-19100721-16-4. Retrieved from Auckland Libraries (2018). |
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| Machinery was used to drain 90,000 acres of shallow water wetlands around the Rangitaiki River, activity that was being repeated all over the North Island. Source: Auckland Weekly News (1914). Sir George Grey Special Collections, Auckland Libraries, AWNS-19141126-49-2. Retrieved from Auckland Libraries (2018). |
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| "Bringing nearly 90,000 acres of swamp lands into occupation and
productiveness: The canal, which provides a quick escape to the sea of the waters of the Rangitaiki River, Bay of Plenty." Source: Auckland Weekly News (1914). Sir George Grey Special Collections, Auckland Libraries, AWNS-19141126-49-1. Retrieved from: Auckland Libraries (2018). |
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| Clearing of bush in the high country of the Waioeka catchment contributed to increased sedimentation and run-off, effects felt downstream from the earliest days of settlement. Source: A. Macquaters/Auckland Weekly News (1907). Sir George Grey Special Collections, Auckland Libraries, AWNS-19070912-3-2 (2018). Retrieved from: Auckland Libraries (2018). |
According to the BOPRC, the Bay of Plenty has lost 97% of its wetlands in the last 150 years, with only 1% of an original 40,000 hectares of shallow wetlands remaining on the Kaituna, Waihi, and Rangitaiki plains. While we do not have exact figures for wetland loss associated with the floodplains of the Waioeka and other rivers in the Ōpōtiki area, it is likely to have been considerable given the appetite for productive farmland. However, with increased production came the need for reliable transport, which saw the development of an important shipping industry moving both freight and passengers in an area not well serviced by road and rail till the mid-20th century.
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| Shipping Maize at Ōpōtiki, East Coast, Auckland. Source: J.Mann (1901). Sir George Grey Special Collections, Auckland Libraries, AWNS-19011219-7-1. Retrieved from: Auckland Libraries (2018). |
One of the greatest assets for the town of Ōpōtiki as it was developing was its situation on a navigable harbour formed by the estuary of the Waioeka River. Additionally this area was poorly served by road and rail at this time, so sea-freight was the most viable method of transport for goods coming into and out of the district.Taking advantage of this need, a number of ships were owned and operated by the Whakatōhea iwi between 1840 and 1860. Over time Ōpōtiki became one of the major ports servicing the Bay of Plenty, for freight and passenger services to and from Auckland. In 1902 a service between Auckland and Ōpōtiki took 19-24 hours, compared with 3 days overland. However from the earliest days of shipping factors such as sedimentation in the channel and the shallow harbour entrance with a sand-bar proved challenging. At times tenders were used to load and unload freight when larger boats could not cross the shallow entrance, and in 1904 a new wharf was built which allowed the berthing of larger vessels. Passenger services ceased in 1923, while freight services continued until the late 1950s.
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| Ship stranded on the sandbar at entrance to Ōpōtiki Harbour, 1906. Photographer unknown. Source: Ōpōtiki Museum (2018). |
While the river was seen as of benefit to the Ōpōtiki community for transport and as a drainage channel for removing excess water from drained areas, in times of flood it came to be seen as a violent and destructive force the community strived to bring under control. The erosive power of water was able to wash away farmland near the riverbanks, with erosion and flooding of the Waioeka and Otara rivers of concern since the beginning of European settlement in Ōpōtiki. In many cases individual landowners had undertaken their own works, however after flooding in 1957 and 1958 local authorities undertook a comprehensive flood protection scheme, which involved willow protection of eroding banks, straightening of meanders, clearance of a floodway, and river training prior to the construction of stop-banks. These works were well underway when the worst flooding in recorded history struck Ōpōtiki and surrounding areas in 1964, causing the work to be fast-tracked and completion of the flood-protection scheme in 1967.
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| Above and below: Aerial views of Ōpōtiki following the 1964 flood event. Photos were taken six hour before water reached its peak, at 1.5 metres deep in the main street. Source: Gisborne Photo News (1964). Retrieved from: photonews.org.nz (2018). |
In these great flood events the water collects in the catchment of the Waiokea river, joins the river as it drops 25 metres through the sometimes vertical walls of the Waioeka Gorge. A road of sorts joined Ōpōtiki with Gisborne through the gorge by 1929, but travel was arduous over the largely unsealed muddy track that had to ford unbridged streams and was subject to frequent landslides during rain. In 1950 the government announced it would upgrade the road, with the final cost of the 40 mile stretch through the gorge £2 an inch ($4 per 2.5 centimetres) or £120,000 a mile ($150,000/kilometre). The steep sided channel carved through the brittle and sheared rocks of the gorge presented numerous engineering challenges.
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| Carving a road out of shear rock face during construction of the highway through the Waioeka Gorge. Source: Gisborne Photo News (1959). |
One of the most significant challenges was a 50 metre high bluff that had to be dropped into the river, allowing the river channel itself to be moved by 12 metres and providing a platform for the road to be built on. In an incredible feat of engineering, bulldozers had to be lowered down on steel ropes to clear the debris, and it is tragic that three men died during the construction of the gorge. From the earliest days of travel through the gorge the road has been plagued by frequent slips due to the brittle and sheared nature of the rocks, and the high rainfall in the area. The most significant of these was a large slip in 2012 that closed the road for 26 days. Despite the feat of engineering that the road through the gorge represents, it does not pay to take it for-granted, with regular slips and debris falls closing the road. While the steep slopes of rock forming the gorge may appear "solid as rock", they are in fact brittle and sheared due to tectonic forces lifting the rocks and with many joints and cracks for rainwater to seep in and weaken the slopes.
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| Aerial view of face of 2012 slip that closed the gorge road for 26 days. The slip actually occurred over two days, with the second slip occurring the day after the first one when workers were inspecting the slip. Source: NZTA (2012). Retrieved from: http://www.gdc.govt.nz/waioeka-gorge-update/(2018) |
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| Detail of above, showing vegetation and thin layer of soil overlying brittle and sheared bedrock. Soil and vegetation is prone to destabilization, especially when water decreases friction between bedrock and overlying soil. |
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| Road washout on State Highway 2 by Waioeka River, high flows during Cyclone Debbie in 2017 have eroded the bank and undercut the road. Source: Liam Clayton, Gisborne Herald (2017). |
On this journey with the Waiokea river through time, and from its headwaters in the Raukumara Ranges across the floodplains and to the harbour mouth at Ōpōtiki we can see how the river has shaped the land it travels through and across, how it has shaped the communities that have lived by its banks and on its floodplains, and how those communities have left their mark on the river and its landscape. And now another momentous change is in store for the river, with the development of a new harbour accessible through a permanently clear channel, which may be the beginning of a new chapter in the history of Ōpōtiki and the Waioeka River.
Explore Artifacts and stories of Whakatōhea and Māori life in
the Ōpōtiki region at the Whare Taonga, top floor of the Ōpōtiki museum.
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| Available for purchase from the Ōpōtiki Museum. |
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