The crew immediately stopped work and contacted Heritage New Zealand Pouhere Taonga Regional Archaeologist, Dr James Robinson, to check it out.
“The workers had partially uncovered a hollowed-out piece of log that looked for all the world like the shape you would associate with a small waka,” says James.
“As we continued to excavate, however, we found that the body of the log had a distinct kink to it which enabled us to rule out the idea that we were dealing with a waka.”
So having ascertained that it was not a waka – not even a particularly ‘wonky’ one – the questions remained; what is this log and why is it lying there, apparently connected to a culvert?
“One of the clues we found was the complete absence of adze marks on the log, which suggests that the feature wasn’t worked by people but rather a result of natural processes,” says James.
Its physical location was also a clue. Originally, the area in Paihia where the roadworks were taking place was swampland behind a raised beach dune. The swamp was eventually drained in the 1800s and infilling has taken place in one form or another here since 1840 to create the residential area of Paihia that we recognise today.
“This process would have been accelerated during the twentieth century with the urbanisation of Paihia and the laying out of a road network,” he says. “Originally the road built up above the swamp appears to have had an open swale drain on each side, and at some point the concrete culvert was installed – probably to provide access to the house. Either by chance or deliberate action the remnant rotted tree was laid in the swale to assist the drainage on that side of the road as a kind of makeshift wooden culvert.”
So how did the tree come to be hollow? And why did there happen to be a half-hollowed tree lying around that was then adapted for use as a culvert?
“We suspect that the log was originally a tree whose interior had rotted away and the weakened remnants had collapsed into the swamp possibly well before humans arrived in Aotearoa-New Zealand,” he says. “The tree had toppled into the swamp, and the bottom half – which would have been underwater was in anaerobic conditions. The lack of oxygen effectively preserved that part of the curved tree remnant while most of the tree left above the water table eventually rotted away leaving what looks like a hollowed-out log.
The working hypothesis is that the hollowed-out log was used as part of a post-World War II, bodgied-up drainage job done on the cheap. “It seems that road workers in the more recent past probably found the log nearby and used it as part of a road drainage solution,” he says. “Such ad hoc and opportunistic use of natural material to assist with road construction is not uncommon in the early history of roading in New Zealand, particularly as roading and maintenance at that time was poorly funded.”
The acid test occurred when the clay fill blocking the concrete culvert was removed and a backlog of water flowed through the pipe and then through the curved wooden log – just like clockwork.
The wooden culvert has been left in place in the ground and the Ventia team have since ran their services above it – leaving evidence of New Zealand’s heritage of parsimonious infrastructure investment intact beneath.
James is awarding the Ventia team full marks for doing the right thing.“Their response was absolutely text book. When they found something that looked archaeological they stopped work and called us, and we were able to determine what it was promptly and get work going again,” he says.
The waka that wasn’t a waka is a really great example of how something that initially appears to be Māori archaeology can sometimes turn out to be something quite different – in this case historic transport archaeology that has now been recorded in the New Zealand Archaeological Association database.
“It still tells a story about our past though – just not the one we originally thought it was.”