Omanawa Falls is still packed with trespassers, with dozens of people at a time visiting the dangerous spot despite an official closure for safety reasons.
Tauranga City Council parks and recreation manager Warren Aitken said some people had tried to get past security guards hired to support contractors working in the tunnel at Omanawa.
"The security guards were there for three-and-a-half days, which was the duration of the project. It was effective in deterring people, most of whom were not locals."
However, Omanawa resident Warren Dawson said that during summer the number of trespassers accessing the falls outside those days had been greater than he expected. The small rural road that backs on to the access way had been "absolutely jam-packed" with up to 60 cars parked by the entrance.
"It's gone nuts," he said. "It's unbelievable."
Mr Dawson had warned of the falls' safety after multiple rescues took place, but the official closure had been to no avail.
On one recent day he had stopped three carloads of people from entering, telling the occupants that they were entering private land.
"The word is out there," he said. "It's a beauty spot and it's no problem to find. But it's just dangerous. Very dangerous."
Late last year, traveller Ailis O'Neill discovered Omanawa Falls through a website about North Island waterfalls. He said that he had to hang on to tree roots while climbing down to the falls.
"For me it probably was one of the most dangerous things I've ever done. The way down is pretty much vertical."
For years the Tauranga City Council, which owns the underground power station and its access down from Omanawa Rd, has unsuccessfully tried to stop people reaching the falls.
Gates and fences erected by the council were no barrier to determined visitors.
Last October a 32-year-old French man was rescued when he fell 10m down the cliff, catching a tree which prevented him from falling 40m further to the rocks below.