The week I started my new job I got to attend the annual meeting for our research group at Wairakei, just outside the town of Taupo on the north island. It is a short flight from Christchurch, made even quicker by the fact that you don’t even need to do security for these small flights, you just walk across the tarmac from the main terminal and climb on board. About an hour and a half later we started our descent into the nearby town of Rotorua, the captain didn’t need to announce our arrival as the smell of sulphur from the geothermal features in the area started to permeate the cabin as we made our way down to Rotorua airport.
I spent most of the trip attending the annual meeting, learning more about my new role and making sure things ran smoothly. However, one afternoon a couple of co-workers and I were able to sneak away for a couple of hours to explore the area. Our first stop was the nearby Huka Falls, the falls themselves are only about 15 metres (50 feet) high, but the colour and volume of water still makes them quite striking.
Although the area is named for the falls, the Waikato River here actually goes through a narrow basalt channel for about a hundred metres (330 feet) before reaching the falls. As the water is funneled through this narrow channel you can see all the different shades of blue and turquoise which change constantly. We were lucky when we visited and the water level was quite high so that we could hear a constant roar of the water whenever we got close to one of the lookouts.
After visiting the falls we continued on into the small town of Taupo and had a quick walk along the lake front. Lake Taupo is the largest lake in New Zealand and has formed in the caldera of the Taupo volcano. Although the lake is almost 50 kilometers long (29 miles), we were able to make out the summits of Mount Ngauruhoe and Mount Ruapehu in the distance (both are actually active volcanoes), despite their snow covered peaks blending into the clouds.
We had a little more time before we needed to get back to the annual meeting and so we stopped by Craters of the Moon to visit the geothermal features.
The entire area was full of steam vents and other geothermal features. As we followed the board walks around the area we could feel the humidity increase as the hot, humid air from the steam vents (fumaroles) drifted past us.
The were two large mudpots in the geothermal field, and although they were bubbling away slowly, surprisingly they didn’t have a strong sulphuric smell that is often associated with geothermal features.
The entire geothermal area around Taupo is constantly changing; in the 1950s the construction of the nearby Wairakei Power station reduced the pressure in the hot water systems below the earth’s surface. Since the 1950s the total heat output at Craters of the Moon has gone from about 40 Megawatts to as much as 420 Megawatts in the middle of the 1960’s although it has reduced down to around 200 Megawatts today. It is interesting to see how much these areas are changing in a relatively short space of time.
After finishing the loop around the geothermal we headed back to our hotel to get back to work. We were only gone for a couple of hours but it was a great break and a chance to see some very different places.