The Wai-O-Tapu Thermal wonderland sits just south of Rotorua as part of a scenic reserve.
It is the largest area of surface thermal activity of any hydrothermal system in the Taupo Volcanic Zone and has volcanic activity dating back nearly 160,000 years. The entire area is covered in collapsed craters, boiling pools of mud and water, and steaming fumaroles. It has been described as one of the most surreal landscapes in the world; it certainly felt like stepping into an alien planet at some points! Sometimes, truth really is stranger than fiction.
We started out our trip with a visit to the Lady Knox Geyser. The visitor centre opens around 8:30am most days. It is recommended that you arrive around 9:30 to make sure that you can get tickets and have time to drive the short distance to the geyser, which sits just outside of the park (about 3 minutes from the visitor centre). There is good stadium seating so most places offer a good view. Andrew and I were there early enough to get good seats right front and centre.
The geyser is triggered artificially so that they can draw tourists to it. Without help, it would erupt randomly every two to three days as pressure builds. The geyser has been triggered by soap since the early 1900’s, but it was initially triggered accidentally. The guide told the story about how some early travellers decided to make use of the nice hot thermal pools to make their laundry washing easier. Needless to say they got quite a surprise when the geyser suddenly erupted, sending their soapy clothes everywhere!
The height of the geyser eruption depends on a few factors, including the pressure, temperature, and amount of water underground. In drought conditions the geyser is apparently slightly pathetic, but we were fortunate enough to see a good show. The geyser reached heights of about 10 meters and lasted for at least half an hour when we were there.
After visiting the geyser we drove back to the Wai-o-tapu visitor centre, parked, checked out the extensive gift shop just for fun, and then went for a walk. There are three different options of walking paths, ranging from 1.5 kilometers to 3 kilometers total. The shortest walk requires no stairs and is a fairly gentle grade, appropriate for families with young children and strollers. It could probably also be used for wheelchairs.
Beneath the ground of Wai-o-tapu is a system of streams which are heated by magma from earlier eruptions. With the high pressures, the water reaches temperatures of over 300C, allowing it to absorb the minerals out of the rocks and transport them to the surface as steam. While it certainly doesn’t have a pleasant smell, it is interesting to see the large range of colours that are created. These are some of the colours that we saw and their associated minerals.
|Black||Sulphur and Carbon|
The first thing we saw was the ‘Devil’s Home’, which is the first example in the park of a collapsed crater. They are created when the acid underground causes the ground to collapse. The crater had very rough sides and a yellowish colour from the sulphur that had condensed along the sides.
The entire area of Wai-o-tapu was somewhat surreal, with the strange colours, steaming, and bubbling everywhere. I think one of the most impressive points to me was reaching the Terrace on the boardwalk. The Primrose Terrace sits directly beside the Champagne Pools, which were one of the main reasons that I wanted to visit Wai-O-Tapu. The Primrose Terrace are sinter terraces that are the largest in New Zealand. The water from the Champagne pool contains dissolved silica that is deposited as it flows down the terraces.
The Champagne Pool is quite impressive. 65 meters in diameter and 62 meters deep with temperatures around 74C, it is the largest in the area. It is difficult to see most of it due to the steam constantly rising from the surface, but the edges are always visible in their brilliant red hue.
We opted for the longer walk through Wai-o-tapu, which was mainly a pretty walk. I think all of the best sites are on the short walk, but it was a beautiful day so we didn’t regret it. The smell decreases on the longer walk, which gave our noses a bit of a welcome break. I enjoyed seeing the sulphur cave, which is almost entirely yellow and has sulphur crystals growing all around it. It was such a strange sight to see such vivid colours in a naturally occurring formation. I also enjoyed walking across ‘Frying Pan Flat’, which is an eruption crater littered with bubbling springs and steaming vents.
We finished up by listening to the Inferno Crater, which has violently boiling mud just out of sight. Peter Jackson recorded many sounds in the Inferno Crater that later became a part of Mordor. Right beside it is Bird’s Nest Crater, named for the Starlings, Swallows, and Mynahs that use the geothermal heat to incubate the eggs in their nests on the crater walls while the adults forage for food.
Our final stop was at the Devil’s Bath in Wai-o-tapu. It is a large pool that is a brilliant yellowish green colour. Think the stereotypical toxic waste sludge colour and you will be pretty close to the colour of this small lake. We asked one of the guides there about the colour and he said it was from the dissolved sulphur crystals in the water combined with light reflecting off of the minerals in the pool itself. Apparently if you took a glass out of the lake, it would appear nearly clear. Considering that the water is highly acidic (with a pH of around 2, for you science folks), you definitely wouldn’t want to drink the water here! Or even touch it really.
We finished off our day with a nice picnic lunch. We considered eating at the cafe that is on-site, but there were nice picnic tables right near the parking lot and we already had food in our campervan. On the way out we stopped at the bubbling mud pools, which are free to visit and are quite active. Well worth the stop!
Although Wai-o-tapu is a little bit expensive considering that you can see many of the same sights around Rotorua for free, we found it worthwhile to visit. I was glad that we had a discount voucher from our holiday park.