Lake Rotomahana

Lake Rotomahana
Black swan on Lake Rotomahana
Location	North Island
Coordinates	38°16′S 176°27′E / 38.267°S 176.450°ECoordinates: 38°16′S 176°27′E / 38.267°S 176.450°E
Lake type	crater lake
Primary outflows	none
Basin countries	New Zealand
Max. length	6.2 km (3.9 mi)[1]
Max. width	2.8 km (1.7 mi)[1]
Surface area	8.0 km^2 (3.1 sq mi)[1]
Average depth	51 m (167 ft)[1]
Max. depth	112.4 m (369 ft)[1]
Surface elevation	337 m (1,106 ft)[2]
References	[1]

Lake Rotomahana is an 800-hectare (2,000-acre)^[1] lake in northern New Zealand, located 25 kilometres to the east of Rotorua. It is immediately southwest of the dormant volcano Mount Tarawera, and its geography was substantially altered by a major 1886 eruption of Mount Tarawera. Along with the mountain, it lies within the Okataina caldera.

Before the 1886 eruption, only two small lakes were present in the current lake's basin. Following the eruption, a number of craters filled over the course of 15 years to form today's Lake Rotomahana. It is the most recently formed larger natural lake in New Zealand, and the deepest in the Rotorua district. The lake's northern shore lies close to the 39 metres (128 ft) lower Lake Tarawera, separated by less than 700 metres (2,300 ft) of terrain that is mostly material from the 1886 eruption. Lake Rotomahana has no natural outlet, and its water level varies by about one meter in response to rainfall and evaporation.^[3]

The lake is a wildlife refuge, with all hunting of birds prohibited. A healthy population of black swan inhabits the lake, and there are efforts underway to ensure the lake's largest island, Patiti Island, is kept pest-free.^[4]

A boat cruise on the lake, visiting hydrothermal features on the lake's shore, is available as an additional extra from the Waimangu Volcanic Valley tourism operation.

Steaming cliffs on the shore of Lake Rotomahana

Pink and White Terraces

The Pink and White Terraces were a natural wonder on the shores of the lake before the 1886 eruption. They were considered to be the eighth wonder of the natural world and were New Zealand's most famous tourist attraction during the mid 19th century, but were buried or destroyed by the eruption.

Scientists rediscovered the lower tiers of the Pink and White Terraces on the lake bed at a depth of 60 metres (200 ft) in 2011.^[5]

References

1. Lowe, D.J., Green, J.D. (1987). Viner, A.B., ed. Inland waters of New Zealand. Wellington: DSIR Science Information Publishing Centre. pp. 471–474. ISBN 0-477-06799-9.
2. LINZ Topo50 Map BF37
3. Information panel at Lake Rotomahana's shore
4. "Patiti Island Environmental Restoration". Waimangu Volcanic Valley. Retrieved 2014-12-30.
5. Wylie, Robin (28 April 2016). "A natural wonder lost to a volcano has been rediscovered". earth. BBC.

External links

• Pink & White Terraces photos
• The 1886 eruption
• The Pink and White terraces 2011