Lake Rerewhakaaitu is a small, shallow

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

in northern

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

, located 30 kilometres to the east of

Rotorua Rotorua () is a city in the Bay of Plenty region of New Zealand's North Island. The city lies on the southern shores of Lake Rotorua, from which it takes its name. It is the seat of the Rotorua Lakes District, a territorial authority encompass ...

. It is immediately south of the active

volcano A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are ...

Mount Tarawera Mount Tarawera is a volcano on the North Island of New Zealand within the older but volcanically productive Ōkataina Caldera. Located 24 kilometres southeast of Rotorua, it consists of a series of rhyolitic lava domes that were fissured d ...

, and the geography was substantially altered by the

1886 eruption of Mount Tarawera In 1886, a violent eruption occurred at Mount Tarawera, near the city of Rotorua on New Zealand's North Island. At an estimated Volcanic Explosivity Index of 5, the eruption is the largest and deadliest in New Zealand during the past 500 years, w ...

Geography

At a mean autumn height of above sea level the lake is highest and southernmost of the Rotorua Te Arawa lakes. Occupying a shallow basin, it is mostly surrounded by farming pasture; although over the past few decades, exotic and indigenous forest cover has begun to appear.

Water Flow

The lake is feed by the Awaroa and Mangakino Streams. The lake has no permanent outflow, as it is above the water table of much of the surrounding land ( by perhaps up to except at north-eastern side), but has an artificial overflow channel to the south east to control the maximum height. Also, when the lake is high, water can flow down the Mangaharakeke Stream due to these water table issues. Further the Awaroa Stream is ephemeral. It is believed that the springs at the head of Te Kauae Stream are sourced from the lake as part of ground water outflow from its catchment into that of

Lake Rotomahana Lake Rotomahana is an lake in northern New Zealand, located 20 kilometres to the south-east of Rotorua. It is immediately south-west of the dormant volcano Mount Tarawera, and its geography was substantially altered by a major 1886 eruption of ...

to its north-west. Groundwater also flows south-east of the lake into the Rangitaiki River catchment.

Geology

The lake is believed to be about 11,000 years old, having formed after the Waiohau eruption of 14,009 ± 155 years ago. The area of the lake and its catchment has multiple

rhyolitic Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained groundmass. The mineral ...

pyroclastics Pyroclastic rocks (derived from the el, πῦρ, links=no, meaning fire; and , meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroc ...

from Mount Tarawera eruptions. Parts of the Whakamaru Group of ignimbrite define the south-east and parts of the northern lake shore, and that massive eruption sequence of the Whakamaru Caldera was about 335,000 years ago. The 1886 eruption of Mount Tarawera covered the lake area in

tephra Tephra is fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, they rem ...

to a depth between . Some of the ash deposits in the catchment, particularly the even thicker ones to the north of the lake, would have been washed into the lake within a year or two as described at the time.

Ecology

The lake is home to 46 different bird species with nine of these classified as threatened. This includes the largest breeding population of

banded dotterel The double-banded plover (''Charadrius bicinctus''), known as the banded dotterel or pohowera in New Zealand, is a species of bird in the plover family. Two subspecies are recognised: the nominate ''Charadrius bicinctus bicinctus'', which breeds ...

in the Rotorua Ecological District. It is stocked with introduced

Rainbow trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coasta ...

. The lake is classified as mesotrophic, with moderate productivity and water quality. Its

trophic level index The trophic level index (TLI) is used in New Zealand as a measure of nutrient status of lakes. It is similar to the trophic state index but was proposed as alternative that suited New Zealand. The system uses four criteria, phosphorus and nitrog ...

was 3.4 in 2014.

Culture

The shores of the lake are often the scene of dog shows, like those from Rotorua, Agility during Easter, and the obedience show in January.

Education

Lake Rerewhakaaitu School is a co-educational state primary school for Year 1 to 8 students, with a roll of as of .

References

{{Rotorua District Rotorua Lakes District Rerewhakaaitu, Lake Populated places in the Bay of Plenty Region