Lake Rerewhakaaitu

Geography

At a mean autumn height of 434.9 m 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 fed 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 (perched by perhaps up to 5 m 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 442 L/s ground water outflow from its catchment into that of Lake Rotomahana 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 pyroclastics from Mount Tarawera eruptions.

The 1886 eruption of Mount Tarawera covered the lake area in tephra to a depth between 15 -. 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 in the Rotorua Ecological District.

It is stocked with introduced rainbow trout.

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

References

1. (1987). "Inland waters of New Zealand". DSIR Science Information Publishing Centre.
2. (2016). "Nitrogen discharge from the groundwater system to lakes and streams in the greater Lake Tarawera catchment GNS Science Consultancy Report 20151108".
3. "Lake Rerewhakaaitu Recreation Reserve: Nature and Conservation".
4. (2023). "Pre-conference tephra data workshop – Hands-on session II: tephra excursion, Okareka Loop Road (29 January 2023)". University of Waikato.
5. "Devastation caused by the Tarawera eruption". Te Ara - the Encyclopedia of New Zealand.
6. (1888). "Report on the Eruption of Tarawera and Rotomahana, N.Z.". Government Printer.
7. "Lake Rerewhaikaaitu". NZFishing.com.
8. "Lake Rerewhakaaitu". Land, Air, Water Aotearoa (LAWA).
9. "Dogs on best behaviour". Rotorua Daily Post.
10. "Ministry of Education School Profile". [[Ministry of Education (New Zealand).
11. "Education Review Office Report". [[Education Review Office]].