Lake Rotorua 5.4

Lake Rotorua is the second largest lake in the North Island of New Zealand by surface area, and covers 79.8 km2. With a mean depth of only 10 metres it is considerably smaller than nearby Lake Tarawera in terms of volume of water. It is located in the Bay of Plenty region. The city of Rotorua is sited on its southern shore, and the town of Ngongotaha is at the western edge of the lake.The lake was formed from the crater of a large volcano in the Taupo Volcanic Zone. Its last major eruption was about 240,000 years ago. After the eruption, the magma chamber underneath the volcano collapsed. The circular depression left behind is the Rotorua Caldera, which is the site of the lake. Several other lakes of volcanic origin are located nearby to the east, around the base of the active volcano Mount Tarawera.Lake Rotorua is fed with water from a number of rivers and streams; some such as the Utuhina flow water of a water temperature warmer than the lake due to the thermal activity in the Rotorua area. Conversely streams on the northern shore such as the Hamurana Spring and the Awahou stream flow crystal clear water that has a constant temperature of 10 degrees Celsius. Other notable tributaries include the Ngongotaha stream, famous for trout fishing.