The Rotorua Geothermal System underlies part of Rotorua City, from the southwestern end of Lake Rotorua to the Whakarewarewa Valley (see map below). It is part of the Taupō Volcanic Zone, which extends from Whakaari-White Island in the Bay of Plenty, southwest to Mt Ruapehu. Fluid within the system can be in excess of 230°C, with high levels of existing use and many surface features.
The hundreds of surface features in Rotorua have important economic, ecological, landscape and cultural values. They are considered national treasures and part of our heritage. Rotorua's array of geothermal features, including volcanic crater lakes, spouting geysers, bubbling mud pools, hissing fumaroles and colourful sinter terraces, have been attracting visitors to the city since the mid-1800s.
They remain a major tourist attraction today and are the most popular sight-seeing destination for international visitors.
Whakarewarewa cooking by a hot pool in Rotorua.
Ohinemutu washing day by a hot pool in Rotorua.
The Rotorua system is unique in a number of ways. It contains one of New Zealand’s last remaining areas of major geyser activity. It is also internationally recognised for scientific research and has provided the basis for the evolution of many geothermal models and geological theories.
There are several other geothermal areas close to the city, such as Tikitere and Waimangu, but these systems have different characteristics and are managed separately.
Rotorua’s geothermal surface features are one of the greatest draw-cards for international tourists, with nearly half of all visitors coming specifically to see and experience the district’s geothermal wonders.
Over time it has become clear that the Rotorua geothermal system cannot meet unlimited demand for heat energy, with previous excessive use of fluid having adverse effects, particularly on the geothermal surface features and the long-term energy potential of the reservoir. Ongoing careful allocation of the resource is important.
Rotorua geothermal system (video)
The Ngā Whakaaetanga-ā-Ture ki Te Taiao ā Toi (Statutory Acknowledgements in the Bay of Plenty) is a compendium document to be read as an attachment to and in conjunction with the Operative Rotorua Geothermal Regional Plan including proposed regional plan or policy statement, and any variation or change notified by the Bay of Plenty Regional Council.
Rotorua’s geothermal surface features have been used in a low impact way by Māori for hundreds of years, for practical as well as spiritual purposes.
Extractive use of the system began in the 1870s when Rotorua became a tourist destination, influencing settlement patterns. Demand for commercial and residential use increased further in the 1930s and following energy shortages in the early 1950s extraction of geothermal heat and fluid for private use became commonplace.
By the 1970s more than 1,000 bores had been drilled with depths of 50 to 200 metres below the surface. As a result many geothermal features and activity in Whakarewarewa Valley, Kuirau Park and Arikikapakapa began to decline significantly. In the mid-late 1980s Government stepped in, forcing the compulsory closure of many wells, including all wells within 1.5 kilometres of the Pohutu Geyser, and imposing consent requirements.
Subsequently, geothermal features have recovered and the system has stabilised, with fewer natural events such as hydrothermal eruptions.
Some of the significant geothermal features within and around Rotorua urban area – most notably in Kuirau Park – are the same today as they were in the 1920s. While much of this recovery was rapid, some has taken longer. For example, the Papakura Geyser in Whakarewarewa valley began erupting in September 2015 after being dormant for over 30 years.
Geothermal resources have been an integral part of Māori culture for hundreds of years, with the Bay of Plenty’s Te Arawa people regarding them as a taonga (treasure). Te Arawa have for generations regarded the geothermal resource as a gift from the Atua, and call it waiariki, water of the gods. For Te Arawa, waiariki gives them physical and spiritual comfort; it is interwoven into their culture and traditions and is a major component of their tribal identity. Te Arawa kaitiaki require that any activity that would adversely affect the mauri of their waiariki must be avoided or controlled.
Māori have traditionally used heated waters for cooking, washing, bathing, heating, preserving, ceremonial use and healing. Rotorua was also the birthplace of tourism in New Zealand, with visitors travelling from throughout the world since the 1800s to experience the region’s geothermal wonders and Māori hospitality.
The resource remains integral to Māori culture today, particularly in Rotorua, which has one of the largest and most active geothermal fields in the world. Examples of its rich heritage include the communities of Whakarewarewa Valley geothermal field – the most visited tourist attraction in New Zealand – and Ōhinemutu, and the more recent Victorian setting of Government Gardens, the Bathhouse (now the Rotorua Museum) and the Blue Baths.
The earliest legends speak of a man named Ngatoroirangi, a tohunga (priest) from Hawaiki who guided the Te Arawa waka (canoe) to New Zealand.
Anxious to explore, he travelled down the east coast from Maketū, until he reached the Tarawera River. There, he turned inland and travelled up the river to the peak of Mt Tarawera and on until he finally reached the magnificent mountains that now form the Tongariro National Park. As he neared the top of the highest peak, he was affected by an intense cold so severe, he feared he would die.
In desperation he prayed to his sisters in Hawaiki (said to be the ancestral home of all Māori before they came to New Zealand) to send fire to warm him.
His sisters heard Ngatoroirangi’s prayer and called upon the fire demons to go to their brother’s aid. So Te Pupu and Te Hoata plunged into the sea and swam across the Pacific Ocean.
Each time the fire demons lifted their heads into the air from deep within the earth’s crust – first at Whakaari/White Island), then at Moutohorā (Whale) Island, Awakeri, Rotoehu, Rotoiti, Rotorua, Whakarewarewa, Tarawera, Orakeikorako, Taupō, and Turangi – they left a steaming, bubbling trail of thermal activity in their wake.
Like a flash of lightening the demons burst through the enormous cone of Tongariro, arriving as Ngatoroirangi lay near death.
The volcanic heat brought by the fire demons slowly revived Ngatoroirangi, spreading warmth through his veins and sending life to his muscle and bone. He named the mountain Tongariro to commemorate the cold south wind that almost killed him.
And so it is that volcanic and thermal activity came to the region.
Source: Edited from the book Te Whakarewarewa by Don Stafford.