The Waikato’s famous geothermal features are at risk from land use practices such as farming and forestry, last week’s Environment Waikato Environment Committee heard.
Geothermal scientist Katherine Luketina said the Waikato contained 80 percent of New Zealand’s high temperature geothermal systems and many smaller isolated geothermal springs. The Region had five of the country’s seven geothermal power stations.
More than 75 percent of the Region’s sinter depositing springs and geysers had been destroyed by three energy projects – development of Wairakei Power Station in 1958, building of Lake Taupo’s control gates and the creation of Lake Ohakuri in 1961.
Different uses the geothermal resource was put to were often incompatible with each other and with land uses in the surrounding area. In the past, the resource had been used for electricity generation with little or no consideration given to other uses such as leisure and biodiversity value.
Recent information showed that its use for tourism and leisure activities was very important, she said.
A survey of visitors found more than two million people visited geothermal attractions in the Waikato each year for bathing and nature tourism, which were important to the local economy. Sixty percent came from within New Zealand and 40 percent were from overseas.
Public bathing at geothermal attractions was the most popular activity with both groups. New Zealanders were most interested in the Wairakei borefield and the Prawn Park near Taupo. Overseas tourists preferred nature tourism, for which they were willing to pay.
She said information was being gathered to improve the management of the resource.
A stricter definition of a significant geothermal feature, based on rarity, resilience and viability was being developed, which would have important implications for future consents for use of the resource and for land use activities, such as vegetation clearance near geothermal features.
Geothermal bores and streams in the Wairakei-Tauhara and Ohaaki areas were monitored every six weeks for water level, temperature and flow rates, with records dating back to 1987. Other features were monitored quarterly for natural changes in behaviour and threats such as weed infiltration and logging operations. Staff then liased with landowners and users to reduce human effects.
Results had shown that geothermal features had remained fairly stable, although changes occurred from time to time due to weather and lake and river levels. Threats identified included forest harvesting, road works, tourism developments, stock access and diversion for non-commercial hot pools.
Chairman Lois Livingstone said the geothermal fields were an important part of the Taupo tourism industry.
“We have to recognise that geothermal resources have values other than for energy generation and it is vital to protect these remaining geothermal features.”