What's been happening
Walking through the Te Aroha Domain last November you may have noticed soil samples being taken in various spots, using a hand auger. An auger is like a manual drill and taking samples by hand meant there was little impact on the maunga (Mount Te Aroha) and vegetation. Before the initial geotechnical (or ground) investigations started iwi were involved in the planning and Ngāti Tumutumu led the karakia and cultural induction on the day the contractors began the work.
The soil samples tell us about the ground and this information will help with decisions about where a new day spa for Te Aroha could be located. The initial testing revealed that there is nothing fundamentally wrong with the geology to develop a new spa facility near the various sample locations (as shown below).
Once we have a better idea of what a new day spa facility will include and its extent, more invasive geotechnical investigations will be needed to confirm the area that is most suitable for development. How that will take place still needs to be worked through. Currently, the lower bush line is a preferred area for development - to take advantage of the spectacular views across the Waikato.
Geothermal water availability
Availability of geothermal water was the other critical risk being investigated, to determine what volume of geothermal water was available from the active geothermal bores in the Domain. The original feasibility study indicated that roughly double the amount of geothermal water would be needed for a larger facility. The investigation found that the existing Mokena bore should be able to supply enough water for a larger spa complex if we make use of the geothermal water that's currently going to waste.
Monitoring devices will be installed so we can collect data on where thermal heat is being lost. That will help us identify efficiency gains that can be made in future. Through another monitoring device we will also be able to determine how much fresh water is being used to cool the geothermal water.
Land stability and having enough geothermal water to support a larger day spa operation were two critical risks for the project. The findings from both investigations have given enough confidence to start developing a concept for the new day spa, including design options. This will be the main focus for 2022 and further expertise will be brought in to assist with this.