Environment Waikato has authorised the taking of ground water for pasture irrigation in Tauhei.
Landowners J and E Fransen applied to take up to 3024 cubic metres of water from an underground source for pasture irrigation near Valentine Rd. Twenty submissions were received from neighbours and the Tauhei School.
The water, from two bores, would be used to irrigate 67 hectares for a maximum of 80 days a year over summer. Mr Fransen had been farming in the area for 25 years and believed that lack of water had become a limiting factor for farming in the district.
Submitters were concerned about the pumping tests done by the applicant and the assumptions made about the ground water system in the area. Since the 1960s shallow bores had not been producing the required amounts of water and consequently many bores had been deepened, they said.
The proposal might cause an increased movement of water towards the deep aquifer, decreasing water quality in the shallow aquifer. This could mean further costs for shallow ground water users. One submitter said it was an inappropriate use of a limited resource.
Others were concerned about the potential for adverse effects on domestic and stock water supplies and the activity may cause land subsidence. Many in the area had experienced problems in getting sufficient ground water and bores had to be deepened. Submitters were concerned the proposal would exacerbate the problems.
Ten submitters had engaged a consultant to assess the potential effects of the proposal, who concluded that effects could not be clearly defined and there was considerable uncertainty about ground water resources in the Tauhei area.
Environment Waikato’s technical report said the application highlighted the increasing conflict between small, established ground water users versus large scale abstraction.
A worst case assessment indicated minor draw down effects on shallow users and the potential for significant draw down in neighbouring deep bores. The proposed take was significant, equating to 20 percent of the resource but was considered sustainable in terms of total recharge to the deep aquifer.
Future use of the deep aquifer may be restricted if the consent was granted. Effects on nearby users could be controlled by stringent monitoring conditions and a review condition.
Granting the consent, the Committee acknowledged that considerable cost may be incurred by the applicant to install a new deep observation bore for water level monitoring, but this measure was considered essential. The consent was granted for 10 years, and proposed monitoring conditions, including amendments arising from the hearing, provided adequate warning of the emergence of significant draw down effects in the deep aquifer.
The proposed cut off condition would provide sufficient protection for neighbouring users, it said.