KEY PROJECT: The Otumahi Water Supply reservoir site 68 metres above sea level has been prepared for the construction of a reservoir that will hold 4200 cubic metres of water. Photo Whakatāne District Council
Diane McCarthy
TWO years on from purchasing land near Te Teko for a new water reservoir, Whakatāne District Council says it expects this key resilience project for the district to be finished early next year.
The reservoir will be able to hold 4200 cubic metres of water from the Otumahi Water Scheme on Paul Road, Te Teko, which serves Edgecumbe, Te Teko and surrounding areas.
The reservoir will provide increased resilience in the water supply in case of power outages to the bore pumps.
While the potential of piping aquifer water from the Otumahi supply into Whakatāne has been talked about at council meetings in the past as something that would be desirable for the town, no such plans are currently before council.
The Whakatāne and Ōhope supply is taken from the Whakatāne River.
Nearby resident Bruce Pearse has been watching progress of the operation closely as the hillside has been levelled ready for the reservoir to be built, mountains of earth stockpiled on the scheme’s bore site and a new bore drilled and pumps lowered, lifted and lowered again.
He felt little was known about the project by the public.
Three waters manager Glenn Cooper said most of the earthworks to support the reinforced concrete reservoir have been completed and the contract for building the reservoir awarded. All going to plan, the reservoir would be finished by March.
He said the reservoir site had proved to be very sound.
A preliminary geotechnical report had been prepared for the site three years ago and after a vehicle access track was built, more detailed fieldwork was carried out last year.
“During the excavation, no unexpected geotechnical issues have come up,” Mr Cooper said.
“The site was partly lowered eight months ago, and the rest of the excavation to complete the reservoir base has been under way for the past month. The base was initially planned to be set at 68 metres above sea level, but it was raised to 70.3 metres to increase the water pressure in the completed reservoir. This also reduced the amount of excavation needed.”
Material from the excavation had been temporarily stockpiled on the council- owned bore site on Paul Road.
Mr Cooper said that was because the regular vehicles used to transport earth were not able to reach the site and the material had to be moved by large off-road tractor trailers. The contractor had hired a subcontractor to take the material to an approved fill site.
Mr Cooper said it had recently received resource consent to operate a second bore at the Otumahi site.
The new bore is 160 metres deep with 40 metres of screening at the bottom. A submersible pump and pipes weighing, 5.5 tonnes had to be reinstalled after an initial test run revealed a fault in the screen casing connection, which allowed coarse pumice to enter the bore.
The pump and pipes were lifted out by crane, the connection fixed by the drilling company at no additional cost to the council, and the pump and pipes reinstalled.
Since 2022, the budget for the project, which includes a 2130m pipeline needed to connect the reservoir to the existing treatment plant and service area, has been revised from just over $5.15 million to over $5.48 million.
Mr Cooper said the updated quote reflected the increase in the pipe supply price.