Concrete Solution for Far North Fish Farm
Concrete Solution for Far North Fish Farm
IF you need any evidence about the versatility of
concrete then the Kingfish Farm being built by Ebert Construction for Parengarenga Inc. in the
Far North is a perfect example.
Eberts are specialists in these types of construction projects. They have produced many
processing plants for a range of industries.
The Fish Farm is being built at Te Pua Point at remote Paua, which is located on the
Parengarenga Harbour, 25 kilometres south of Cape Reinga - or the top of New Zealand.
The actual site is at the end of a rough eight kilometre gravel road off State Highway One.
Due to the remoteness of the location Firth Concrete’s Tom Brien explains that they
installed a batching plant on-site for Ebert Construction to produce most of the 1400
cubic metres of concrete. Due to the location over 11,000 bags of Golden Bay Cement has
been used.
“All of the walls – and there are a lot of walls – have been poured insitu,” explained
Tom Brien. “The project includes 32 fish races or tanks inside a fully enclosed and airconditioned
(to 27 degrees Celsius) structure that is 160 metres long. Initially the fish
farm will be home to 150 tonnes of Kingfish growing to 600 tonnes over a three year
period. It is a state-of-the-art structure to cater for these fish which require a very
controlled environment.”
The important microbiology aspect of the project is being provided by Danish company
InterAqua.
“The whole plant was basically built and formed on site,” says Ebert Construction site
manager Hans Stoffel. “In two months the team poured over 1000 cubic metres of
concrete, which isn’t actually a lot, but if you look at the complexities of the different
pours, it is. In two days the team would pour three 20 metre long walls towards the
construction of the 32 tanks.”
As work progressed the team picked up the pace.
“A four man crew boxed and poured more than 30 linear metres a day on average,”
adds Hans Stoffel.
The 30mpa insitu concrete was chosen for the tank walls over precast due to the
location and the fact that all of the walls were water retaining structures. With precast
concrete panels all of the joins would have to be sealed. Instead the 20 metre walls were
poured all at once without any joins. Precast panels were supplied for other parts of the
project from Whangarei.
The weather was a big headache for Ebert Construction. “It was either
heavy rain, hot sun or strong wind, and all of these conditions are bad
for concrete,” says Stoffel. “It meant pouring at certain times of the
day. If it was hot the pour was in the afternoon to get the shade. If
it was raining the pour was delayed. If it was too windy conditions
resembled a sandstorm so the concrete had to be covered up to protect
it from impurities.
Ebert Construction were assisted in the
construction of the Parengarenga fish farm by
Kaitaia’s Stonecraft Construction and Graham
Barry Builders of Rotorua.
The Parengarenga fish farm was due for
completion in May/June.