The pumps, part of flood protection infrastructure, were to replace four non-fish-friendly pumps that are past their use-by-date.
Project manager Stephen Wilson said the ship - with the pumps - was due to arrive in New Zealand the day before Christmas, but had been delayed by the lingering logistical impacts of Covid-19.
Wilson had been tracking the ship “anxiously”, when he heard it made it through the Suez Canal and across Red Sea mere days before pirates forced ship operators to re-route.
“There was a container ship that ... got hit by a rocket or [almost did], and then it happened again ... all the shipping companies diverted their routes after that, taking a lengthy detour of 3500 nautical miles, 6500 kilometres, around Cape of Good Hope,” Wilson said.
The new fish-friendly pumps in action in north Waikato. Photo / Waikato Regional Council
After their arrival in New Zealand, the pumps were able to be installed on time - and under budget - at Churchill East Pump Station near Te Kauwhata in April.
The pumps measure 18m in length and 3m in diameter, and can pump up to 2.25cu m per second.
Wilson said the old pumps, installed by the regional council in 1965, were past their use-by-date with one of them having failed.
Of the four pumps, one was almost constantly pumping water, with the second and third pump kicking in when required.
“Now, just one pump can keep on top of water levels by operating for an hour every six hours or so, on low speed.”
When the council considers replacing old flood protection infrastructure, it needs to comply with legislation, including fish passage requirements.
The design of the new pumps means tuna and eels can pass through unharmed, giving them access to the Waikato River to breed.
Wilson said the Archimedes screw pumps were part of a wider upgrade to the Churchill East Pump Station.
This upgrade included creating a coffer dam around the existing pump station and setting up backup pumps in case of wet weather.
Waikato Regional Council received $4.48 million from the Climate Resilience Covid-19 Response and Recovery Fund, for the fish-friendly upgrades of the pump stations and to scope out three other sites.
