Director general of health Dr Ashley Bloomfield said a building had been made available at the port where eight nurses, admin and IT support would be based "through the week for as long as they need to".
He said workers who may have had contact with crew on ships would be the priority for testing first.
The updates came after the Port of Tauranga issued a media release yesterdaystating the port and maritime community was being targeted for testing to rule it out as a virus source.
"Everyone who has been at the Port of Tauranga since 11.59pm, Tuesday, July 21, is now required by law to get a test for Covid-19," the release said.
Port of Tauranga chief executive Mark Cairns said the port was working with the Bay of Plenty District Health Board to provide testing facilities onsite.
The testing will include shipping agents, stevedores, drivers picking up or delivering cargo, contractors, suppliers of goods and services, classification societies, government agency employees and any crew members who may have come ashore.
But a port spokeswoman said: "Work groups are separated at the moment due to Covid-19 precautions so it would be highly unlikely that any infection would spread far."
Road Transport Forum chief executive Nick Leggett then issued a media release stating the testing order was "causing mayhem at ports for trucking operators".
"There doesn't seem to be the capacity to test them in this panicked timeframe."
"Drivers come into contact with hardly anyone at the ports," he said.
Later on Saturday, the Bay of Plenty DHB issued a media release with updated advice from the director general of health, Dr Ashley Bloomfield.
"Our border workers play an important role in doing their jobs and keeping us safe ... It is pragmatic to take a few more days to ensure we've tested as many of our port workers as possible."
The DHB's interim chief executive Simon Everitt said: "Port of Tauranga staff will be contacted by their company to allocate them a testing slot."
He said workers with any symptoms were getting tested by GPs offsite.
"If a staff member is unwell or has symptoms, please seek treatment from their GP and remain off work. In the meantime, we acknowledge the uncertainty that workers have been feeling about how to organise their tests."
The DHB's incident controller, Dr Joe Bourne said port staff could continue to work until before and after testing if they do not have symptoms or a positive result.
Covid-19 symptoms include a cough, a high temperature (at least 38C), shortness of breath, a sore throat, sneezing and runny nose and temporary loss of smell.