More than 5000 containers of imports, most of which would normally have been unloaded at Auckland's port, are stacked at the Port of Tauranga, which "desperately" needs more trains to rail them north, says chief executive Mark Cairns.
"We are absolutely chocker in the (container) terminal at the moment, trying to do our best to assist with the congestion problems at Ports of Auckland. As of today (April 7) we are operating at 101 per cent of terminal capacity with 19,727 TEU (containers) in the yard," Cairns said.
"We normally try to operate below 75 per cent yard utilisation for optimum productivity."
Cairns said 5355 TEUs of import containers that needed to go to the Tauranga port's south Auckland inland operation MetroPort were currently block stacked in the terminal "which is not ideal and most of these are containers that would normally be discharged in Auckland".
"It is very inefficient block stacking four containers high and then having to pick individual boxes that customers prioritise ... We desperately need additional trains to clear this backlog northbound."
The import clog can also be expensive for importers, which ultimately means Kiwi buyers of the imported goods, though in the case of the containers bound for MetroPort, the port is carrying the cost of their time at Tauranga.
Port of Tauranga normally charges $59.82 a day per TEU (20 foot equivalent) container for storage on the port after four days.
The port had returned to running a 78 train a week programme with KiwiRail last week but lost eight trains over Easter weekend due to track maintenance in Auckland.
The port worked with KiwiRail to maintain the track this way rather than having to close a line for two weeks over Christmas, Cairns said.
Discussions were continuing with KiwiRail about moving to an 86 to 90 train programme later this month, which would be "a gamechanger for us in handling additional imports for Auckland", he said.
KiwiRail is working "incredibly hard" with Port of Tauranga to provide more trains, said chief operating officer Todd Moyle.
"By the end of the month we aim to provide more capacity. But there's no silver bullet. A supply chain is that, a chain of different companies coming together for a solution."
Moyle said while a train could replace 90-100 trucks on a route, the logistics of bringing together locomotives, wagons and operating staff quickly was complicated, and there were also demands for service elsewhere. KiwiRail was working on increasing its train stock and operational staff.
Cairns said the port's current contracted train programme with state-owned KiwiRail this year was 62 trains a week.
"We aim for a normal delivery profile of 2-3 days average for everything and less than 36 hours for priority cargo. If we get the additional trains this will go a long way towards getting back to this normal delivery profile again."
It's also peak export season for Port of Tauranga, the country's largest port and its main export gateway, though the dairy export season is winding down.
As upper North Island supply chain congestion has worsened, the NZX-listed port company has introduced demurrage penalties to encourage exporters to respect its policy of containers having a maximum sitting time at the port of seven days ahead of their export vessel arriving. After that, the penalty clock starts ticking.
Ports of Auckland's free "dwell" time for containers is seven days, as is Lyttelton Port's.
"We would always prefer to receive no demurrage income and our exporters to minimise dwell (time) to ensure that we can maximise the throughput through our container terminal," said Cairns.
Fonterra, the country's biggest exporter, is one business willing to pay the penalty charge as the most cost-effective way to run its dairy export operations at the tail-end of its peak export period.
Gordon Carlyle, global supply chain director for Fonterra, said the tail-end of the peak meant the world's fifth largest dairy company by revenue, needed extra storage capacity for up to two months.
"We are always looking at the most cost-effective and efficient way to run our operations and, in this instance, continuing to store a limited number of containers at Port of Tauranga is the most efficient option for us."
Port of Tauranga, according to its website, after seven days dwell time, charges $38.07 a day for storage of a TEU and $76.14 a day for an FEU, 40 foot equivalent container.