Heart of the City adviser Greg McKeown said most, if not all, of the freight movements would take place at night. Taking 350 nights, that is 2000 containers at night, or about 28 trains, he said.
Auckland Council has earmarked $700 million in the Auckland Plan for a third rail freight line between the port and Wiri.
The priority section of the track, says Auckland Transport, is between Westfield and Wiri, which has the greatest concentration of passenger and freight trains. Triple tracking between the port and Westfield is a lower priority and not likely to be required within the next 10 years.
Auckland Transport recognises that growth in rail freight eases pressure on the city's congested motorways and roads and is working with KiwiRail and Ports of Auckland on future rail options.
A spokesman for the council body says a final rail plan is not in place, but it is clear that current growth can be accommodated within the existing network and there are many options for how future rail freight growth can be accommodated over time.
With no final rail plan and limited details about the effect of port growth on motorways, particularly Grafton Gully, councillors are being asked to provide for more port expansion and harbour reclamation in the Unitary Plan.
The council had conducted the first stage of a review of development options at the port, but abandoned the stage two review looking at the wider impacts on the city.
The first stage of the review, an independent technical study by PricewaterhouseCoopers (PwC) of freight needs of the upper North Island ports, touched on Auckland's infrastructure coping with a growth in port freight.
Using a growth rate of about 2 per cent for the port, it projected the volume of road and rail traffic would increase between 73 per cent and 98 per cent by 2041. Ports of Auckland's growth figure is higher at about 3.8 per cent.
The review found the main potential roading bottleneck was at Grafton Gully where mostly non-port traffic would lead to a substantial increase in congestion. The same was true for the Southern Motorway, where port traffic accounts for about 2 per cent of traffic.
It was a different story with rail, with PwC predicting potential clashes between passenger and freight trains on the eastern and southern rail lines.
The study said there was likely to be sufficient capacity on the eastern line, but given the large increase in passenger services following the introduction of electric trains next year and 10-minute services at peak hours then freight train delays could result in considerable consequences for passenger services.
Additional freight trains running through the eastern suburbs - Orakei, Meadowbank and Panmure - would also have significant social effects and were already the subject of new design rules for new buildings around railway stations and tracks.
"Because of the intensive timetable, any disruptions to passenger services will have serious knock-on effects," the study found.
Ports of Auckland chief executive Tony Gibson refused to participate in the series on the port this week.
He said through a spokesman that debate over port expansion had been running for nearly two years and the company had contributed extensively to it.
But in a letter to Heart of the City chairman Terry Gould on April 24, Mr Gibson said the cost of upgrading Auckland rail for port business was well below the $700 million to $750 million figure quoted by the lobby group.
Mr Gibson said KiwiRail had estimated the line to the port could take passenger traffic and up to 1.17 million containers, less than what the port was likely to need. He said the line between Southdown and Wiri needed a third track - the section of track that Ports of Tauranga relied on to carry Auckland freight.
Mr Gibson said the $1 billion needed to upgrade Grafton Gully was not driven by the 7 per cent of port-related traffic, but non-port traffic.
Ports of Auckland communications head Matt Ball said the company supported the Grafton Gully improvements.
"As a general rule, we're supportive of infrastructure improvements that reduce congestion and improve the flow of freight. We have publicly stated our support for the central rail link," he said.
Mr Ball said port expansion would not affect the number of containers, which could grow to a figure of about 2.4 million on the currently consented Fergusson Wharf section of its waterfront business.
Expansion would affect the number of non-container movements, which are being consolidated at Bledisloe Wharf. It is this wharf that the ports company wants to expand up to 179m into the harbour.
A joint Transport Agency/Auckland Transport work group has been looking at the wider eastern waterfront area and found there was no need for a direct Grafton Gully to port connection, although progressive improvements were planned.
"At a strategic level, both the Transport Agency and Auckland Transport are working to get The Strand and Grafton Gully functioning more reliably ... this will allow port traffic to [be] moved progressively off Beach Rd on to the more efficient SH16 corridor, enabling Beach Rd to take on more of a city centre-type character and land uses," the Auckland Transport spokesman said.
Staged improvements would start with improved traffic signals and possible dedicated freight lanes and then fixing the bottlenecks at Stanley St/The Strand and The Strand/Quay St without tunnelling or a viaduct.
Planner and former Auckland regional councillor Dr Joel Cayford said the impact of expansion on existing infrastructure, its urban fabric and harbour edge urban environment had not been covered in the stage one technical study or by council officers.
"If it has, it has not been reported," he said.
Ports of Brisbane trade services general manager Peter Keyte said moving freight by rail was the best solution to create a liveable city, but the experience had been reduced freight moving in and out of the Port of Brisbane as passenger services increased.
Brisbane was exploring the opportunity for a new dedicated rail freight corridor.
Barry Copeland, chairman of the architects' Auckland Urban Issues group said a masterplan for port operations was needed with a broad scan towards a long-term future.
"This would factor in the need for the people to access the city waterfront, the availability of land, the many local and regional transport implications, and the amazing beauty and environmental importance of the Waitemata."
Aussie cities models of separating port and city
The cities of Sydney and Brisbane have moved their ports away from their centres.
Port Botany, located 12km south of Sydney's CBD, was commissioned in 1979 with its deep water channels and shorter sailing distance to open waters.
Brisbane, faced with the need to expand its port, moved its facilities in the late 1970s to the Fisherman Islands at the mouth of the Brisbane Harbour.
Alternatives to Auckland's inner-city port have been investigated and costed over the years, including an artificial island in the Firth of Thames and extensive dredging of Manukau Harbour.
A port in the Manukau Harbour has been considered in a Ports of Auckland study to be among the most expensive options because of extensive and continuous dredging required on its sandbar.
An option on the west coast, at Muriwai, was also assessed as difficult because of high waves.
An offshore port near Ponui Island would see island wharves built in the Firth of Thames, connected by road and rail bridges. Minimal dredging would be required, and it ranked in the middle of the pack for cost.
Capital costs for the alternative ports were estimated at about $3 billion, including transportation links.
The series
Monday: The plans for expansion
Yesterday: Ngati Whatua's opposition
Today: How port growth will affect Auckland.
What do you think?
Have your say on the port expansion plans.
Email newsdesk@nzherald.co.nz
