Second Harbour Crossing, Auckland

The alternative motorway route around the edge of the harbour is also near peak capacity despite widening programs, and is easily gridlocked if the bridge is closed due to an accident or adverse weather conditions.

In 1860, John Bell designed a drawbridge on floating pontoons that would have given cattle and pig farmers in the rural North Shore a more direct route for driving their livestock into the city.

[4] A Royal Commission in 1946 recommended a four-lane road bridge, but further modelling predicted that there would be a population boom in the North Shore after being connected to the CBD, necessitating at least six lanes for future-proofing.

The Auckland Harbour Authority was established in 1951 to lobby for funding, seek tenders from architects and construction firms, and further develop the plans, which had now settled on a compromise five-lane bridge with two additional walking and cycling lanes.

[7] However, the substantial cost of any new crossing, as well as the disruption to communities on both sides of the harbour during construction—the North Shore is now a densely-populated urban district, unlike when the original bridge was built—has repeatedly dissuaded governments from investing in any specific plan.

In 2017, Auckland Transport's projections indicated that the Northern Busway would reach maximum capacity in 2026, twenty years earlier than originally expected, and there would soon be overcrowding at Albany, Sunnynook and Akoranga stations.

[24] In mid-2008, the Waitematā Harbour Crossing study group—a private lobbying group representing local companies—released their recommended option, which would have connected from the existing Esmonde and Onewa motorway interchanges on the North Shore side to Auckland CBD, reaching land in the southwestern part of the Wynyard Quarter (though the links would have continued as tunnels for some further distance, likely going under Victoria Park).

The option, selected from several hundred considered alignments, involved four separate tunnels, two for motor vehicles and two for public transport, the demolition of Victoria Park Viaduct, and a new rail station in the Wynyard Quarter.

[25] In mid-2009, Waka Kotahi NZ Transport Agency (NZTA)—the successor to Transit New Zealand—safeguarded the route so that further redevelopment on the Wynyard Quarter would not negatively affect the future tunnel.

The designers argued that the new bridge would pay for itself by freeing up 35 hectares of land (and 3.3 km of shoreline) for redevelopment in some of the most sought-after Auckland locations, like Saint Mary's Bay, which were currently taken up by large motorway approaches.

[30] However, critics argued that the extra investment required to meet the tight 2015 deadline would necessitate taking funds away from other crucial transport initiatives in the region.

[31] The then-mayor of North Shore, Andrew Williams, and the then-chairman of the Auckland Regional Council, Mike Lee, both supported the earlier studies into a tunnel.

[37] To save waiting for an entirely new crossing, in 2011 NZTA proposed focusing on only part of the 2010 recommendations and adding new pedestrian and cycling paths onto the existing bridge.

The plan initially had strong local support and was added to Auckland Transport's strategic priority list soon after, with resource consent sought and granted in 2016.

In 2019, NZTA commissioned consultancy firm PwC to examine the business cases for and against a wide range of second crossing options, taking into account historical proposals and current economic and demographic trends.

[13]In March 2023 Transport Minister Michael Wood announced a public consultation on five options for new "Waitematā Harbour Connections", informed by the findings of the 2019 review.

[52][53] National party leader Christopher Luxon expressed some support but with reservations over the proposed schedule and budget, describing it as "one of those projects we want to progress as well.

"[54] National's transport spokesperson Simeon Brown—a longtime critic of Auckland Light Rail—criticised both the projected cost and the inclusion of a rail tunnel in the plans, but also expressed general support otherwise.

Local planners also noted that without further funding from central government their only options for further transit investment in Auckland were new cycle lanes or continued upgrades to the Northern Busway.

Waka Kotahi NZTA chief executive Nicole Rosie criticised the entire Waitematā Harbour Connections planning and consultation process, telling the New Zealand Herald that, "we're making the same decisions they would have made seven to ten years ago—all that's happened in the meantime is the population has grown, the issue has become more urgent, and the costs have gone up.