The preferred design for a walking and cycling route across Auckland's Harbour Bridge is a 5m-wide path flanking the southbound traffic side, linking Westhaven to Northcote Point and connecting with the future SeaPath route.

Photo: NZTA

The Transport Agency has this morning released plans for its preferred option for a shared path.

NZTA manager of system design and delivery Brett Gliddon said a 5m wide path would allow for separation between people on foot and on bikes, making it safer and more enjoyable for all users.

"We're confident this will deliver the safest, most enduring solution not only for people now but also for future generations, and that it will become much more than just a transport connection."

The agency said there would be no load restrictions because the path will be attached to the bridge piers rather than the clip on. That meant no restrictions on the number of people able to access the path at one time.

It said the path would have wide viewing galleries where people could gather without impeding the travel of pedestrians and cyclists, and could go ahead regardless of any future plans for an additional Waitemata Harbour connection.

The agency is continuing to work on SeaPath, a 4km shared path between Northcote Point and Esmonde Road, Takapuna to ensure the design coordinates with plans for the Harbour Bridge Shared Path.

Construction of the preferred option could start as early as next year, with funding already included in the National Land Transport Plan, the agency said.

Cycling advocacy group Bike Auckland welcomed the design and said construction couldn't come soon enough for the people of Auckland and the city's tourists.

"We're especially relieved to learn the Agency has committed to a design that captures the stunning essence of SkyPath, adds extra width, and works well with the existing structure," said chair Barb Cuthbert.

Photo: NZTA

In a statement, Ms Cuthbert urged the Transport Agency to give the public a clear idea of the timeline, and to identify and resolve any roadblocks. "Aucklanders are tired of delays, and deserve certainty."

Auckland Mayor Phil Goff has welcomed confirmation the construction of the walk and cycle path would start next year.

Photo: RNZ / Diego Opatowski

"Like most Aucklanders, I want to see this happen as soon as possible," Mr Goff said.

"Being able to walk and bike between the North Shore and the city centre for the first time will be exciting and transformative for the city.

Mr Gliddon said he couldn't give a timeframe when the path would be finished, but said by the end of 2022 would be a "fantastic outcome".

"We are committed to this and we're going to push it as hard as we can to deliver it as quickly as we can."

"We've looked at all sorts of options around how you could potentially do this. We've done the preliminary design, and the structural analysis to make sure it's workable - that's the stuff we've been doing over the last 12 months. Now we have to get into the detailed design of how we're going to build it," Mr Gliddon said.

All going well with the detailed design and consenting process, Mr Gliddon said they were aiming for construction to start at end of 2020, with around a two-year construction period.

An alternative design by the SkyPath Trust will not go ahead. It was a tube style and slightly underneath the bridge surface and already had resource consent which was supported by the Auckland Council.

Photo: NZTA

Mr Gliddon said the new design might need a separate resource consent, but given a consent deals with the effect the structure was likely to have, NZTA would try to utilise parts of the SkyPath's resource consent to expedite the process.

"If the effects aren't substantially different it may not need a full application, it may just need a variation. We just need to work through that and we'll engage with Auckland Council on that.

"We want to get this underway and built as soon as possible."

Mr Gliddon said it would cost more than $100 million dollars, which will be drawn from the National Land Transport Fund. He couldn't comment on the SkyPath Trust's projection that their design would cost $67 million - so this would be at least $30 million more - because he hadn't seen the Trust's detailed designs or how it got to that number.

It would also be wider than the SkyPath design, which was four metres across.

"We're saying five metres, it could even be wider. But the intent is to build five metres - that's best practice. When we build walking and cycling paths now anywhere around the city we aim for five metres. That provides enough room for cyclist and pedestrians to mix."

Mr Gliddon said the new design was safer in the case of an emergency, such as a fire, because it was level with the surface of the bridge, rather than being underneath. He also said it would be more stable.

"It's not connected to the clip-ons so it won't move up and down as much. The clip-ons move up to 700mm when heavy vehicles travel across it.

"There are a lot of benefits to the option we've got, so we're quite proud of it and think it's a really good, enduring option."

In a tweet, Associate Minister for Transport Julie Anne Genter welcomed the new design, saying people "deserve real choice when getting around our towns and cities".

"With e-bikes, commuting over the Auckland Harbour bridge should be a genuine alternative for many."