Simon Wilson: Why we need a bike lane on the harbour bridge now


Q: What’s the best way to get a bike lane built?

A: Get them to build a motorway first.

True. Just look at the bike lanes and shared paths that run alongside the northwest motorway and down SH20 from Waterview to Mangere Bridge. When Waka Kotahi, the Transport Agency, builds a big road, they’re only too happy to put a bike lane next to it.

Maybe it’s because they believe in bike lanes. Maybe it’s just window dressing. Who cares? It gets done.

But not on the harbour bridge. Although we have learned SkyPath will not happen, for some reason, the same Waka Kotahi – and with it, the Government – cannot bear the idea of bikes using a lane on the bridge.

Let’s, ahem, park the arguments about cyclists for a moment. Let’s think about congestion.

In Seoul in 2003, they replaced the Cheonggyecheon expressway with a river and parkway. The traffic, strangely, disappeared. Seoul has now demolished 15 expressways, each time improving traffic flows and finding better things to do with the land.

Paris has recently taken two of the eight lanes out of its notoriously congested ring road, the Boulevard Peripherique, giving one of them to “public, emergency and zero-emissions vehicles” and planting trees in the other.

Traffic flows better now.

In London and Los Angeles, in Shanghai, Seattle and other cities all over the world … same.

A lot of people don’t want to believe this. But it’s not magical thinking.

Partly it’s because the roads have more capacity than people often think.

But something else is going on. More people use public transport, or walk or cycle. Many more just don’t do the commute. They work from home, or the local café, or new workplaces set up close to where they live.

The phenomenon has a name: “reduced demand”.

It’s the opposite of “induced demand”, which is what happens when you build more capacity into the roads. More people use them.

A lot of people don’t want to believe that either. But it’s not a new idea.

In 1962, a Chicago economist called Anthony Downs published a study called “The Law of Peak-Hour Expressway Congestion”.

“The real cause of peak-hour congestion is not poor planning,” he wrote, “but the operation of traffic equilibrium.” He called it Downs’ law, although he had the grace to add that it was, in effect, Parkinson’s law adapted to traffic.

Parkinson’s law, you may remember, is that work expands to fit the time available. Adapted to traffic, Downs said, it becomes: “On urban commuter expressways, peak-hour traffic congestion rises to meet maximum capacity.”

Aka the Field of Dreams law: if you build it, they will come.

If you offer commuters an empty road – extra motorway lanes, say – they will fill it up with cars.

Congestion gets worse. Carbon emissions go up. Angry drivers demand more roads. Throw in a misbegotten business case and repeat.

Downs’ law has been confirmed dozens of times over. In New Zealand, it wasn’t officially acknowledged until 2010, when the Transport Agency’s Economic Evaluation Manual declared: “[G]enerated traffic often fills a significant portion (50–90 per cent) of added urban roadway capacity.”

They know it. And yet, 11 years later, there is almost no evidence they accept that it’s true. Adding lanes to motorways remains, for all practical purposes, the core purpose of Waka Kotahi.

Fighting tooth and nail not to lose any of them is right up there too.

Goodness, imagine if they took a lane off the Auckland Harbour Bridge and the sky didn’t fall. What would be next?

That’s the background to a statement from Waka Kotahi this week that they can’t convert one of the lanes on the bridge for cycling.

“Our investigations have found that this isn’t a viable option,” said transport services general manager Brett Gliddon. “In practice it would require the removal of two traffic lanes, due to the need to provide a new traffic barrier to safely separate pedestrians and cyclists from traffic. This would significantly reduce the capacity of the bridge for all forms of cross-harbour traffic, including freight and public transport, creating a significant impact on Auckland’s transport system.

“There are also concerns that this option would provide a poor and potentially unsafe experience for pedestrians and cyclists, given … the narrow width of the shared path (likely less than 3 metres once barriers and screens are installed) and a challenging grade of 8 per cent.”

Deep breath. For the record, two lanes are not required. At their narrowest part, the clip-ons have a little over nine metres of roadway width, rail to rail. That would allow a two-way, 3m-wide cycleway, another metre for concrete barriers, and up to five metres for a traffic lane.

That’s better than what’s there now: 3.5m on the clip-ons and 3.1m in the central lanes. And the grade has always been described as 5 per cent. It’s a mystery how it’s gained another 3 per cent.

The bike lane couldn’t be shared with pedestrians, which is not ideal, but Waka Kotahi’s own research shows that most demand for a pathway on the bridge comes from commuters on bikes. That’s the priority demand.

And it might surprise non-bridge users to learn the bridge is not at capacity. Use is not growing, and although traffic gets clogged on the access ways at each end, it flows on the bridge itself. Existing traffic would cope fine.

Just as it does on Nelson St, Don McKinnon Drive, Tamaki Drive and everywhere else where vehicle lanes on busy roads have been converted to cycleways.

Cycling in Auckland is booming. Michael Tritt at the retailer Electrify says their sales have doubled in the last 12 months and it’s been a struggle to keep up with demand.

Tritt compares the Auckland bridge with Vancouver’s Burrard Bridge, where a lane was given over to cycling in 2009.

“Burrard Bridge bike lanes doomed to failure” and “Chaos feared”, said the headlines. Also, “Business plunging because of bike lane, owner says”. It sounds so familiar.

Ten years later, the Burrard carries a million bike trips a year and is the single busiest cycleway in North America.

Why is Waka Kotahi so opposed to a bike lane on the bridge? Because who knows where it would end?

Actually, they do know. Albany. A bike lane on the bridge requires urgency for the rest of the Northern Pathway, to connect the bridge to Akoranga and then to Constellation Drive.

The section from there to Albany is already underway. Of course it is: they’re widening the motorway. That is, still, how you get a cycleway built.

Meanwhile it seems there’s a proposal for a new bridge next to the current one, to carry rapid transit, bikes and pedestrians.

That’s fine, although also duplicitous: as late as December 17 Waka Kotahi told a transport safety group that its planning “does not include a walking and cycling connection across the bridge”.

Yet the Herald understands the proposal will soon be presented to Cabinet.

But hey. It’s a vastly cheaper option than a tunnel and should easily gain public approval. Good thinking, everyone involved.

That bridge, however, will be years away. Cyclists need a crossing now. And as explained above, the driver of every other vehicle on the bridge would be better off if they got one.

Come on Minister Michael Wood, here’s what you need to tell those recalcitrant officials: Take a lane! On yer bike!

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