Cranford clearway proposal is a highway by stealth

Currently, Christchurch City Council is working to solve the downstream effects of the Christchurch Northern Corridor (CNC) on Cranford Street. Predictably, abruptly ending a motorway in a residential area has made traffic almost unbearably bad there. The options on the table are to keep the current temporary bus lane, or switch to either a clearway or a T2 lane. So to make sure we weren’t repeating the mistakes of the past, we took a look at a previous clearway project in Ōtautahi and got a striking sense of déjà vu, as well as a premonition of the future.

A clear way forward for Curletts Road?

In 2013 NZ Transport Agency Waka Kotahi (NZTA) began consulting on a solution to a growing problem on Curletts Road in Upper Riccarton. Curletts Road is part of State Highway 73, and the section between Blenheim Road and Main South Road had seen an increase in traffic volumes after the earthquakes. At the time, this was attributed to traffic pattern changes caused by post-earthquake road works. Today it is largely due to the traffic pressure from the Christchurch Southern Motorway. This is similar to the increased traffic pressure currently being experienced on Cranford Street.

At the time, NZTA’s solution was introducing more traffic lanes. But there was a problem: much like Cranford Street, there was no room for an additional lane due to the on-street car parking. It may have technically been designated part of SH73, but in reality it was a residential road in a thriving local community, with residents able to park on the street. The local dairy relied on the availability of on-street parking. This resulted in a compromise, in the form of clearways.

Clearways are additional lanes for general car traffic, that operate only during peak hours (7am-9am and 4pm-6pm on weekdays). Outside these hours, the additional lanes (theoretically) revert to car parking.

That clearway on Curletts Road came into effect in May 2015. So what is the current state of Curletts Road?

Curletts clearway clearly failed.

Firstly, anyone who has driven on Curletts Road in the last few months may have noticed that the clearway signs have mysteriously disappeared, and for all intents and purposes it is now just two lanes of car traffic in each direction, 24/7. Where has the signage gone?

According to Downer SouthernLink, large trucks were hitting the signs, so earlier this year NZTA made the decision to take them down completely with no plans to replace them. We asked NZTA about this, and they contradicted SouthernLink, saying the signs were still there (they weren't), and would be put back up if they'd gone missing, and the clearway bylaw was still in force. There seems to be a lot of confusion about clearways, even among those tasked with administering them. Yet regardless of whether the clearway still exists on paper, it has unarguably been replaced by a de facto four-lane highway.

When we recently visited the road, we concluded that even if you are technically still allowed, you would be mad to park your car on Curletts Road, at any time. The sheer volume of traffic in all lanes on Curletts Road has made it unsuitable for on-street parking, even off-peak. We expect anyone attempting to park their car there now would suffer honking, abuse, or even damage to their vehicle. Plus, given the confusion from the administering agencies, we suspect parked cars could be ticketed or towed, despite technically still being allowed to park there. It is no wonder, then, that there are never cars parked on Curletts Road. There was no engagement, no opportunity for a vote. A four-lane highway has popped up in a residential area by stealth. We call this "highway creep".

Curletts Road is now a hostile place for everyone, whether you are on foot, on a bike, or even in a car. Any feeling of a safe and well-connected local community that may have existed before the clearway has been extinguished.

More lanes for cars means more cars.

Where has all this traffic come from? When we visited on a Saturday morning—well outside clearway hours—the traffic on Curletts Road filled both lanes. This is an example of what traffic engineers and economists call “induced demand”: if you increase the capacity for cars to drive down a road, the number of cars increases to meet the capacity. Congestion gets worse, and you find yourself back at square one. This is why Curletts Road can be congested even on a Saturday morning, with traffic crawling along both lanes.

We asked council staff whether they had taken into account induced demand when coming up with the three proposed options for Cranford Street. They answered:

Induced demand was not assessed in the Cranford Street project because the schemes are not significant enough to create any measurable induced demand effect.

Yet on page 31 of the Stantech Options Assessment Report, commissioned by council staff, the traffic design experts say:

One likely consequence of the clearway option will be higher traffic volumes on Cranford Street because the reduced travel times will make this route more attractive than alternative routes via side roads.

In other words, the clearway option will induce demand on Cranford Street. Did council staff even read their own report? More lanes mean more cars, and more cars means more congestion. Adding another lane for car traffic is an own-goal that will not improve the situation for commuters long-term. This means a clearway will not work to manage the downstream effects of the CNC, as required by the Environment Court ruling.

Unenforced rules may as well not exist.

Clearways also have an enforcement issue; which is to say, there is no enforcement. In the case of Curletts Road, there has never been enforcement, according to the CCC. Yet even if there had been enforcement, it seems the definition of "clearway enforcement" only extends to ticketing and towing parked cars during on-peak hours. In our engagement with the relevant agencies, it appears they hadn't even considered the possibility of ticketing drivers illegally driving in the clearway lane off-peak. Enforcement needs to go both ways with clearways: you need to remove parked cars during on-peak hours, and ticket drivers for using the clearway during off-peak hours, as a means of preventing highway creep. This one-directional thinking will turn Cranford Street into a highway.

T2 lanes share a lot of these negative qualities with clearways. The only T2 lane in Christchurch (north of Cranford on the CNC) is also currently not enforced in Christchurch, though NZTA have vaguely announced they plan to enforce this “soon”. This is eerily similar to promises of enforcement on Curletts Road back in 2015, which came to nothing. Currently, the T2 section of the CNC is a well-known joke among peak-hour commuters, with it mostly full of single-occupant car traffic. Plus, much like clearways, it has the effect of normalising that area of the road as a place for cars. It seems that if a lane is made available for car driving, even for a short time each day, then car drivers subconsciously feel entitled to use it, even when they technically shouldn’t. For these reasons, we believe the option of a T2 lane on Cranford St will eventually also experience “highway creep”, just like the clearway option will.

Where do we want Cranford Street to go?

Bus lanes don’t experience this “highway creep” like clearways do. Enforcement seems to be doing some good, but we think there is more to it than that. Peak-hour bus lanes all across Ōtautahi—including the current layout on Cranford Street—have continued to be used for on-street parking during off-peak hours (and sometimes during on-peak hours too, much to the annoyance of bus users). We suspect this is really because car drivers know bus lanes are for buses, and are never for cars to drive on. But if a lane is made available for car driving, even if technically for a short time each day, then car drivers subconsciously feel entitled to use it, even when they shouldn’t. Thus, it gradually becomes just another lane of car traffic.

So what does this mean for the future of Cranford Street? If we take Curletts Road as a recent example, we predict that the introduction of a clearway or a T2 lane on Cranford might briefly reduce travel times. Induced demand will then kick in, and in just a few years the volume of car traffic will increase until the road is just as congested as it has ever been, if not more so. Residents will be less and less comfortable parking on-street as their road swells in front of them. The neighbourly feeling of the community in the area will whither. Finally, Cranford St—just like Curletts Rd before it—will turn into a four-lane highway on a permanent basis.

Therefore, for elected members listening to the residents who don’t want a highway on their doorstep, keeping the peak-hour bus lane is the only choice.

The Waipapa-Innes-Central Community Board will be meeting to discuss their recommendation to council on November 14th 2024. The council will then consider their recommendation, and make a final decision at a later date. Follow us on Facebook and Twitter to keep up with our engagement on this and other topics.