Google maps has a useful little tool, where you can not only see current traffic congestion levels, but also what conditions are ‘usually’ like at any particular time of day (show the traffic overlay and then change the box at the bottom to ‘typical traffic’. This makes it possible to take a look at where congestion is worst across the region at different times of day.
Starting first with Tuesday at 8am, which I’ve taken as a pretty good proxy for probably the heaviest ‘morning peak’. The first map shows the northern and western parts of Auckland:
Most main roads across the region are orange, which means that they’re busy but not totally congested. What you’d expect and hope to see. Main areas of congestion seem to be:
- Citybound on the Northern Motorway between Oteha Valley Road and Esmonde Road. It’s very notable that congestion eases significantly over the Harbour Bridge itself. Access onto the Northern Motorway at places like Esmonde Road and Onewa also seem to be highly congested.
- Westbound on State Highway 18 through Greenhithe. This seems to be largely caused by a lot of people driving from the west to the large number of jobs around Albany that are really poorly served by public transport.
- Citybound on the Northwest Motorway right from Westgate through to Western Springs. This is one of the main reasons why rapid transit to the Northwest is so essential.
- Citybound on the ‘inner’ Southern Motorway is pretty widespread, right through until Greenlane. Presumably this is caused by quite a lot of trips to the large employment area around Ellerslie and Penrose being pretty dependent on cars.
Looking next further to the south, you can see the citybound congestion on the Southern Motorway extends right down to Manukau City, and then again between Drury, Papakura and Takanini.
State Highway 20 is also quite congested between Manukau and Puhinui, presumably due to Western Ring Route traffic overlapping with people heading to the Airport along Puhinui Road. Ti Rakau Drive in East Auckland is also pretty congested.
Looking next at how things stand around midday, you can see how ‘peaked’ Auckland’s traffic is. The motorway network seems to work quite well during this ‘interpeak’ time:
There’s almost no red on this map, and most of the ‘orange’ seems to be in busy parts of the city where you’d expect traffic to go a bit slower, like the city centre, down Dominion Road and then around major centres like Manukau, Henderson, New Lynn and Onehunga.
Tracking forward to 5pm, as an indicator of the evening peak and there’s a lot more red on this map.
Some broad observations of the evening peak:
- Many of the main motorways are (somewhat unsurprisingly) a mirror image of the morning peak. Much of the northwest and northern motorways are jammed, although perhaps not quite as severely as in the morning.
- State highway 18 (Upper Harbour) seems to avoid pretty much any congestion in the evening, even though it gets pretty jammed up in the morning.
- Citybound congestion on the Northern Motorway is almost as bad as northbound congestion – which you would think is a bit surprising as this is counter-peak. Having only 3 lanes on the harbour bridge is obviously a key factor in this.
- There seems to be a lot more severe congestion in the city centre and through spaghetti junction in the evening peak than in the morning peak.
On this last point, I zoomed into the central area to take a closer look.
Some of the most severe congestion seems to be on the onramps to the major motorways, where traffic gets stuck at ramp signals. The fact that northbound lanes on State Highway 1 through spaghetti junction are green while the ramp signal is the very darkest red suggests that NZTA haven’t got the balance right – something I highlighted in this post a while back.
Looking to the south, it’s interesting that northbound (technically counterpeak) congestion is worse than southbound between Greenlane and Otahuhu. Further south the merging of State Highway 20 and State Highway 1 creates all sorts of issues around Manukau. There’s also quite a bottleneck where State Highway 20A from the Airport merges into the Western Ring Route.
So what can we make of these patterns? One thing that really stands out to me is that congestion seems worst (at least on the motorways where it appears to vary by time and place the most) for the kind of peak direction radial trip that public transport – especially rapid transit – is well suited to. Continuing to upgrade and expand rapid transit on the big corridors to the southeast, south, southwest, west, northwest and north is well suited to providing better travel choices for the very trips that face the most congestion.
For a little fun, I also made this gif showing how traffic levels every 20 minutes of the day from 6am to 10pm.
What stands out to you in these maps? Were you surprised by anything?