In part one of this series, I used the case example of Khyber Pass Rd to show how we could be much smarter about bus priority than simple kerbside bus lanes, I also mentioned how taking the approach of quantity over quality has large opportunity costs beyond just effectiveness and cost.
In part two I showed how this can benefit town centres, in this post, I will show how being smart about bus priority leaves space for much-needed safe cycling infrastructure.
Great South Road between Newmarket and Ellerslie is an important bus corridor, but with the New Network now live in both the East and South the number of buses have significantly decreased. The major route left serving the corridor is the 70 that runs from Botany to Britomart. This bus runs every 10 minutes during the day, and peaks at around 10 buses per hour in the morning and evening peaks. Therefore peak volumes are lower than isthmus corridors like Dominion & Mount Eden Road. The bus also parallels the railway line so is used more for local trips. The corridor could also be great for cycling if upgraded as it would fill in a really big void in the current cycling network that exists between Newmarket and Otahuhu.
Unfortunately, as corridor space is scarce it is unlikely that the corridor could have both continuous kerbside bus lanes as well as protected cycle lanes, but if we think smartly about bus priority we should be able to solve the issue.
The issues for this corridor are congestion hotpots at Market Rd, Greenlane (especially the approach citybound approach), Main Highway intersections and some off-lane bus stops.
- The Main Highway issue can be mainly be fixed because the bus lane is in the wrong place. Buses city-bound only turn right onto Great South Road but the bus lane is kerbside even though there are no stops or parking on this section. By making the kerbside bus lane a median one buses won’t be stuck into the combined right/left stack but given priority onto the dedicated right turn stack. The phasing is also a little messy as well for this section with buses usually unable to pass through the lights without hitting one or two red lights, which surely could be fixed with an improved signal phasing.
- The offline stops are created de facto when bus lanes are not in operation and the lane reverts back to parking. This issue is fixed when the parking is largely removed and replaced with cycle infrastructure including best practice floating bus stops.
During the peak, the Greenlane section is bearable because a little priority has been put in place with kerbside bus lanes towards the intersection approach. Though the times for this lanes have to be even longer as this section is often busy due to the proximity to Greenlane motorway interchange which if anyone has used is inefficient and causes a mess.
It would be better if the current left turn stacking lane was made a peak bus priority pocket with its own advance B phase, this would allow the bus not only to not be affected by left turning traffic but the advance would give the bus time to merge back into the general Great South Road lane on the other side without undue hindrance.
One of the key elements to providing good priority for buses at intersections is to provide enough bus lane approach that it just exceeds where you expect the general traffic tailback to be.
The issue with Market Rd intersection is a little harder because of its nature as a small town centre. In the case, the solution is potentially similar to the Mt Eden Town Centre solution in post two with a B advance phase to give priority to buses through the town centre leaving the space spare for cycle infrastructure.
By focusing the bus priority at the key spots where it is necessary on this corridor, Great South Road won’t actually need full-length kerbside bus lanes on both sides of the street. Therefore, the midblock sections of the corridor will be able to have full length separated cycle lanes in each direction without having to shift kerbs which can be prohibitively expensive. Therefore the budget can be saved to allow full separated intersections to be built along the route. This will create a great north-south cycle route, which much better local access and at a lower cost than the southern motorway cycleway that has often been proposed to serve this corridor.
By being smart about bus priority we can provide both great outcomes for bus users while leaving space for fantastic safe cycle improvements win-win.