The right way to reduce delays to Cambourne buses?

The Smart Cambridge data hub gathers real-time information about the position of every bus in Cambridgeshire. From this it’s been possible to track travel times along Madingley Road during the whole of 2019. This reveals something the Greater Cambridge Partnership (GCP) has never really acknowledged: that west of the M11 junction, there is no problem for outbound traffic. Fewer than 1% of journeys at all times of day experience delays of 2½ minutes or more, and most experience less than a minute’s delay.

The problem is only with traffic queuing down Madingley Hill to get into Cambridge, or onto the M11. Between around 8.30am and 9am on weekdays, buses experience delays of over 40 minutes about one day in four weeks. But it’s wildly inconsistent: they can also have delays of under a minute.

The solution, championed from the outset by the Local Liaison Forum, is to build an inbound bus lane. There are well-founded concerns about widening the road past the American Cemetery and a few other places. For this reason, Smarter Cambridge Transport has proposed an innovation, Inbound Flow Control, that requires less bus lane but still delivers significant benefit at relatively low cost.

The optimal package appears to comprise just over 1km of bus lane plus an extra eastbound lane between the Madingley Mulch roundabout and Madingley Wood. Combined with optimisations to signalling, junctions and filter lanes, that should save over 30 minutes on the slowest 5% of bus journeys, and slightly benefit other traffic too.

Drivers queuing for 45 minutes will see at least five buses overtake them. For anyone heading to west Cambridge or the Biomedical Campus, this will be a daily reminder that taking the bus could save them time – for some, more than a working week annually, even after allowing time to get to and from bus stops.

This is evidence-informed policy, something that is sorely lacking in GCP’s busways-everywhere strategy. An independent audit is underway of the Cambourne to Cambridge busway, which GCP has doggedly pursued since 2015 in the face of sustained opposition. Can we now hope for sense to prevail?

This article was first published in the Cambridge Independent on 27 January 2021.