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Tom Pike says, "there are no errors or missing data and there is no qualification of Steer's conclusions regarding the bus-time analysis of Route 94 along Action Lane and South Parade"This is what the report says, "It should be noted the Post-Streetspace data (September 2020) shows a sharp drop in vehicle flow on Thursday 17 September. This vehicle flow remains low during the rest of the survey period. These issues have been raised with the supplying survey company. They provided assurance that the drop (apart from the period early on the Thursday morning) is unlikely to be due to a tube defect as this was repaired. It is likely an unrecorded event caused this."I am not disputing the conclusion that the scheme had minimal impact on bus journey times during the four weeks in which they made the comparison.What I am saying is that this sample provides no sound basis for reaching a conclusion that the scheme has no impact on the 94.The period in which the comparison was made was when the access restriction signs had been put in place but there was little or no enforcement. The Steer report shows that during this period two thirds of drivers were ignoring the signs and continuing to drive through the underpass.Also the data shows that weekday traffic volumes on this road had fallen by 6% during the period under review compared with the pre-lockdown comparison period. Therefore it is unlikely bus travel times would have been affected negatively.However, borough wide traffic volumes had fallen by 23%. Therefore relatively traffic volumes in the vicinity of Fisher's Lane have risen significantly. Whether this is due to the access restriction is impossible to say for sure but the data should cause you concern.The conclusion of the Steer Report provides no basis whatsoever for concluding that there is no impact on bus journey times on an ongoing basis rather it covers only a short unrepresentative period.I know you don't like anecdotal evidence but we are hearing consistently from both users of the service and bus drivers that there has been a negative impact. In the absence of any credible data to contradict this, we should believe them.

Paul Corcoran ● 1988d

Firstly I am going to thank Tom Pike for directing my attention to the interim traffic analysis by Steer.IMO it was a very thoughtful report, where there were issues with the data (for example the age of some of the ATC data) the report clearly identified those issues and at least tried to correct for those issues.However, when it comes to bus times for the 94 bus I think there are some major lacuna in the analysis.  It is absolutely true as Tom has posted that the report showed that there was no appreciable difference in bus times along South Parade pre & post road closures. But there is a lack of analysis of the factors that might impact on bus times along that route.  In very simplistic terms the speed a bus can move along any stretch of road is determined by 3 things (1) volume of traffic which has obvious impacts on speed (2) how many stops a bus has to make on that road and (3) how long it stops at each stop which is probably a function of the number of passengers getting on or off.It is probably the case that the number of bus stops along the route did not change - I am going to assume that as it makes the analysis easy.What we know from the report is that across the borough traffic volumes declined by 25-26% but that for Acton Lane the traffic volumes declined by about 10% only due to covid.What we also know is that bus passenger capacity was significantly reduced because of Covid.  Not only that but that there was a significant move to working from home rather than in offices.  The combination of those 2 factors is likely to mean that number of passengers getting on or off the 94 bus at any particular stop would be reduced and that would result in the bus spending less time at the stop.  The problem is of course that we have no data as to how much of a difference this would have caused.The point is that the combination of less time held at bus stops and lower traffic volumes should have resulted in bus times reducing between the 2 periods looked at but as the report found, there has been no significant change in bus times.  IMO the most likely explanation is that the road closures have resulted in slower bus times but this is masked by the beneficial effects of lower traffic volumes and less time at bus stops

Justin Stephenson ● 1987d

Justin, I think you have correctly identified the contributions to the total bus travel times. However, there are some important considerations you have omitted that need to be taken into account, and these constrain how much difference changes in passenger loading times could have made. Looking at the data, there is rather less variation in the travel times compared to the other routes in the report. For the 94 the minimum travel time over this stretch is two minutes either way, and that's the same in both periods studied. The maximum travel time is rarely more than three minutes with a similar pattern in both periods analysed. In comparison the E3 travel time varies by more than a factor of three. Hence variability to both congestion and passenger numbers are relatively light on the 94 route, in both periods, adding at most 50% to the travel times.In fact as the 94 is right at one end of its route over the length studied, the number of passengers, and certainly the number getting off eastbound and on westbound, is rather limited. Hence the time at the stops to allow loading and unloading of passengers will always be a relatively low contribution to variability in the travel time, which itself is quite limited.Hence reduced passenger loading times could only make a very limited compensation to offset possible increased congestion, certainly no more than a small fraction of the variability in the period before COVID restrictions. In fact if you look in detail at the data the times became slightly shorter, probably from a combination of reduced traffic and lower passenger numbers. Certainly, there is no way that changes in passenger numbers could have masked gridlock!   

Tom Pike ● 1987d