States reveals traffic study data and defends timing

Friday 30 July 2021

A major data collection exercise of arterial routes into and across St Peter Port provides a "comprehensive picture" of Town traffic, according to the States, which has downplayed the impact of reduced school traffic at the time of the summer study.

The study used automated counters for seven days from Wednesday 7 July, to record the volume and frequency of traffic on main roads around central St Peter Port.

In total, 917,716 vehicle movements were recorded during the week. A separate camera survey was conducted over 24 hours, focussing on traffic going through junctions and roundabouts.

Of the 15 ATC locations, the heaviest traffic was along Glategny Esplanade. That recorded nearly 138,000 journeys, travelling at an average speed of 23.3mph. The next busiest road was St Julian’s Avenue, with 118,265 vehicles over seven days and an average speed of 20.8mph. 

These two roads shared the busiest junction, with nearly 30,844 traffic movements recorded at the Weighbridge Roundabout in 24 hours. 

Pictured: Elizabeth College was one of the schools closed at the time the survey was carried out. 

Express posed additional questions to the States before the study took place at the beginning of this month. These related to the merits of conducting the survey during summer school closures and whether the results would be representative of normal traffic volumes. 

Elizabeth College, Ladies College and other St Peter Port-based private junior schools had already broken up for the summer holidays. Le Val des Terres, was also closed for the first three days of the survey. 

The States did not respond to those questions at the time. Wrapping up their reply into a post-survey media release instead, a spokesman said that studies of this nature rarely take place in an entirely ‘normal’ situation. 

“Traffic flows vary throughout the year and are affected by many different factors, not least of roadworks, which can have some impact on some routes in and out of Town," they said. 

Pictured: Le Val des Terres reopened midway through the seven-day study, meaning that data was collected under both conditions.

"You need to be aware of the circumstances at the time to understand any limitations in the data and account for those wherever necessary. The companies who carry out these studies are very experienced in that, and have the expertise in analysing and interpreting the results, and can make adjustments if required.” 

The spokesman said that a smaller-scale survey can be carried out to supplement this work during the full school term.

“We expect that with two schools being shut there will have been some reduction in vehicle movements for an hour in the morning and again in the afternoon. Outside of those times, traffic should broadly be the same as during term time, all other things being equal. 

“To gauge the additional term time traffic would not require the whole exercise to be repeated. We can simply collect some more localised data when the colleges are back, to supplement the information already gathered.” 

They reiterated that the survey provides "a comprehensive picture" of current traffic volumes and flows throughout the day and across a full week. "This can be used as a baseline in future to predict what impacts may arise from certain types of developments in any particular location."