LTN OPPONENTS could be forgiven for renaming low traffic neighbourhoods “low traffic counters” as Loving Dalston reports on misleading vehicle counts.

LTNs have been hailed successful by London councils but it emerges that between 5% and 35% of cars, vans and lorries in slow-moving or stop-start traffic are not being counted. 

This pours doubts on the schemes, so mired in controversy they have set friend against friend and caused long-running arguments on Nextdoor and other chatrooms.

In a report on Hackney LTNs, John Wilde, of consulting engineers Charles and Associates, said: “Automatic traffic count surveys cannot be considered as broadly accurate [on congested roads]. A CCTV method survey would be more robust, and would also capture the stationary or slow-moving traffic conditions, while also allowing for clearer assessment of the peak periods.”

The Times has learnt that MetroCount, which makes the automated roadside counters used by most councils, advises against installing the counters’ rubber tubes on heavily congested roads because they under-record. They were “not designed to work” in stop-start traffic and should instead be deployed in “free-flowing conditions”.

As MetroCount explained, vehicles travelling very slowly might not be classified correctly, because “either the axle hits are too far apart so it splits them and places them into an unknown-vehicle class, which doesn’t get included by default, or it attaches those axle hits to a vehicle in front or behind”.

So if there is little or no congestion at the measuring points before an LTN, the number of vehicles counted is likely to be accurate. If, however, the LTN creates congestion at count locations, the post-implementation surveys will not report the true number of vehicles.

After Enfield council discovered a recording error, it reran all the data and added some under-counted vehicles. This changed a reported 5.7% traffic increase on boundary roads to 8% — a rise of more than a quarter. And critics claim that inherent limitations meant that in heavy congestion the new data still did not record vehicles.

Hackney council told Loving Dalston: “We use a variety of methods of industry-accepted traffic-counting, including live traffic cameras, manual visual counts by officers and the type of counters used by MetroCount.

“This means we don’t rely on any single technology and can cross reference results from each to minimise error, which is inherent in any kind of scientific equipment.”

Long-term Dalston resident Clair Battaglino, of Social and Environmental Justice, said: “Your report validates what many of us have been saying — small decreases in traffic on roads inside LTNs have caused significant increases on sacrificial residential roads, many of which have schools and nurseries in them and are actually the roads people walk along.” 

Hackney, she added, had been gaslighting victims like her while putting out misleading traffic counts.

David Altheer 170323

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* Backstory: Councillors benefit from LTNs; Hackney lets e-cars through LTN gates; Idle that engine — and risk an £80 fine; Hackney quietly ends limo perk

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