20mph probably won’t make Twickenham any safer, or any different.

In a data set the council released a few weeks ago, we now know that, in 2008, most traffic speeds through Twickenham, when not queuing, peaks at 42kph (~26mph) in two locations, but rarely makes it to the 32kph (20mph) line in many cases. (See the data here.Notes on the attachment: AADT – average daily traffic counts. LDV – light duty vehicle. HDV heavy duty vehicle. )

So the thing that the council and its officials have focussed on as a key safety measure is probably not going to make the blindest bit of difference to actual traffic speeds through the area. Potentially the changes in street furniture may cause drivers to slow down, but the removal of bus lanes and cycle lanes means there will likely be less potential conflict as vehicles move between lanes, and thus less reason to slow down.

The data also suggests that Cross Deep and London Road have around 20,000 vehicles per day moving through. This makes it an unpleasant enough environment for pedestrians and cyclists already, but in fact this data contradicts data from TfL’s Traffic Analysis Centre (5.7Mb PDF here.)

The TfL data shows that the King Street junction experiences in excess of 40,000 vehicles per day (scroll to page 11 and zoom in). How anyone thinks any part of Twickenham is going to create a cafe society with that many vehicles moving by is beyond me. And how anyone thinks you shouldn’t have dedicated facilities for cyclists in such a busy environment is beyond me as well.