SID Traffic Data

Shorne Parish Council operates a speed indicator device (SID), which is periodically moved between fixed locations at Pear Tree Lane, Tanyard Hill, and Thong, where it can face in either direction.

The SID is set to display information to oncoming traffic to help educate and inform drivers. It displays the speed of vehicles travelling between 27 mph and 30 mph. For vehicles travelling over 30 mph and up to 40 mph, it displays a “SLOW DOWN” message in addition to the vehicle speed. For vehicles travelling above 40 mph, it displays the “SLOW DOWN” message only. In addition, trained volunteers periodically carry out Police-approved Speedwatch sessions at the SID locations.

The SID records data regarding traffic volumes and vehicle speeds by the hour, day, week, etc, and we are able to analyse the data in detail. Over a period of 3 years, the SID has recorded data on 1 million vehicle movements.

Perhaps the most useful data recorded is the 85th percentile speed. This is the speed at or below which 85% of vehicles travel. The data clearly indicates that during this time, the SID (coupled with Speedwatch monitoring) has had a positive effect in reducing speeds. The 85th percentile speed at all locations has reduced, as has the percentage of vehicles exceeding the 35 mph “enforcement” threshold. This is the speed at or above which the Police may take enforcement action on an offender.

Unfortunately there will always be the odd vehicle recorded travelling at high speed, irrespective of the speed limit. The SID does not identify whether these are emergency vehicles or reckless drivers. Thankfully detailed analysis of the SID data shows that these are relatively isolated occurrences, and that the vast majority of vehicles travel within or close to the speed limits.

This is where we will periodically post brief summaries of the traffic data recorded. The attachments below are shown with the latest data at the top, oldest at the bottom.