Traffic Speed Survey for Whiddon Down and Crockernwell Feb 2017


“Please provide data from traffic speed survey carried out at Crockernwell & Whiddon Down by highways between 4th and 12th February 2017”



Devon County Council (DCC) undertook traffic speed surveys in Crockernwell and Whiddon Down for one week in February 2017.

The Whiddon Down survey, which was undertaken on the A382 Exeter Road, between Chapel Hill and the roundabout, produced the following results:-

  • Mean speed = 35.1mph
  • 85th percentile speed = 41.2mph
  • Average 2-way traffic flow = 3,800 vehicles per day

Please note that ‘mean speed’ and ‘85th percentile speed’ (the speed at or below which 85% of vehicles are travelling) are the most commonly used measures of actual traffic speed

Unfortunately, the data for the Crockernwell survey became corrupted and is unusable. The data file is basically a series of numbers which are unintelligible unless viewed through the licensed commercial software.  Occasionally, the recording equipment produces corrupt data files where the numbers are clearly in error to the experienced eye, or so corrupt that the software cannot process it at all.

DCC has sent a copy of the corrupted file to our software supplier to see if they can resolve the issue.  If not, DCC may arrange a resurvey in due course, but unfortunately this information is currently not held in an intelligible way.


If you wish to speak with someone regarding the above request, please telephone 01392 383000 and ask for Information Governance or email