Evaluation of the speed trailer as a community road safety resource in Christchurch
A speed trailer, a type of speed information device that tells vehicles how fast they are travelling, has been used in Christchurch for several years. The Christchurch City Council and the Land Transport Safety Authority evaluated the effectiveness of speed trailers using four separate surveys. Measurement of the speeds of free running vehicles before and after the speed trailer with a control survey when the trailer was not present found that the trailer had an effect on speeds for at least 200 metres downstream of the trailer. A survey of 27 schools found that most thought the trailer had an effect on vehicle speeds, raised awareness of vehicle speeds, and helped learning about speeds. Most would like to use the trailer again and were positive and supportive of the trailer. A survey of 544 drivers, interviewed after they had passed the trailer, found most had noticed it and knew what it was. The majority said it made them more aware of their speeds. Nearly half the drivers made positive comments about the trailer. People who regularly installed the trailer were surveyed. They had found no serious shortcomings but thought the trailer could be lighter and more damp proof. The researchers concluded that the trailer does slow traffic, it makes drivers more aware of their speeds and it provides an educational tool for schools and their communities.