The Highways Agency are carrying out tests to find out what type of motorway bridges are safest for horses.

The first part of a trial to measure how horses react to different types of bridges was carried out by the Highways Agency this week over the M4 in Wiltshire.

Jon Wallsgrove, principal architect for the Highways Agency, which is carrying out the test, says: “There are a lot of conflicting ideas about what kind of bridgesare good for horses. As far as I know, nobody in the world has ever conducted an experiment to see what is best for them.

“We are testing two places – one which is used by cars and the other where only pedestrian and horses can go. On each one we will vary the height and transparency of the sides and test whether horses go better in single file or in pairs.”

The tests are being supported by the British Horse Society which is providing the riders who will fill in questionnaires.

One of the riders who rode in this week’s trial was Penny Reid, the BHS’s county bridleways officer for Berkshire.

“I have been trying to encourage the Highways Agency for ages to carry out empirical tests for horses on roads,” she said.

“People who design roads rarely know anything about horses, but from today’s experience they are clearly willing to learn and are very helpful.”

Penny said her first impression from riding one of the more difficult horses across the bridge was that the more narrow the bridge, the higher the parapet should be.

The results of the trials will be used to update the Highway Agency’s standard on equestrian bridges throughout the country. The report is due to be published in April 2002.