After a fourth pupil was reportedly hit by a vehicle outside a school this year, councillors say safety measures are required before "a serious accident happens".

The mayor of Watford and his Lib Dem colleagues are calling on Hertfordshire County Council to take action along Horseshoe Lane in Garston.

They have launched a petition urging the council to make the street safer for pedestrians.

Councillor Tim Williams said: "My child goes to one of the three schools along this road. All parents crossing in this area fear that a serious accident will occur at some time unless critical safety measures are completed."

The latest incident happened in the first week of September.

Cllr Karen Collett, who is also deputy mayor of Watford, said: "This is the fourth time this year there has been an accident involving a pupil from Francis Combe Academy. Something really must be done to prevent a life being lost.

"I know that Francis Combe have been contacting the county council on this for some time." Cllr Williams says a short-term move could be better signage, better traffic management, and better road safety awareness for children and parents, but long-term, he believes the council should go back to the drawing board because he believes there is space available to make road safety improvements.

Cllr Williams has been successful in getting a school crossing outside St. Catherine of Siena Catholic Primary School, but so far, the county has not been able to recruit someone to man the crossing.

Current safety measures in Horsehoe Lane include speed bumps and a chicane near Boundary Way.

Highways executive member at Hertfordshire County Council, Cllr Phil Bibby, says the council is aware of community concern regarding pedestrian safety in Horseshoe Lane but the street is not currently being treated as a "priority issue".

Cllr Bibby said: "Promoting and enabling active and sustainable travel is a priority. However we are limited by funding available in terms of delivering highway improvements.

"We do not currently have a highway improvement scheme in the programme for this location, and we can also confirm the site is not on the list of hazardous sites being investigated this year, as recorded accidents have not suggested a priority issue.

"Highways officers would be glad to discuss further with the local county councillor his ideas for improving the road, and if these could be put forward for consideration as a future scheme."

The Lib Dem road safety petition, which is being backed by Francis Combe Academy, can be viewed at http://www.watfordlibdems.org/safety_measures_for_horseshoe_lane