A mobile speed camera is to operate on a stretch of road in Worcestershire where there have been more than 50 collisions in three years.
Two people died in one incident while another six crashes resulted in serious injuries on the A46 near Evesham.
Slight injury was suffered in 46 crashes in the three years.
West Mercia Safer Roads Partnership said in one week in September 2009 28% of vehicles went above the 60mph (97 km/h) speed limit.
The Safer Roads Partnership in West Mercia said the initiative on the Sedgeberrow bypass was due to "the collision history on this section of the A46 and a demonstrated speeding problem".
The partnership in the West Mercia area is made up of 13 partner agencies including Worcestershire County Council, the Highways Agency and police.