More than 900 drivers have been prosecuted for "appalling" driving offences in roadworks on the A13 in Essex since 1 November last year.
Police began the crackdown after drivers flouted laws during roadworks at Sadlers Farm roundabout at Benfleet.
Police motorcyclists were called in to help enforce a temporary 50mph speed limit introduced in November 2010.
Contractors and Essex County Council are funding the extra patrols to protect workers and cutting speeding.
"The speed restriction was imposed to help protect the workforce and also maintain safety for all road users within the narrower lanes," a spokesman said.
"Between 1 November 2010 and 3 February 2011 more than 900 drivers have been identified as committing motoring offences, mainly speeding.
"A further 26 vehicles were found to have serious defects, 11 vehicles were seized because drivers had no insurance or valid licence and four drivers were arrested, two of them for driving while disqualified.
"Officers were appalled by the high volume of offences when the patrols started.
"Speeding was the main problem but there were also many people driving while using mobile phones or not wearing seat belts."
Nearly 600 people have received fixed penalty notices and 149 drivers were dealt with by postal prosecutions because they were speeding in an area where it was not safe to stop, officers said.
Another 107 were given verbal warnings and 158 have been summonsed to court for breaking the speed limits or more serious offences.