TRAFFIC statistics from Laceby Bypass show that reducing speed limits does work, according to highways bosses.
When the limit along that section of the A46 was 70mph, 80,000 of the 115,000 vehicles which travelled down that road every week were going faster than 79mph.
But since introduction of a 50mph limit with speed cameras in October, 2009, just 4,000 of the 118,000 vehicles which travelled down that road every week were driving above 57mph.
Those speeds are the enforcement speeds for the respective limits of 70mph and 50mph.
The evidence was presented to North East Lincolnshire Council's Speed Limit Review Select Committee by road safety engineer Miguel D'Souza.
It came after Councillor Philip Jackson (Con, Waltham), expressed doubts that reducing the speed limit to 50mph on the A180 between the Pyewipe and Lockhill roundabouts would reduce the number of collisions on that stretch of road.
Mr D'Souza told the committee that there had been three fatal collisions along that section between January 2000 and December 2012 – all occurring at roundabouts.
But Councillor Jackson said: "If people aren't taking notice of the 30mph zone at roundabouts what are the chances of them taking any notice of a 50mph zone?
"It's a bit naive to think that dropping the speed limit to 50mph is necessarily going to make a significant difference to collisions."
However, Mr D'Souza said that there had been an 80 per cent reduction in collisions on the A46 since the introduction of the new speed limit.
But Keith Peat, East Midlands co-ordinator for the Alliance of British Drivers, accused the road safety industry of taking a "tunnel vision view" of accident statistics.
He said: "They say they have reduced collisions on a particular section, but how many collisions have they caused further down the road?"
The panel also heard from Gary Horth of Hull City Council, who described how the introduction of more than 150 20mph zones across the city had reduced the number of collisions in those areas significantly.
James Milligan-Manby, of the Country Landowners' Association, said the A18 had some "dodgy bends" but was not convinced a "blanket speed limit" would solve the problem.
The select committee will conduct a site visit of all the roads listed in the proposals on March 7, before publishing its recommendations.
