The AA says controversial lower speed limits on rural Hastings roads place a "big cost" on the region but a senior policeman says a recent crash shows they can save lives.
Hastings District Council lowered speed limits on about 78km of roads in March but decided to review the changes after a public outcry.
Much of the criticism has been directed at speed reductions from 100km/h to 80km/h with motorist voicing frustration over increased travel times.
The council has received more than 1000 submissions on the changes and staff are currently analysing the feedback ahead of holding a hearing on the issue to be held on December 8 and 9.
In the Automobile Association's submission, the chairman of the organisation's Hawke's Bay District Council, Les Cunningham, said the time difference for a journey taken by a single vehicle at the lower limit may not seem large but "when this is multiplied over many thousands of vehicles, it becomes a big cost to the region that does not seem to have been factored into the council's decision to reduce speed limits".
Mr Cunningham's submission said the AA was concerned lowering the limits could actually increase safety risks because the organisation had observed drivers overtaking vehicles sticking to the 80km/h limits on the roads.
"Effective speed limits need to fit with human psychology and behaviour," he said.
"Frustrated drivers are more likely to make bad choices or take risks that could ultimately lead to worse safety outcomes on these roads."
But the officer in charge of Hawke's Bay's road policing group said in his submission to the council an accident on a stretch of road where the speed limit had recently been dropped to 80km/h would have resulted in two deaths if the limit had been kept at 100km/h.
Senior Sergeant Greg Brown said a July 31, smash at the intersection of SH2 and Pakipaki Rd, south of Hastings, where a truck pulled out in front of a car, would have been a double fatality if the car's driver had not been sticking to the 80km/h limit.
"Fortunately for the mother [driving the car] and her two children, she was travelling at the reduced speed limit.
"Although the collision was a heavy one, and the mother suffered serious abdominal injuries, the eight-year-old child in the front passenger's seat suffered moderate injury, and the toddler in the back was uninjured," Mr Brown said.
"Had they been travelling at the previous speed limit I have no doubt the mother and the eight-year-old would have died."
Mr Brown said the council should "put safety in front of minor inconvenience".