More than 600 people were caught speeding during National Slow Down Day yesterday.
The 24-hour operation is aimed at reducing road deaths caused by speeding.
The joint campaign by Gardaí and the Road Safety Authority (RSA) came after over 70,000 people were caught breaking speed limits in the year to July.
Superintendent Liam Geraghty told Newstalk Breakfast the numbers of people speeding remains high.
"In excess of 600 people yesterday were fined with fixed charge notices for breaking the speed limit," he said.
"Speeding is still a big problem and it is the big driver that causes the impact when you have a road traffic collision and causes deaths and serious injuries on our roads.
"It remains a high figure - particularly in a day which we advertise in advance and tell everybody that we will be out doing high-speed enforcement".
Supt Geraghty said one instance saw a driver pushing 177 km/h in a 120 km/h zone.
"Some of the examples of speeds [we caught] we have a driver at 177 km/h in a 120 km/h zone on the M6 in Westmeath," he said.
"[We caught] a driver at 141 km/h in a 100 km/h zone on the N4 also in Westmeath.
"A bigger concern, actually, is some of the figures around 50 km/h zones where we regularly have people 25 and 30 km/h in excess of the speed limit.
"We know those are the zones where there are far more vulnerable road users [such as] pedestrians, pedal cyclists [and] scooter users."
'Particularly bad year'
Supt Geraghty said speed is a big factor in road deaths.
"Somebody struck by a vehicle at 60 km/h has a nine in 10 chance of being killed," he said.
"A slight glimmer of hope is that the level of fatalities on our roads seems to have moderate to a certain degree so far this year.
"We are still at about 127 fatalities on our roads so far - that's on par with this time last year which unfortunately was a particularly bad year.
"It's still not great news but it is moderating".
Supt Geraghty said he believes drivers can speed as they have "a great sense of security" in their vehicle and probably don't realise they are travelling as fast as they are.
He added that there is a "fallacy" around speeding to get somewhere quicker - questioning how much time people actually make up by driving faster.
