Sixty thousand extra cars take to Dublin's roads this morning as the parents of returning primary and secondary school children join the traffic queues.
"The schools being back makes a colossal difference to the traffic," said the Dublin Chamber of Commerce director of policy, Mr Declan Martin. "In the morning peak, one in five cars on the road is bringing kids to school."
Mr Martin estimates the extra traffic will add about 20 minutes on average to the typical commuter's journey. Teachers returning to work account for a "huge amount" of the extra traffic, he said.
"All schools provide car parking for the teachers, when they should be putting in measures to encourage teachers to use public transport." This encouragement, he said, could come in the form of free public transport passes for commuting teachers. "There's no reason why the Department of Education couldn't put this into the remuneration package for teachers."
The chamber of commerce has made a submission to the Dublin Transport Office to introduce more school bus schemes for the city, Mr Martin said. "There are virtually none at the moment, but if schools can establish a reasonable catchment area along more populated routes they should be entitled to a school bus." Many parents, he said, would not put their children on public transport. "You can't send small kids on buses full of workers, they need a supervised school bus and we hope to see it introduced on a trial basis during this academic year."
Mr Martin also suggests bus corridors be made available to multiple-occupancy vehicles bringing children to school. "If cars with three or more passengers were allowed to use the quality bus corridors this would encourage parents to share lifts."
Dublin Corporation's director of traffic, Mr Owen Keegan, said these were not practical solutions to the traffic problem.
"There are enforcement issues with allowing ordinary cars to use the bus lane. The gardai would have to stop cars and count the number of passengers.
"This wouldn't be practical and the quality corridor that was available to buses would deteriorate."
He also claimed the widely dispersed catchment areas of Dublin schools would cause problems for a school-bus system. "If everyone went to the local school it wouldn't be a problem, but there's a huge amount that don't, and on that basis it would be very hard to provide a dedicated bus service."
While there was a deterioration in traffic at this time of year, Mr Keegan said, it was not "the norm" for children to be driven to school. "Seventy per cent of schoolchildren walk, take the bus or cycle to school. The reality is school kids conform much more closely to the recommendations on travel than the general population."
The location of schools on main thoroughfares has caused a lot of problems, he said, particularly when the schools allowed parents to park in the immediate vicinity.
"Even when there are markings showing it's illegal to stop, parents ignore them. Personally I would ban all parking in the vicinity of schools for the safety and health of the children."
The INTO general secretary, Senator Joe O'Toole, said it was unfair to blame schools for the traffic problem, but traffic was a concern for everyone.
"In that context, perhaps parents could look at car-sharing, staggering the time they go to work, or ask themselves if their journey by car is really necessary."