Catholic and independent schools across Canberra have raised concerns that the loss of some dedicated school buses will endanger young students, as they will be forced to "mix" with public commuters.

Key points: 49 dedicated primary school buses are earmarked to be scrapped

49 dedicated primary school buses are earmarked to be scrapped Figures show just eight primary school students are on each affected bus

Figures show just eight primary school students are on each affected bus Transport Canberra says most primary school students already use the regular network

St Mary MacKillop College principal Michael Lee said schools had been urging parents to express their concerns before consultation closes.

"My community is really concerned and has heightened anxiety about the safety of kids under the new bus route," he said.

"We have 14 dedicated bus routes to this school every morning and afternoon — under the proposed changes we will have five."

But Transport Canberra has defended the move, saying that more than half of primary school students who travel by bus already safely ride on the regular network.

Figures compiled by Transport Canberra, and seen by the ABC, showed, on average, there were just eight students catching each of the 49 dedicated primary school buses slated to be scrapped.

Estimates from MyWay ticketing data indicated about 1,160 primary school students used regular network buses and 840 used dedicated school buses.

About half of those on dedicated buses would be forced onto the regular network under the proposed redesign.

'Our dedicated buses aren't great': Transport Canberra

Transport Canberra boss Duncan Edghill said many of the existing dedicated school buses were part of legacy decisions that no longer made sense.

"We've seen our dedicated school bus network evolve over many years now, and where we've ended up is something that we think is sub-optimal, both for school students but also for the broader travelling public," he said.

"Our dedicated school bus services at the moment aren't particularly great."

Mr Edghill said the new network would see 30 per cent more buses servicing schools and more students within walking distance of a 'Rapid' express bus service.

Figures show, on average, just eight primary school students are on the buses earmarked to be scrapped. ( ABC News: Jake Evans )

"If we allow any part of our network to grow in a way that doesn't have regard to the totality of what we're doing, we can find ourselves in a situation where we're not using the finite resources that we have as efficiently as we can," he said.

In March the ABC reported that fewer than 75 per cent of ACTION buses arrived on time in any week over the past year, excluding Christmas and New Year's.

Mr Edghill said buses ran late, in part, because of long circuitous routes that had some students travelling an hour and a half to get to school — something the new network had been designed to solve.

Principals 'not reassured' by agency's safety message

But some school principals said their concerns lay with the safety of students who would be moved onto the regular bus network.

On Monday, Radford College principal Fiona Godfrey wrote to parents that the school would lose two of its six dedicated buses, despite repeated requests for more.

She said students would be forced to wait at "unsafe" bus interchanges and "mix with members of the public … with no supervision".

"It will not be practical or safe for Radford College Junior School students," Ms Godfrey wrote.

Other schools, such as St Clare's College and St Edmund's College in Canberra's inner south, raised concerns that students would now have to cross busy roads like Canberra Avenue to catch the bus.

St Mary MacKillop College principal Michael Lee is concerned for the safety of students. ( ABC News: Jake Evans )

And St Mary MacKillop College principal Michael Lee said a meeting on Tuesday between principals and Transport Canberra left him with more questions than answers.

"Under the proposed changes [students will] have to find their way to a bus stop, which is not necessarily in a school zone, which will not be supervised by a teacher and in fact could be on a major road like Ashley Drive that is 80 kilometres an hour," Mr Lee said.

"Tell me that's safe and I'll stop supervising the kids now."

Mr Lee said the message from Transport Canberra was not reassuring.

"When the gentleman running the meeting said 'I travelled on buses and trains when I was a school boy in Sydney and it was fine' — we're in a different space and a different time, and we know more now, and I'm not sure that's been taken into account," he said.

But Mr Edghill said Transport Canberra was "alive" to safety concerns and had already taken on suggestions from parents, such as introducing 'buddy benches' at interchanges for students who feel unsafe.

He said new infrastructure and more transit officers at stations would be considered in light of feedback given through their consultation period, but defended the safety of Canberra's bus interchanges.

"There are thousands of students per day who are actually changing at our interchanges between buses already," Mr Edghill said.

Consultation on the proposed new network closes on Sunday.