Construction is due to begin in the coming months on the first two of 12 bus corridors that are being built in the Greater Dublin Area as part of the BusConnects programme.
Eleven of the 12 corridors have been granted planning permission, with work on two of them - Liffey Valley to city centre and Ballymun/Finglas to city centre - due to begin in the coming months.
There have been significant local objections to some of the schemes, with five of them subject to judicial reviews.
However, BusConnects said it is confident that the corridors - which are a major part of the transformation of the services - will be completed by 2030.
Shankill is the latest area where a judicial review application has been sought against by An Bord Pleanála's decision to grant permission for a core bus corridor.
The suburb is just off the M11 - a motorway that connects Dublin with the southeast of the country - and is flanked by old stone walls and long lines of mature trees, much of which locals say will be lost under the plans.
Last week, local resident and Fine Gael councillor Jim Gildea was among those who made a court application to have the scheme reviewed
"I have been a councillor for 10 years and I have not known any single project that has had this amount of opposition," he said.
"Almost 3km of hedgerows, about 400 trees, all of the granite walls on either side will be removed.
"The whole fabric of the village, plus the surrounding area, will be just destroyed. The removal of the trees is just going to be an environmental disaster."
BusConnects has amended its original plans for the area and will no longer change the core of Shankill.
However, Mr Gildea said that it is not enough and alternative proposals that locals have put forward are being ignored.
The new bus lanes, he claimed, will cut just two minutes from the journey time through the area, adding the time cut would be much quicker if the M11 and N11 were used for bus journeys from Bray to the city centre.
"We have proposed to the National Transport Authority on numerous occasions that they would consider using the hard shoulder on the N11, which Transport Infrastructure Ireland themselves are planning to use for national bus services, and only buses that need to come to Shankill would utilise Shankill."
In Ballyfermot, businesses have also had issues with proposals for a core bus corridor.
Following a series of protests and community consultations, BusConnects agreed to amend parts of the plan and reduce the number of car parking spaces to be removed from outside businesses.
However, concerns remain, in particular about the loss of the Ballyfermot roundabout.
Des Sheils and his wife Jackie Moran have been running Jackie's Florist on Ballyfermot Road for 37 years.
Mr Sheils has been involved in talks with BusConnects to change the plans to reduce the impact on businesses and said that progress has been made.
"The original plans would have gotten rid of 90% of the parking spaces. It would have turned half the Ballyfermot Road into a one-way system, which would have impacted greatly on the residents and deliveries and shop owners as well.
"We're caught between a rock and a hard place that they already had full planning permission granted. We couldn't do a judicial review, because we just couldn't afford it.
"We were told it would to be about €150,000 so we just knocked that on the head and went the protest way. And they came around.
"We've had several meetings and they've come to see our point of view and we've seen their point of view, to a certain extent."
However, Ms Moran said she still believes the bus lanes will have a negative impact on the area.
"The impact will be very, very strong. Day-to-day business will not be the same, not just for me, for all the shops along this area and really the hub of Ballyfermot is the few shops we have.
"It's really crazy what they're trying to do. As it is, it's fine. We've got a great bus service, but what they're trying to do from Liffey Valley to get into town quick, it's not the answer, in my opinion.
"The Ballyfermot roundabout, if you ask anybody where they're going in Ballyfermot, everyone says the roundabout.
"It's part of our heritage and it's part of our culture. And if that goes, the heart of Ballyfermot goes."
Watch: Residents voice concerns as BusConnects says 'there will have to be compromises'
Twelve corridors that will be 230km long are to be built as part of BusConnects.
It said it accepts that there have been "challenges" with the project.
"We've worked very closely with the communities. Where there are opportunities for improving and making small refinements to public realm spaces, we have worked really well with them," Communications Manager Grainne Mackin said.
"Obviously, there are challenges. We do recognise that we are going to be taking some on-street parking, some trees and portions of gardens, and we've been very clear with people, and we're working very closely with them in terms of the CPO (compulsory purchase order) process around that.
"It can be challenging, and obviously there are people who have concerns about it, but we're working with a finite amount of physical space.
"In order for us to get in the safer cycling, the dedicated bus lanes, improving the footpaths and pedestrian areas, there will have to be compromises made."
Ms Mackin also said that the construction of the core bus corridors will bring traffic disruption but BusConnects is trying to balance the impact.
"The schemes, we anticipate, will take between 18 months and two years each to complete," she said.
"So in order to ensure that we keep the city moving, we plan on building approximately two schemes at any one time, maximum, maybe three, because we obviously are aware that there will be some congestion, there will be some traffic diversions and impact on people.
"However, people will start to see the benefits as we open each section of the new bus lanes and cycle lanes."
