Transport for Wales has said its services on the Coryton and Penarth lines haven't been good enough.
In a media release, the operator said delayed trains, trains being terminated early or cancelled altogether aren't delivering the service which customers deserve.
A statement said "We know that and we really are sorry. A dedicated group has been set up to look at the problems and find ways we can get back to the levels of reliability you rightly expect."
Transport for Wales has raised a number of key points which had led to train delays in Penarth and Coryton:
In June last year we developed a new timetable to get the best out of our brand new trains which are currently being rolled out. This new timetable links Coryton, Penarth and Caerphilly.
- Because of how many trains run on our Valleys Network, the turnaround time is very tight at both Coryton and Penarth. This means when one train gets delayed, it can very easily have a ripple effect on the trains behind it. TFW says it’s not easy to make that time back up, or ‘recover the timetable’ without causing further disruption.
- If the train is running very late it may mean terminating early such as at Ty Glas, or running fast past several stations to the end of the route in order to reset the situation. This works in terms of impacting the fewest people overall but we understand the impact it has on those using the stations we do miss.
- The new trains for the Coryton/Penarth/Caerphilly route are not quite ready yet. When they are introduced later this summer they will offer improved acceleration, greater capacity and more accessibility. With more carriages and more doors to board and alight from, which can save vital seconds and minutes getting trains into and out of stations. Over the course of a journey these small gains make a big difference.
"We brought the timetable in when we did so customers could get more of the benefits earlier, rather than waiting for all the new trains to be in place. It also meant we could get used to the new operating structure and identify any changes that needed to be made."
"While most of the routes have seen improvements, this is one area we need to work on."
Transport for Wales has committed to making improvements through a dedicated group, and has committed to:
- Introducing a new plan from 24 March that will see these services run fast between Caerphilly and Cardiff Queen Street. This will create more recovery time in the schedules and create a fast service into Cardiff for Caerphilly customers. While we will be taking out stops at Lisvane, Llanishen and Heath High Level as these are connected to the Coryton line, these stations still have four trains per hour in each direction. This will be on a trial basis.
- We commit that if we have to run a train fast in one direction, we’ll make sure it stops in the other direction. So if a train is running late onto the Coryton Branch we miss the stops on the up journey to Coryton but ensure the service calls at all stops on the down journey from Coryton.
- We commit that we will improve our information to customers and provide this in a timely fashion.
- We commit to protect some key trains at school times and morning/evening commutes.
- We commit to listen and remain open to specific ideas.
- We commit to maintaining our service on the Penarth line and to deliver performance improvements through our working group.

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