Cardiff -Portsmouth Engineering work 2026

[whole diary]

[John D]

Seems the Cardiff-Portsmouth service is having multiple interruptions due to engineering work this year.

Sun 1 Feb
suspended Salisbury - Southampton

Sat 7 - Sun 8 Feb
suspended Warminster - Salisbury

Sun 15 Feb, Sat 21 - Sun 22 Feb
Diverted via Eastleigh, not serving Southampton

Mon 16 - Fri 20 March & Sun 29 March
Only 2 or 4 tracks Newport-Cardiff, some timings changed, some trains not beyond Bristol

Sat 21 - Sun 22 March
suspended Bristol - Cardiff

Sat 2 - Mon 4 May
suspended Bath Spa - Westbury

Sat 23 May - Mon 8 June
suspended Bristol - Cardiff (provisional)

[John D]

National Rail has bit more info on the 3 day closure  early May
Bath - Chippenham / Westbury

Description
Engineering work is taking place between Chippenham and Bath Spa / Freshford, closing most lines.
Saturday to Monday:
An hourly train service will operate between:
London Paddington and Bristol Temple Meads via Bristol Parkway (not calling)
London Paddington and Chippenham via Swindon
Trains between Cardiff Central and Portsmouth Harbour will operate between Cardiff Central and Bath Spa (with most calling additionally at Keynsham and Oldfield Park) then between Westbury and Portsmouth Harbour.
Replacement buses will operate between:
Chippenham and Bath Spa
Bath Spa and Westbury
Bath Spa and Bradford-on-Avon

https://www.nationalrail.co.uk/engineering-works/bath-spa-2-may-20260502/

[Timmer]

There is also engineering work in the Bath area the weekend before 25/26 April:

https://www.gwr.com/travel-information/travel-updates/planned-engineering

Track and structural renewals work will impact train services between Bath Spa and Chippenham or Westbury.

Additional engineering work will also impact trains between Swindon and Westbury on Sunday 26 April until 1130.

Replacement transport is planned between:

Bath Spa and Chippenham, or Swindon
Bath Spa, Bradford-on-Avon, Trowbridge and Westbury, or Frome
Bath Spa, Freshford, Avoncliff and Bradford-on-Avon
Swindon, Chippenham, Melksham, Trowbridge and Westbury (until 1130 Sunday)
Trains will run hourly between London Paddington and Bath Spa via Bristol Temple Meads, with some trains running between London Paddington and Chippenham on Saturday only.

As a result, train services operating between London and South Wales will also be reduced.

GWR^▸ (Great Western Railway) will operate trains between Cardiff Central and Bath Spa instead of Portsmouth Harbour, or between Gloucester and Bristol Temple Meads instead of Frome or Weymouth.

Separate train services will be operating between Westbury and Portsmouth Harbour, Frome or Weymouth.

Trains also run on Saturday between Westbury and Swindon plus on Sunday after 1130, along with some additional train services between Chippenham and Swindon.

[John D]

In a piece of unfortunate timing for Bath-Westbury close 2-4 May appears to be the first of really busy cruise weekends at Southampton

Sat 2 May has 3 ships over 13,000 berths (double occupancy) over 17,000 (all berths) doing changeovers

Let's hope replacement buses have lots of suitcase room

[John D]

Further engineering work has been announced

No trains Fareham - Portsmouth
Saturday 28 March to Thursday 2 April (6 days)

Suspended in Southampton area Sat 11 April - Sun 12 April

Easter weekend Friday 3 April to Mon 6 April has a line closure St Denys-Eastleigh-Winchester, so the Southampton - Fareham - Havant area trains likely to be carrying diverted passengers too.

No trains Fareham - Portsmouth
Monday 25 May to Friday 29 May  (5 days)

No trains through Severn tunnel (diverted to Bristol Parkway)
Sat 22 May - Mon 8 June (17 days)
(so just Bristol-Parkway-Fareham 25-29 May)

So dozens of days in first half 2026 when line is not operating throughout, both weekends and weekdays

[John D]

Further info on upcoming work, seems the cast iron footbridge in Sydney Gardens, Bath will get scaffolding ahead of grit blasting.

Also going to do work on listed Eastern portal of Box tunnel (which few years ago they allowed vegetation to become established and damage some stonework

https://www.bathecho.co.uk/news/community/restoration-work-railway-bus-replacements-planned-116929/#google_vignette

[Mark A]

The state of play with that Sydney Gardens footbridge this afternoon, now encapsulated in its wrap. Not sure why Network Rail says it's the last survivor on the GWML^▸ (Great Western Main Line), I'd expect it to have been a bespoke bridge for the location.

I can clearly remember, at about the age of three or four, being taken to that bridge to get suitably filthy watching a procession of large and soot-besmirched locos roll beneath: quite a lot of their exhaust would envelop the bridge and some would make its way between the timbers of the deck. On the negative side, cinders in the eye really hurt and could be stubborn to remove.

Mark

[Image from here is not available to guests]

[Image from here is not available to guests]

[John D]

The plague of disruption due to engineering work continues on the line

Southampton to Portsmouth Sunday 5 July

(crazily spaced intervals few weeks apart so just as rail traffic builds up again and gets back to normal, there is another multi-day interruption discouraging usage)

Bath Spa to Bristol will be closed Monday 26 to Wednesday 28 October

Fareham to Portsmouth closed Monday 26 to Friday 30 October

Note strange inconsistency in the October work, one part of route is closed 3 days, other part 5 days.    And what's with mixture of weekend and weekday in Portsmouth area.   All rather feels gone out of their way to be passenger unfriendly

[John D]

Details of more closures now available affecting Cardiff - Portsmouth

Sat 13 - Sun 14 Sept suspended Southampton- Portsmouth

Sat 3 - Sun 4 Oct suspended Fareham - Portsmouth

Sat 10 Oct suspended Warminster - Romsey
Sun 11 Oct suspended Warminster - Southampton

Sat 17 Oct suspended Salisbury - Southampton
Sun 18 Oct suspended Warminster - Southampton

Sat 24 - Sun 25 Oct diverted Romsey - Fareham via Eastleigh

Mon 26 - Wed 28 Oct suspended Bath Spa - Bristol

So clearly weekends in the Autumn are going to be, take car instead.