M4 Motorway & A470 Trunk Road - Temporary Prohibition Of Vehicles For Works

HYSBYSIAD STATUDOL
I gael copi print bras o’r Hysbysiad hwn, ffoniwch 0300 0604400 neu ebostiwch Trafnidiaeth.YGangenOrchmynion@llyw.cymru  

GORCHYMYN TRAFFORDD YR M4 A CHEFNFFORDD YR A470
(CYFNEWIDFA CORYTON, CAERDYDD I GYLCHFAN CEFN COED, MERTHYR TUDFUL) (GWAHARDD CERBYDAU A BEICWYR DROS DRO) 202-

MAE GWEINIDOGION CYMRU yn bwriadu gwneud Gorchymyn o dan adran 14 o Ddeddf
Rheoleiddio Traffig Ffyrdd 1984 ymhen dim llai na 7 niwrnod i ddyddiad yr Hysbysiad hwn. 

Mae angen y Gorchymyn er mwyn gwneud gwaith ar draffordd yr M4 a chefnffordd yr A470, neu gerllaw iddynt, rhwng Cyfnewidfa Coryton, Caerdydd a Chylchfan Cefn Coed, Merthyr Tudful.

Effaith y Gorchymyn arfaethedig fydd gwahardd dros dro bob cerbyd (ac eithrio’r rhai a ddefnyddir gan y gwasanaethau brys neu ar gyfer y gwaith) a beicwyr rhag mynd ar y darnau o draffordd yr M4, ac ar hyd ddarnau penodol o gefnffordd yr A470 pan fo’n ofynnol gwneud gwaith ar safleoedd penodol, rhwng Gylchfan Coryton a Chylchfan Cefn Coed, fel y’u disgrifir yn yr Atodlen i’r Hysbysiad hwn. Disgrifir y llwybrau eraill yn yr Atodlen honno hefyd.

Daw’r Gorchymyn i rym ar 1 Gorffennaf 2026. Disgwylir y bydd y gwaharddiadau dros dro yn weithredol yn ysbeidiol dros nos (20:00 – 06:00 o’r gloch) o’r dyddiad hwnnw am gyfnod o 18 mis ar y mwyaf. Arddangosir hysbysiad ynghylch y gwaharddiadau tuag un wythnos cyn bod angen cau darn penodol o’r ffordd.

C WYNN, Trafnidiaeth, Llywodraeth Cymru

YR ATODLEN
Y darnau o ffyrdd ymadael neilltuedig tua’r dwyrain a thua’r gorllewin yr M4 wrth Gyffordd 32 (Coryton), sy’n arwain at yr A470 tua’r gogledd.

Y darn o gefnffordd yr A470, gan gynnwys yr holl ffyrdd ymuno ac ymadael o Gyfnewidfa Coryton, Caerdydd i Gylchfan Cefn Coed, Merthyr Tudful.

Ffordd gyswllt neilltuedig yr A470 o’i chyffordd â phrif gerbytffordd gylchredol Cyfnewidfa Coryton i’w chyffordd â phrif gerbytffordd tua’r de cefnffordd yr A470.

Llwybrau eraill
Codir arwyddion priodol i nodi’r gwyriad ar gyfer y llwybrau eraill a byddant yn amrywio gan ddibynnu ar ben y daith a phryd y bydd darn penodol o’r M4 a’r A470 a ddisgrifir uchod ar gau dros dro i draffig.

Mae llwybrau eraill ar gael drwy fynd ar yr A4054, A473, A472, A465, A468, A4060, A470, A4058 a’r B4275, fel y bo’n briodol.

STATUTORY NOTICE
For a large print copy of this Notice contact 0300 0604400 or email Transportordersbranch@gov.wales 

THE M4 MOTORWAY & A470 TRUNK ROAD 
(CORYTON INTERCHANGE, CARDIFF TO CEFN COED ROUNDABOUT, MERTHYR TYDFIL) 
(TEMPORARY PROHIBITION OF VEHICLES & CYCLISTS) ORDER 202-

THE WELSH MINISTERS propose, in not less than 7 days from the date of this Notice, to make an Order under section 14 of the Road Traffic Regulation Act 1984, which is necessary to undertake works on or near the M4 motorway & A470 trunk road between Coryton Interchange, Cardiff and Cefn Coed Roundabout, Merthyr Tydfil. 

The effect of the proposed Order will be to temporarily prohibit all vehicles (other than those being used by the emergency services and for the works) from proceeding on the lengths of the M4 motorway, and over specific lengths of the A470 trunk road when work at a particular site is required, between Coryton Roundabout and Cefn Coed Roundabout as described in the Schedule to this Notice. The alternative route arrangements are also described therein.

The Order will come into force on 1 July 2026. The temporary prohibitions are expected to operate intermittently overnight (20:00 – 06:00 hours) from that date for a maximum duration of 18 months. Notice of the prohibitions will be displayed approximately one week before the closure of a particular length of road.

C WYNN, Transport, Welsh Government

SCHEDULE
The lengths of the M4 eastbound and westbound dedicated exit slip lanes at Junction 32 (Coryton), leading to the northbound A470.

The length of the A470 trunk road, including all entry and exit slip roads from Coryton Interchange, Cardiff to Cefn Coed Roundabout, Merthyr Tydfil.

The dedicated A470 link road from its junction with the main circulatory carriageway of Coryton Interchange to its junction with the main southbound carriageway of the A470 trunk road.

Alternative routes
The alternative routes will be signed with appropriate diversion signs and will vary depending on destination and when a particular length of the M4 and A470 within the above description is temporarily closed to traffic.

Alternative routes are available via the A4054, A473, A472, A465, A468, A4060,
A470, A4058 and B4275, as appropriate.