Bydd y gwaith arfaethedig yn cynnwys:lledu ffordd yr A4138, gan leihau tagfeydd wrth i bobl ymuno â'r draffordd a'i gadaeldarparu cyfleuster i gerddwyr a beicwyr a rennir, gan gysylltu â'r llwybr a adeiladwyd yn ddiweddar rhwng yr A4138 ac Felinfoel a darparu cyswllt parhaus rhwng yr Hendy a Llangennechadnewyddu'r signalau traffig presennol a darparu signalau traffig newydd i wella diogelwch a lleihau ciwiaumesurau rheoli lonydd ar yr A4138 tua'r de, er mwyn manteisio i'r eithaf ar gapasiti'r ffordd bresennolgwelliannau i holl gyffyrdd yr M4 â'r A4138gwelliannau amgylcheddol i wella cynefin ar gyfer pathewod
The proposed works will involve:carriageway widening of the A4138, reducing congestion as people join and leave the motorwayprovision of a shared use pedestrian and cyclist facility, linking with the route recently constructed between the A4138 and Felinfoel and providing a continuous link between Hendy and Llangennechrenewal of the existing traffic signals and provision of new traffic signals to improve safety and reduce queueslane management measures on the A4138 southbound, to maximise the capacity of the existing carriagewayimprovements to all of the M4 junctions with the A4138environmental enhancements to improve habitat for dormice