Er mwyn gwneud y gwaith hwn, bydd angen cau'r gerbytffordd tua'r gorllewin yn llawn yn yr ardal. Bydd gwrthlif yn weithredol lle bydd un lôn ar agor i'r ddau gyfeiriad 24 awr y dydd, 7 diwrnod yr wythnos am hyd at bum wythnos. Mae angen gosod yr wyneb diddos mewn tywydd gweddol a dyma'r rheswm yr amserlennwyd y gwaith ar gyfer y cyfnod hwn. Bydd yr holl waith wedi'i gwblhau erbyn canol dydd ar 18 Hydref fan bellaf, sef cyn i'r ysgolion ddechrau eu gwyliau hanner tymor.
This work requires a full closure of the westbound carriageway in the area with a contraflow in place which will see a single traffic lane in each direction 24/7 for up to five weeks.  The waterproofing needs to be laid in reasonable weather conditions which is why it has been programmed to take place during this period. All work will be completed by midday on 18 October at the very latest, which is before the beginning of the half term holidays.