Ships Companies Ports Documents Distances FAQ Contacts Dominica Time: GMT -4. International dialling code: +1 809. Territorial waters: The Commonwealth of Dominica claims a limit of 12nm for territorial waters and a limit of 200nm for fisheries jurisdiction. Capital city: Roseau. PORT LATITUDE LONGITUDE REMARK UNCTAD TIME ZONE MAX DRAFT MAIN PORT DETAILS Portsmouth 15° 34.0' N 061° 28.0' W Port Open DMPOR GMT -4 3.35   Details Roseau 15° 18.0' N 061° 23.0' W Port Open DMRSU GMT -4 9.14   Details Woodbridge Bay 15° 19.0' N 061° 23.0' W Sub Port   GMT -4   Roseau Details