NY 47 was officially extended on both ends on January 1, 1970, to terminate at Lake Ontario on opposite sides of Rochester. In Greece, the designation officially followed what is now NY 390 north to the Lake Ontario State Parkway; however, the portion between US 104 and the parkway had yet to be constructed. To the east in Irondequoit, NY 47 was stretched northward along the Sea Breeze Expressway to Culver Road, resulting in overlaps with both US 104 and NY 18. At the time, the overlap with US 104 existed only between Empire Boulevard and the Keeler Street Expressway, which became the new alignment of the route through Irondequoit after its completion in 1969. The overlap with US 104 was eliminated entirely the following year when that route was realigned onto a new expressway alignment between NY 47 and Webster that traversed Irondequoit Bay via the newly built Irondequoit Bay Bridge. The overlap with NY 18 was eliminated when NY 18 was truncated to its current eastern terminus in Kodak Park.