Mimico began slowly to decline as the children of families who lived in the small houses of the 1940s moved to the growing outer suburbs and the apartments did not live up to the hopes they had generated as they quickly deteriorated. Businesses also continued to fail and many of the small industries moved out. In 1984, Etobicoke became a city and a plan was prepared to rejuvenate Mimico which called for limiting the amount of commercial space by rezoning Mimico Avenue as non-commercial. The same year, Humber Bay Park was opened, consisting of two artificial peninsulas on either side of the mouth of Mimico Creek, with one on the east side and one on the west side (enclosing Mimico's beach to create a harbour) which connect to the main land at the end of Mimico Creek. The creation of the artificial park led to unintended consequences with some of the sandy shoreline in Mimico eroding away.