 The construction of the Emerald Drive interchange was scheduled for the year 1971 . While the El Camino Real interchange was already a diamond interchange , the state planned to add traffic signals to the ramps to accommodate more congestion from the nearby mall . The Emerald Drive interchange was completed in September , and the rest of the project was to be completed by the end of the year , leaving Jefferson Drive as the only remaining traffic signal . Construction on the Jefferson Street interchange began in early 1972 ; the section from I @-@ 5 east to Melrose Drive ( along the routing of the Vista Way Freeway ) had been upgraded to full freeway standards as of 1973 . 
