 A new interchange with Vista Village Drive was opened in 1998 , and the College Boulevard interchange in Oceanside was revised along westbound SR 78 , at a cost of $ 5 @.@ 5 million ( about $ 9 @.@ 32 million in 2015 dollars ) . In addition to this , a new interchange was constructed at Las <unk> Road in San Marcos , which opened in 2006 . According to the U @-@ T San Diego ( the renamed San Diego Union @-@ Tribune ) , SR 78 at Barham Drive was the worst " traffic bottleneck " in the county between 2010 and 2012 . Thus , the interchange at Nordahl Road was also improved , and extra lanes were to be added between Nordahl Road and I @-@ 15 ; construction commenced in early 2012 , and the new bridge opened in November . The project cost $ 41 million . 
