The route crosses the Rocky Gorge Reservoir and enters Howard County just beyond the northern end of the bypass. It intersects Old Columbia Road just beyond the reservoir and then upgrades into a six-lane grade-separated almost-freeway within its interchange with MD 216 at Scaggsville. Continuing as an almost-freeway, it interchanges with Johns Hopkins Road after two miles (3 km), then downgrades to four lanes again just before the Middle Patuxent River and intersects Rivers Edge Road at a half-signalled intersection. (Rivers Edge Road, which is the sole entryway into a subdivision containing over 300 homes, intersects the southbound carriageway, which has the signals; the northbound carriageway has a signalled turn lane and an unsignalled acceleration lane, both within the median.)