Police are maintaining a strong presence by the newly opened First Lieutenant Derek S. Hines Memorial Bridge to ensure motorists adhere to speed limits on both sides of the span. Both the Newburyport and Amesbury police are have increased patrols, at least for a few weeks. The bridge, which connects Amesbury and Newburyport, reopened this month after being closed for nearly two years. The span is named for a Newburyport man who was killed on Sept. 1, 2005, while serving with the Army’s 319th Airborne Field Artillery Regiment in Afghanistan. Hines was 25. The bridge had been closed since November 2010 as workers replaced the original span with a new one. Reconstruction was necessary after a barge struck the bridge.