State Sen. Nick Collins is confident that changes to the security plan will prevent a repeat of last year's scene at the St. Patrick's Day parade.

All streets have been reopened to car and pedestrian traffic, as Boston’s famed St. Patrick’s Day parade came to an end Sunday afternoon.

Throngs of green-clad, shamrock-festooned revellers filled the streets of America’s most Irish big city on Sunday for the South Boston St Patrick’s Day parade. Green, white and orange confetti – the national colours of the Emerald Isle – rained down along parts of the three-and-a-half-mile (5.