HARRIMAN – Demolition of the New York State Thruway Authority’s Harriman toll plaza will begin Monday.

The authority’s contractor, Montesano Bros. of New Rochelle, will demolish the 13-lane toll plaza in phases in the coming weeks. Initially, there will be no changes in traffic patterns through the area.

This final element of the $13.9 million effort to convert the Harriman toll plaza to all-electronic tolling follows the activation of a temporary fix to meld the Thruway’s so-called “ticket” and “barrier” systems.

The fix is the construction of two new toll booths with cash and E-ZPass lanes to handle motorists exiting the southbound Thruway at Harriman, where the ticket and barrier systems begin or end. The booths began operation last week.

Since all-electronic tolling went live in September, these motorists had continued to use the two booths on the far right side of the toll plaza, adjacent to Woodbury Common Premium Outlets, pending construction of new ones closer to the exit.

The Thruway Authority completed the conversion of its barrier system to all-electronic tolling in December. The conversion of its ticket system, which covers most of the 570-mile highway, is scheduled for 2020.