Two range light towers, known as Île Deslauriers Range, were placed in operation on May 1, 1902. The following description of the range lights was published by the Department of Marine:
The front light, erected on the east shore of Ile Deslauriers, is fixed white catoptric, elevated 37 feet above the summer level of the river, visible eleven miles from all points of approach in the channel, and is shown from a square wooden tower with sloping sides, surmounted by a square wooden lantern, standing upon a cribwork pier. The pier and tower are white and the lantern roof red. The height of the tower from the pier to the ventilator on the lantern is 19 feet.
The back light, erected on the east shore of Ile Ste.Therese, and distant 9,430 feet, S. 51° 15’ W. from the front light, is fixed white catoptric, elevated 73 feet above the summer level of the river, visible fourteen miles in, and over a small arc on each side of, the line of range, and is shown from a square tower, with sloping sides, consisting of an open steel framework, painted brown, surmounted by a wooden watchroom painted white, and topped by a square wooden lantern, painted red. The height of the tower from the ground to the ventilator on the lantern is 65 feet.
These lights, as well as the three pairs of range light towers last described [Verchères Village, Verchères Traverse, and Île Bouchard], were erected by day’s labour, under the foremanship of E. Roy. All are on sites subject to overflow in the spring, and all are therefore built on concrete pier foundations, which increased the cost of construction. The expenditure in connection with the erection of the eight lighthouses was $9,859.15.
The lights of Île Deslauriers Range shine upstream and indicate the axis of the channel from Verchères Point to Cap St. Michel Curve.
In 1907, a new four-section, skeletal, tower, purchased from the Goold, Shapley & Muir Company of Brantford, Ontario for $668.5 replaced the original three-section tower that housed the rear light for Île Deslauriers Range. This new tower stood eighty-two feet tall, from base to vane, and increased the focal plane of the rear light from seventy-three to eighty-nine feet. To enhance its visibility during the day, the square, pyramidal tower was outfitted with white, wooden, slatwork installed beneath the enclosed watchroom and lantern room on the side of the tower facing the range line. Day’s labour erected the new tower at a cost of $704.76, and the old tower was taken down to be used elsewhere.
The front range light was carried away by ice in 1926 necessitating the erection of a replacement tower set atop a square, concrete pier. The new tower was described as having an aluminum-colored, square watchroom with a red roof, and it exhibited a fixed white light at a focal plane of forty-feet, three feet higher than its predecessor.
At some point between 1955 and 1994, a twenty-nine-foot-tall, white, circular tower was installed to exhibit the front range light, but this was replaced in 1997 by a skeletal tower. Île Delauriers Range remains active today with skeletal towers used for displaying both the front and rear range light.