The nearly seven-mile-long Contrecoeur Channel includes four straight sections, 12,800-foot-long St. Ours Traverse, 5,500-foot-long Petite Traverse, 10,200-foot-long Contrecoeur Course, and Contrecoeur Traverse, which are joined by gentle curves or bends.
To mark this improved channel, the Department of Marine rearranged the buoys it maintained along this section of the river and erected new range lights to equip the channel for night navigation. On October 27, 1903, three sets of range lights were established to guide mariners along the St. Lawrence River north of Contrecoeur and east of Île Saint-Ours: St. Ours Traverse Range, Petite Traverse Range, and Contrecoeur Course Range. (A new range was activated on July 15, 1904 to mark Contrecoeur Traverse.)
The front towers and rear towers used on the three ranges were similar. The front towers consisted of thirty-three-foot-tall, square, wooden, structures, with sloping sides and surmounted by a square lantern room, while the rear towers were square, steel, skeletal structures topped by an enclosed watchroom and a square, wooden lantern room. White slatwork was mounted on the side of the rear tower facing the range line for improved visibility during the day.
The following description of Contrecoeur Course Range was published shortly after the lights were placed in operation on October 27, 1903 to mark the axis of the cut in the improved ship channel known as Contrecoeur Course:
The front tower stands on the ground on the crest of the river bank east of St. Ours traverse, 155 feet from the position occupied by the day beacon which it replaces, and 4275 feet N. 8 48' E. from the front tower of the Petite Traverse range. The light is elevated 63 feet above the level of the river.
The back tower stands in the fields, 75 feet S. 40° 30’ E. from the position previously occupied by the day beacon which it replaces, and 2555 feet N. 48° 15’ E. from the front tower. The light is elevated 127 feet above the level of the river.
The two lights in one astern lead through Contrecoeur course in the axis of the ship channel S. 48° 15’ W. from Contrecoeur bend to the bend at gas buoy No. 43 M.
Joseph Arpin was hired as the first keeper of the front light at an annual salary of $100, while Norbert Duval was paid the same amount to look after the rear light.
At some point between 1955 and 1994, the present towers that serve Contrecoeur Course Range were erected and the characteristic of the light was changed from fixed green to fixed yellow. The current front tower is a sixty-three-foot-tall, square, skeletal tower that displays its light at a height of eighty-five feet above the river, and the rear tower is a seventy-seven-foot-tall, tripod, skeletal tower that displays its light at a height of 138 feet. The range lights are now listed on the official Canadian Coast Guard Light List as Route de Contrecoeur Range. The original front tower remains standing near the modern front range light.