A lighthouse on Grande Île Kamouraska was proposed in 1846, along with a lighthouse on Île Rouge, to help prevent the lamentable accidents which so frequently occurred along that stretch of the St. Lawrence River. Île Rouge Lighthouse went into operation in 1848, but it wasn’t until 1860 that funds were provided for a lighthouse on Grande Île Kamouraska along with lights at four other sites: Brandy Pots, Long Pilgrim Island, Bellechasse Island, and Crane Island. Eleven tenders for the work were received, and a contract for constructing all five lighthouses was awarded to Louis Dery, a builder of Quebec.
The necessary lanterns and lighting apparatuses were ordered from England, and Louis Dery spent the winter of 1860 – 1861 assembling the necessary materials for the project. In May 1861, the Chief Engineer of the Department of Works and an experienced river pilot examined the five islands proposed for the lights and selected building sites. Three of the lighthouses were completed in 1861, including the one on Grande Île Kamouraska, and the following description of Grande Île Kamouraska Lighthouse was published.
The light house at this place is about 1,200 feet from the north-eastern extremity of the island, and the site 130 feet over the water. The tower is a square, of wooden frame-work, 27 ½ feet high, and connected with it, on the west side, is a house for the keeper. The lantern is octagonal, and provided with 7 lamps and 7 reflectors … which illuminate 225 degrees of the horizon. The centre of the light will be 162 feet above the level of the sea.
A keeper was selected for the mineral-oil-burning lamps and properly trained, so that the lighthouse was ready to be placed in operation at the opening of navigation in 1862.
A new lantern room and lighting apparatus were placed atop Grande Île Kamouraska Lighthouse in 1876 at a cost of $1,813.19, changing the light’s characteristic from fixed white to flashing white. The lighting apparatus had two No.1 circular-wick lamps with twenty-two-inch reflectors on each of its two faces, and completed one revolution in a minute-and-a-half in order to produce a white flash every forty-five seconds. Due to the extra work required by the revolving light, the annual salary of Keeper Thomas Roy Desjardins was raised from $350 to $400.
As the introduction of steamships increased the speed at which vessels passed the lights along the St. Lawrence, it became necessary to reduce the interval between flashes at some of the lighthouses. At the opening of navigation in 1894, the period of revolution used at Grande Île Kamouraska was changed from ninety seconds to one minute, meaning that mariners would now see a flash every thirty seconds instead of every forty-five seconds. In 1915, a fourth-order lens was installed in the lantern room, changing the light characteristic to a white flash every seven seconds.
A new dwelling was built on the island in 1912, under a $3,600 contract awarded to Lachance & Fils of Fraserville, Quebec.
Grande Île Kamouraska Lighthouse was demolished in 1982 and replaced by a modern beacon that flashes every six seconds atop a skeletal tower.
Head Keepers: Thomas Roy Desjardins (at least 1866 – 1887), Jean B. Desjardins (1887 – 1901), Arthur Levesque (1901 – 1913), J.B. Desjardins (1913 – 1920), L. Albert (1920 – 1921), A. Leclerc (1921 – 1934), J.D.A. Goselin (1934 – 1936), A. Roy (1936 –1937), August Langelier (1937 – 1961).