By 1917, when the following description of the Ange Gardien Range Lights appeared in the U.S Hydrographic Office’s The Gulf and River St. Lawrence, the rear light at Ange Gardien Range was also being displayed from an enclosed tower:
A square white lighthouse, with a red roof, 23 feet high, on the beach between l’Ange Gardien village and Montmorency Falls, on the mainland, northwestern shore, exhibits, at 20 feet above high water, a fixed white light that should be seen, in clear weather, a distance of 9 miles.
A square white lighthouse, with a red roof, 21 feet high, situated 26°, 473 yards from the preceding lighthouse, exhibits, at 33 feet above high water, a fixed white light that should be seen, in clear weather, a distance of 11 miles.
These lights in line 26° lead clear of all obstructions from intersection with Ste. Famille range to junction of Orleans channel with South channel opposite west point of Orelans island.
Ambroise Trudelle and Joseph Huot were hired as the first keepers of the Ange Gardien Range Lights, and each earned an annual salary of seventy dollars.
The lights of Ange Gardien Range were changed from fixed white to fixed green in 1951 or 1952, and at this time the original towers were still in use. By 1994, forty-four-foot-tall, square, skeletal towers had been erected for exhibiting the range lights, and similar structures remain in use today. The characteristic of the lights remains fixed green.