At Kingston Mills Lockstation, the Cataraqui River descends from Colonel By Lake to the Cataraqui Estuary, over a series of rocky ledges. A high stone arch dam with a weir, is located across the original course of the river at the head of the falls. Long earthen dams on each side of the stone arch dam hold back the water of Colonel By Lake. The locks were built in a side channel west of the main channel of the river. The upper lock is attached to the south end of the stone arch dam. Below the upper lock, a large basin used for steamship repair still exists. The lower three locks are constructed in flight, with the lowest lock ending the canal at the level of Lake Ontario.
Four locks – One manually operated lock separated from the three locks in flight by a large turning basin. The locks have a combined lift of 14,8 m, 1830. CRM1.
Stone arch dam – A dam, 120 m long and 9 m high, with a weir on the north end, 1830. CRM1.
Two earth embankment dams – One on each side of the stone arch dam. The westerly dam is 800 m long, the easterly 600 m long, 1830. CRM1.
Weir – A masonry stoplog weir with one bay, 1830. CRM1.
Blockhouse – A two-storey building, the ground floor is stone, the second, frame, 1833. CRM1.
Lockmaster’s house – A small frame building, 1925. CRM2.
The Cataraqui River flows south from the lockstation under Highway 401 and through a large wetland (the Cataraqui Marsh), before it empties into Lake Ontario at Kingston (population 126 000).