The Carrum Carrum Swamp encompassed 52 square kilometres with a catchment area of 735 square kilometres. It had four outlets to the Port Phillip Bay, including Kananook Creek/Eel Race Drain, Patterson River and Mordialloc Creek. Explorer William Hovell discovered "a very extensive fresh water marsh, from 12 to 15 miles long and 11/2 to 6 broad, and only separated from Port Phillip by a narrow ridge or bank of sand not more than from two hundred to three hundred yards wide." A painting titled “Lagoon in the Carrum Carrum Swamp – evening 1872” by James W Curtis is held at the National Gallery of Australia.
The Carrum Carrum Swamp was drained in 1879 when the Patterson Cut (formed in 1876), and other drainage measures were undertaken to prevent flooding of the Eumemmering Creek, which overflowed into the swamp. When the Patterson Cut was dug, the area that is now occupied by Patterson Lakes was turned to farmland with mainly dairy cattle. By the late 1960s farming activities had just about ceased, and the area became popular with fox and rabbit shooters.
Coordinates: 38°04′S 145°07′E / 38.067°S 145.117°E