Cedar Creek is a 53-kilometre-long (33 mi)^[1] stream in southeastern Wisconsin in the United States. The Cedar Creek watershed is a 330 km² (127 mi²) sub-basin of the larger Milwaukee River watershed.^[2][3]

Cedar Creek originates from Big Cedar Lake in the Town of West Bend and flows east into Little Cedar Lake. It then flows east through Jackson before turning south, crossing State Highway 60 where there is a USGS gauge^[4] and briefly flows through Grafton before entering Cedarburg's north side. The creek flows through downtown Cedarburg, and empties into the Milwaukee River southeast of Cedarburg in the Town of Grafton. The lower section through Cedarburg is notable for its the steep slope, and early settlers made use of this by building several mills and accompanying dams.^{[citation needed]}

The lower portion of the creek through downtown Cedarburg until its confluence with the Milwaukee River is impacted by the milldams and PCB pollution produced by Mercury Marine and Amcast automotive.^[5] Numerous cleanups have occurred, including a 2018 cleanup from the Cedarburg Mill's pond to the Cedarburg Wire and Nail Factory dam was completed in 2018.^[5]

Several mills dammed the lower portion of Cedar Creek in the mid and late 19th century. The mills proved successful and had large impacts on the local economy. By the early 20th century many of the mills had moved away from hydropower to more reliable steam or electric power.^[6] Financial trouble for the mills began during the Great Depression and continued into later decades as larger mills and factories outcompeted the small mills. By the late 1960s, all the mills had either ceased operations, and some buildings have been converted to commercial uses, while others were abandoned unused or demolished.^{[citation needed]}

Cedar Creek is normally a small low discharge stream, however like many streams it experiences regular flooding. In 1881, a sudden spring melt caused severe flooding that washed out all the dams on Cedar Creek except the one at the Cedarburg Mill. The flood also washed away at least one bridge.^[6] Large floods occurred in 1952, 1959, 1960, and 1975.^[7] In 1996, flooding washed out the dam at the Concordia Mill. Its millpond contained PCBs, and the washout complicated the cleanup by sending PCBs downstream.^{[citation needed]}

43°20′23″N 88°13′22″W / 43.33972°N 88.22278°W / 43.33972; -88.22278