Waterloo is a city in Linn County, Oregon, United States. The population was 229 at the 2010 census.The city's name, a joking reference to the Battle of Waterloo, stemmed from a 19th-century court decision that settled a land dispute at Kees Mill along the South Santiam River. After the dispute ended, Kees Mill became known as Waterloo.The federal government established a post office at Waterloo on January 5, 1875. S. D. Granger was its first postmaster. The post office closed in 1974.GeographyAccording to the United States Census Bureau, the town has a total area of 0.12sqmi, all land. The closest city is Lebanon.ClimateThis region experiences warm and dry summers, with no average monthly temperatures above 71.6F. According to the Köppen Climate Classification system, Waterloo has a warm-summer Mediterranean climate, abbreviated "Csb" on climate maps.Demographics2010 censusAs of the census of 2010, there were 229 people, 79 households, and 62 families residing in the town. The population density was 1908.3PD/sqmi. There were 87 housing units at an average density of 725.0/sqmi. The racial makeup of the town was 96.5% White, 1.3% Native American, 0.4% from other races, and 1.7% from two or more races. Hispanic or Latino of any race were 5.7% of the population.
