Beaver Dam is a city in Dodge County, Wisconsin, United States, along Beaver Dam Lake and the Beaver Dam River. The population was 16,291 in 2012, making it the largest city in Dodge County.
Beaver Dam was first settled by Thomas Mackie and Joseph Goetschius in 1841, and by 1843 had a population of almost 100. The city was named for an old beaver dam located in a stream flowing into Beaver Dam River. The area had also been known as Okwaanim, Chippewa for "beaver dam." The community was incorporated as a city on March 18, 1856. That same year the Milwaukee Railroad reached the area, encouraging further growth.
Beaver Dam is also home to the Williams Free Library (Dodge County Historical Society), the first public library in the United States to have open stacks.