This is the process by which a property or group of properties outside of, but adjacent to, the boundaries of the City of Wausau becomes part of the City. It is the primary means of physical growth for the City. The annexation process is established and regulated by State Statutes. In its simplest form, the process begins when a majority of the owners of property in an area adjacent to the City submit a written petition requesting that their property become part of the City of Wausau. People choose to annex for a variety of reasons, the most common of which is to obtain municipal sanitary sewer and water services. Generally, annexations need to conform to the City’s sewer service area or growth management plan.
Almost all of the City’s population growth since 1960 can be attributed to the annexation of developed and undeveloped land. From 1960 to January, 2006, the City annexed over 7,253 acres of land from the adjacent unincorporated towns. This represents 11.3 square miles. During this 46-year period, an average of 1,600 acres per decade were incorporated into the City of Wausau, or approximately 160 acres per year. This 46-year period of growth has moved the City’s western boundary from approximately 12th Avenue to beyond 84th Avenue and a portion ot the City's eastern boundary to 41st Street. Much of the new development within the USH 51 and STH 29 corridors has been established on territory annexed to the City. This includes the Wausau Insurance Companies complex, Aspirus Hospital, many of the medical clinics in this area, the 17th Avenue and Stewart Avenue commercial complexes, and Wausau West Business and Industrial Park.
In addition to the huge area devoted to commercial, industrial and institutional uses, literally thousands of existing and vacant home sites have been annexed to the City since 1960. Based upon data from the 2000 Census, the area annexed to the City from 1960 to 2006 is the place of residence of 10,085 people. Thus, if the City’s boundary had remained constant from 1960 to 2000, the City’s population would have been 28,341 instead of 38,426. [Boundary Growth Map]