watford was created as an urban district under the local government act 1894, and became a municipal borough by grant of a charter in 1922. the borough had 90,301 inhabitants at the time of the 2011 census. the borough is separated from greater london to the south by the urbanised parish of watford rural in the three rivers district. the watford subdivision of the greater london urban area, which includes much of the neighbouring districts, had a total population of 120,960 in the 2001 census.