Sanitary districts were formed under the terms of the
Public Health Act 1872 (
35 & 36 Vict. c. 79). Instead of creating new bodies, existing authorities were given additional responsibilities. The sanitary districts were created on 10 August 1872, when the act received
royal assent, and the existing authorities were able to exercise their new powers from their first meeting after that date. The powers and responsibilities initially given to sanitary authorities in 1872 were relatively limited. They had to appoint a medical officer, but other powers were generally permissive rather than compulsory. Three years later the
Public Health Act 1875 (
38 & 39 Vict. c. 55) substantially broadened the scope of powers and expectations on sanitary authorities.
Urban sanitary districts were formed in any
municipal borough governed under the
Municipal Corporations Act 1835 (
5 & 6 Will. 4. c. 76), in any
improvement commissioners district formed by an act of Parliament, and in any
local government district formed under the
Public Health Act 1848 (
11 & 12 Vict. c. 63) or
Local Government Act 1858 (
21 & 22 Vict. c. 98). The existing governing body of the town (municipal corporation, improvement commissioners or local board of health) was designated as the
urban sanitary authority. When sanitary districts were formed there were approximately 225 boroughs, 575 local government districts and 50 improvement commissioners districts designated as urban sanitary districts. Over the next nineteen years the number changed: more urban sanitary districts were formed as towns adopted legislation forming local boards and as additional boroughs were incorporated; over the same period numerous urban sanitary districts were absorbed into expanding boroughs.
Rural sanitary districts were formed in all areas without a town government. They followed the boundaries of existing
poor law unions, less the areas of urban sanitary districts. Any subsequent change in the area of the union also changed the sanitary district. At the time of abolition in 1894, there were 572 rural sanitary districts. The
rural sanitary authority consisted of the existing poor law guardians for the rural parishes involved. The
Local Government Act 1894 (
56 & 57 Vict. c. 73) brought an end to sanitary districts in England and Wales. In boroughs, the corporation was already the sanitary authority. All other urban sanitary districts were renamed as
urban districts, governed by an urban district council. Rural sanitary districts were replaced by
rural districts, for the first time with a directly elected council. It was a requirement that whenever possible a rural district should be within a single
administrative county, which led to many districts being split into smaller areas along county lines. A few rural districts with parishes in two or three different counties persisted until the 1930s. The
Local Government Act 1972 made district councils,
London borough councils, the
City of London Corporation, and
Inner Temple and
Middle Temple sanitary authorities. ==Ireland==