Barnet Rural Sanitary District

From the Wikipedia article on Friern Barnet

In 1875 Friern Barnet was grouped with neighbouring parishes as part of Barnet Rural Sanitary District. In response to a petition by local ratepayers who wished the area to be removed from the Barnet RSD, the parish adopted the Local Government Act 1858 and formed a local board of health of nine members in 1884. Under the Local Government Act 1894 the local board's area became an urban district. The urban district occupied an area of 1,304 acres (5.28 km2) in 1911 and had a population of 14,924. In 1961 it occupied an area of 1,342 acres (5.43 km2) and the population was 28,813. In 1965 it became part of the London Borough of Barnet.