Johnsonville was proclaimed a local board in 1874. From 1881 it was a dependent town district, renamed in 1887 the Johnsonville Town District. In 1908 the Town Board became independent. In 1909 John Rod, Chairman of the Town Board, negotiated for electric power; supplied by the Hutt Valley Electric Power Board and installed in Johnsonville by Norman Heath & Co. The board was active in the 1912-1922 period when gas lighting and drainage were installed and streets kerbed and channeled. In 1912 a water reservoir was built for water supplied from Ohariu Valley, and a new reservoir built in 1922. Drainage installed in 1912 was to a septic tank in Ngauranga Gorge. The septic tank lasted to 1953; when Johnsonville amalgamated with the Wellington City Council in April and the council completed a main sewer to the area. Surrounding areas also joined Wellington; like Raroa, which had been in the Hutt County Council.