Hydro power is today one of Sweden’s biggest energy sources, producing just above 40% ofSwedish energy. The foundation of the Swedish hydro power was laid in 1918 where theparliament adopted the new hydro law. The objective of this bachelor thesis is to test ElinorOstroms theory of institutional change by analysing the debate in the Swedish parliament that ledto the new hydro law in 1918.An analysis of the parliament debate showed five main theses in the debates; farmers rights totheir own land, Sweden needs the technical development, foreign domination of naturalresources, impact on existing industries, and the First World War with following consequences.Analysing the different arguments on each of the theses can conclude that the debate leading upto the hydro law of 1918 follows the pattern of Ostroms theory of institutional change.