Although it is mainly used for tap water now, since it was completed it has been used for hydroelectric power generation (Japan's first commercial hydroelectric power) which contributed to Kyoto's modernization, such as Japan's first operation of electric railcars (Kyoto Electric Railway, which was later bought by Kyoto Municipal Streetcar).
現在は水道用水としての用途が最も多くなっているが、完成当初から水力発電（営業用として日本初）が行われ、その電力を利用した日本初の電車（京都電気鉄道、のち買収されて京都市電）が開業するなど京都の近代化に貢献した。