In order to support agriculture a rail network was built throughout Otago. Starting in Dunedin in 1889, reaching Hyde by 1894, Clyde in 1907 and Cromwell in 1921. While the gold rush diminished less labour-intensive gold mining became more common. From the 1880s quartz mining (instead of alluvium) became possible, while massive dredges continued to work the old deposits. These dredges also inspired the first hydro electric power station at Bullendale near Queenstown in 1886. This gold boom peaked between 1890–1900 but put a lot of individual prospectors out of business.