Among the first projects in 1870 were a stone dam and a wrought iron bridge built on the Big Blue River. A hydroelectric power plant was then added to provide power for manufacturing and for the town. The power plant was destroyed by a flood in 1903. In the late 19th century and early 20th century there were four gypsum mines in the area. The population peaked around 1910 at over 1,750. The public library, built in 1875, is the oldest library west of the Mississippi in continuous operation in the same building.