Sulphur Springs, IowaSulphur Springs is an unincorporated community in Buena Vista County, located in the U.S. state of Iowa.HistorySulphur Springs' population was 85 in 1900, and 115 in 1925. The population was 50 in 1940.GeographyThe village is located between Storm Lake and Newell, east of U.S. Route 71. A grain elevator complex owned by a farmers' cooperative is in Sulphur Springs, located on the Canadian National Railway mainline from Chicago to Sioux City, which runs through Sulphur Springs.