Sourdough Dam, made completely of logs and earthen banks, was the original Tie Hack Dam before the current engineered reservoir and dam were built. Sourdough Creek, for a century, was a major source of timber production in Johnson County. Timber workers, known as “tie hacks”, would cut logs and stack them within the creek through the winter months. In the spring these earthen dams were blown up, and flumes, sometimes three and a half miles long, carried the heavy ties down Clear Creek to Buffalo. In 1925, two years after the Clear Creek Tie and Timber Company was formed, 15,000 ties were floated down Clear Creek. At the peak of production, just prior to the Great Depression in 1929, that number expanded to roughly 15,000 – 16,000 ties.