The Canadian Pacific Railway dominated in the transportation industry; its rival, the Great Northern, could not compete. All the Great Northern steamships on the lake were retired by 1910, and the railway between Bonner's Ferry and Kuskanook was closed down by 1915.

The First World War broke out in 1914, and Creston answered the call to arms. The brave men of the 415` Company, Forestry Corps, left the quiet valley they had come to call home to serve overseas. One hundred and seventy-five men boarded the train; twenty-six never returned.

The number of small communities in the valley increased in 1919, when Lister Settlement was established. This was a settlement, founded by Colonel Fred Listen for soldiers returning from the war. Residents bought their land over time, and established a store, church and school within a few years. In 1922, a soldiers' monument was unveiled in the downtown area of Creston, engraved with the names of the Creston soldiers who had died in the war.

The local industries expanded quickly as mechanised equipment was brought in. The first bulldozer in the valley was used by the Canyon City Lumber Company, replacing horses.

Agriculture became a more and more significant element of the region's economy. By the early 1920's, Wynndel had earned the title "Strawberry Capital of the World." Over