Prohibition came to Kalamazoo in 1915 and the saloons and breweries closed. Baseball, cycling, Grand Circuit horse racing, and an amusement park at Oakwood Beach entertained the City. New City parks created during this time were Milham, Crane, West Main, Muffley, Sherwood, the Waterworks park and Henderson Park. The United States entered World War I in 1917 and the 126th Infantry from Kalamazoo commanded by Colonel Milham Park Joseph Westnedge took heavy casualties. Col. Westnedge was one of those casualties. His brother Richard preceded him in death in the Spanish American War. The City honored the two brothers by renaming West Street Westnedge Avenue and renaming the old cemetery on West Street Joseph B. Westnedge Park in 1920.
Many reforms were sweeping the nation after the turn of the century: prohibition, women's suffrage, recreation for the masses, hygiene, and new types of local government. Kalamazoo set up a Charter Commission in 1917 led by pharmaceutical innovator Dr. William E. Upjohn. The proposed charter followed the Dayton (Ohio) Plan which called for a City Manager-Commission form of government. The new charter passed and a new City Commission was elected on April 1, 1918. For a few years afterward, the City's politics convulsed over the new government. Opponents' attempts to overturn the new charter succeeded, then failed at replacing it. Finally, the City accepted the Manager-Commission and it remains the City's form of government today.
In the same postwar period, Spanish Influenza or Swine Flu decimated populations all over the world. Kalamazoo 'fared better than most' according to the City Health Officer. From September 1918 to April 1919, 4,064 cases of influenza were reported including 125 deaths. The national death rate from the flu was 4 per 1,000 population. Kalamazoo's rate was 2.5 per 1,000. On October 17, 1918 the City Commission, by resolution, prohibited public gatherings, specifically at churches, theaters, movies, pool rooms, dance halls etc. The quarantining of flu patients was instituted by the Board of Health on December 9, 1918. On December 17, public gatherings were again allowed as the number of new influenza cases declined.
The roaring twenties also roared in Kalamazoo. Buoyed by a burgeoning economy, the City's pay-as-you-go plan resulted in a new City Hall in 1931, financed without bonded indebtedness or increase in property tax. Kalamazoo's first municipal golf course, Gateway, was developed in 1924 south of Michigan Avenue where WMU now stands. The flapper lifestyle doomed one Kalamazoo industry, however, the corset manufacturers. Celery was now sharing the fields with pansy cultivation and the fresh flower industry took off. Checker Cab became the only lasting Kalamazoo automobile manufacturer. Michigan's first municipal airport, Lindbergh Field, was the precursor of the Kalamazoo-Battle Creek International Airport.