The heating system was built in 1913. In 1982 it was modernized to utilize hot water, rather than steam, to provide heating. In making the upgrade to hot water, Willmar Municipal Utilities achieved higher efficiencies. As part of the 1982 renovation, Willmar Municipal Utilities rebuilt the entire district heating distribution system. Following the renovation the utility experienced small growth in the system, with expansion ending in 1990.  As of June 2017, the City Council approved a resolution to decommission district heat effective July 1, 2020.