Yelm Ditch is an abandoned irrigation canal near Yelm in Thurston County, Washington. It was completed by the Yelm Irrigation Company at a cost of $100,000 on June 29, 1916. At the time, Yelm had a population of a few hundred, and the Yelm Irrigation Project was "one of Western Washington's first irrigation districts", bringing water from the Nisqually River to irrigate farms on the Yelm Prairie. The crops irrigated by the canal included red and black raspberries and Bluelake beans.