Collins Eddy is a cutoff portion of the Sacramento River southwest of Kirkville. It is one of a group of four such lakes; the others are Hiatt Lake (the northernmost, directly north of Collins Eddy), Horseshoe Lake (directly south of Collins Eddy), and Mystic Lake (the southernmost). Hiatt Lake and Mystic Lake are quite shallow and largely dry up each summer, but Collins Eddy and Horseshoe Lake are deeper.