According to a 1926 Brainerd Dispatch Article, this painting was done near Clark Lake. Heald was working on site there in the summer of 1926. However, we can tell that the painting is of a river in the area, based on the waves and the way that Heald paints a current running through the water. The dispatch article regards this as one of the best she has attempted and says that it is on display in D.E. Whitney's store on Front St. in Brainerd.
Brainerd Dispatch. “Mrs. Sarah Heald’s Painting on Display.” December 3, 1926.