There is a feminist theory of water being female but I can't remember the basics of it .
It should be noted that water imagery is not always symbolic of life. According to The Anatomy of Criticism,“Water . . . traditionally belongs to a realm of existence below human life, the state of chaos or dissolution which follows ordinary death, or the reduction to the inorganic. Hence the soul frequently crosses water [e.g. the rivers Jordan or Styx] or sinks into it at death” (Frye 146). Morton’s goal (and we should heed the mort that is part of his name) is a vast, chaotic ocean; he is seeking limitless salt water, not Sweetwater. The water there does not represent a life-sustaining fluid, but rather the death that Morton (who has “tuberculosis of the bones”) is rushing toward. Although he never makes it to the Pacific, water is present at his demise: “he dies crawling like a snail towards a puddle in the middle of the desert—the urine of his own puffing and wheezing locomotive” (Frayling 260). The crashing waves on the soundtrack underscore the irony of the situation (Morton’s great ambition coming to so little), but also re-emphasizes the association of water and death.So water imagery can have opposite associations, and in OUATITW, when connected to Morton, it signifies death. When water is linked to Jill, however, it represents life.