Old Water takes place during a severe drought in southwest Idaho. The year is 1967. Early settlers to the Feather River country have priority or "old water" rights. Rancher, and primary character, Avery Jankcovic has a later or "new" water right that can't be honored due to the shortage. His desperation to save his ranch causes him to do things that his moral code, or the law, doesn't usually allow. It puts him at odds with his wife and daughter who he relies on for help running the ranch as their son has just gone to Vietnam. The family soon finds out, there's no easy fix for an absence of water.