‘‘Average Waves in Unprotected Waters’’ begins at first light on the day Bet Blevins, the story’s protagonist, is to institutionalize her intellectually disabled son, Arnold. At the age of nine, Arnold has become too difficult for Bet to manage. In the shabby, one-room apartment, Bet wonders, as she prepares Arnold’s things and dresses him one last time, if he understands what is happening and if she is truly making the right decision. As they leave the crumbling apartment building, Mrs. Puckett, a kindly neighbor who is crying, stops Bet and gives her cookies for Arnold, but he runs off without acknowledging the woman who has baby-sat for him since his birth.
After taking a bus from their apartment, Bet and Arnold arrive at the train station. Bet has purchased gum, which she gives to a nervous Arnold. As the train leaves, he becomes calmer and falls asleep. While Arnold sleeps, Bet remembers him as a younger child. She remembers her husband, Avery, who left a few weeks after Arnold’s mental disability was diagnosed. She determines that she and Avery married too young, against her parents’ wishes. She wonders if the gene that caused Arnold’s disability came from Avery or from her. She speculates that it came from her because, ‘‘she never could do anything as well as most people.’’ She wonders why she was so eager to leave her home, which she now sees as ‘‘beautifully free and spacious.’’ She realizes that she has had, and continues to have, one virtue: her steadfastness. She remembers herself as a child, at the shore with her parents, and how she used to stand in the waves and let them pound her. She draws a connection between the waves and her life with Avery, remembering that after Avery left, she even stayed in the old apartment for a while, because she ‘‘took some comfort from enduring.’’ Arnold wakes up and she must entertain him. They both watch the conductor come through the train asking for tickets. Arnold laughs at an old woman whom the conductor is accusing of having no ticket. Bet imagines that she is the one the conductor is scolding.
At Parkinsville, Bet and Arnold find a cab to take them to the Parkinsville State Hospital. Arnold wants to eat a cookie, but Bet refuses to give him one. She is afraid that he will get messy, and she wants the people at the hospital to think highly of him and to see that ‘‘someone cherished him.’’ She is afraid that Arnold will go into one of his rages. To appease him, she breaks off a little piece of cookie and gives it to him to eat. When they arrive at the hospital, she asks the cab driver, repeatedly, if he will stay and wait for her. He promises that he will stay.
Inside the hospital, a nurse gives Bet a tour and shows her where Arnold will sleep. As they look around, Bet tries to tell the nurse how to care for Arnold. The nurse assures Bet that Arnold will be well cared for and informs her that she will be not be able to visit Arnold for six months as he becomes acclimated to his new home. After leaving Arnold with his blanket, Bet says good-bye.
Rushing from the building in tears, Bet climbs into the cab and urges the driver to drive quickly to the train station. She has timed her departure so she will not have to wait very long for a train. When she arrives at the train station, she learns that the train has been delayed by twenty minutes. Bet becomes nearly desperate at this news and wonders how she will endure the interminable wait. Just then, the town’s mayor enters the station and announces that he will be giving a twenty-minute speech. Bet is greatly relieved and believes that they have ‘‘come just for her sake,’’ and that from now on, everything will be like that, ‘‘just something on a stage, for her to sit back and watch.’’