The Water Is Wide presents a diverse cast of characters, with Pat Conroy as the central figure who tells this autobiographical story in the first person. Conroy doesn't shy away from the autobiographical elements, even naming the protagonist after himself. Pat is the only fully developed character in the novel, evolving as he experiences the secluded island culture and slowly realizes that idealism often clashes with reality. He starts the story as a Southern teacher eager to educate the black children of Yamacraw Island, part of Beaufort, South Carolina's school district, as a way to confront the prejudices he grew up with. Set in the early 1970s, Pat embodies the more liberal, antiwar, and pro-human rights sentiments of the era. However, his passion for helping the children is overshadowed by the school board's eagerness to dismiss him after a year of his unconventional teaching methods with the island children. After discovering the children's illiteracy despite years of education from the white system,

Pat chooses to teach them subjects that better connect with their own world and the world beyond their island. His methods shock another teacher who witnesses him using profanity, calling students "punks," and allowing them to sing and dance in class. Pat's primary adversary is Ezra Bennington, the elderly deputy school superintendent. The narrator describes him as, "Ezra looked, talked, and acted like a huge southern cliché, a parody who was unaware that his type had been catalogued and identified over and over again." Bennington grows to despise Pat's innovative educational approach on Yamacraw.

The school superintendent, Dr. Henry Piedmont, initially supports Pat, seeing a reflection of his own enthusiasm and desire to help others. However, Piedmont's support wanes, not primarily due to racism, but because Pat disrupts the established routine of the teachers under Piedmont's authority. During a later hearing about Pat's potential dismissal, a judge questions Piedmont, asking, "what other punishment could you have levied against this young man besides firing him?" To which Piedmont responds, "We have no other punishment . . . our teachers obey all the rules. We never have to discipline them."

Mrs. Brown is a long-time teacher at Yamacraw, embodying those educators who never require discipline. Pat sees her as the most tragic figure in his life. She follows the orders of the white establishment, thereby betraying her own race. When Pat begins teaching, she exudes self-importance and tells him, "you're overseas now," implying he must adopt new teaching methods. Her approach includes frequent corporal punishment for misbehaving students. She disapproves of Pat's use of music and art in the classroom, insisting that their primary goal is to cover the textbooks provided by the school board. Pat finds this stance ironic because many students in his junior high class struggle to read or write their own names. In his assessment of what he calls "the masque on Yamacraw," Pat notes that Mrs. Brown "was a woman trapped by her own insecurity. She desperately wanted acceptance from whites. She basked in the praise given to her by Ezra Bennington and learned to resent me because I didn't share her views on the island's people."

Each student in Pat's class has a unique personality. Mary, the oldest, serves as an interpreter for the dialect that initially confuses Pat. Top Cat is the class entertainer, performing James Brown songs on demand. Prophet is the class clown, while twins Sidney and Samuel are underachievers even within their already struggling peer group. Through their lively dialogue, readers gain insight into their secluded and predictable lives. They amusingly refer to Beethoven's Fifth as "Bay Cloven the Fifth,"...