 Pat Fenlon's Derry side had lost their three previous league games |
Peter Hutton's second-half winner helped take some of the pressure off manager Pat Fenlon although the Candystripes were far from convincing. Waterford, who went into the game after four successive defeats, had periods of dominance and Paul McCarthy hit the Derry crossbar in the first half.
Hutton's 75th-minute winner came after an excellent Ruaidhri Higgins cross.
Derry had lost their three previous league games but the win means they are seven points behind leaders St Pat's.
The leaders had to be content with a scoreless draw against their Dublin rivals Bohemians on Friday evening.
Drogheda moved level on points with Pat's after claiming a 3-0 home win over Sligo.