Reporting by Matt Keane
Dessie Hutchinson gave Waterford the lead after 9 minutes after being played in by Noel Hunt, however the home side equalised just after the half hour mark through Dean Shiels.
The Blues went back in front with the last kick of the half with Bastien Héry the provider for Gavan Holohan.
Waterford had some great chances in the second half, including a saved effort from Noel Hunt, but there was a late scare when an Ally Roy strike rattled the crossbar.
It finished Derry City – 1 Waterford FC – 2
Waterford are ever closer to securing European football next season, and are now four points clear of Shamrock Rovers in third place in the league table.