Waterford stay third after a last-gasp Gary McCabe penalty secured a 2-2 draw for bottom-side Bray at the Carlisle Grounds.
Gavan Holohan and Courtney Duffus got the goals for Waterford after Daniel McKenna's third-minute opener.
Gavan Holohan headed home the equaliser two minutes before half-time.
Striker Courtney Duffus put the Blues in front on 69 minutes but a stoppage time penalty scored by Gary McCabe following a mistake by defender Dave Webster forced goalkeeper Lawrence Vigouroux to take down Daniel Kelly inside the 18 yards box.
The Blues remain in third position, four points behind the leader's Dundalk and two points behind second placed Cork City. Waterford haven't won a league game at the Bray venue since April 1999.
Dundalk moved two points clear at the top when Stephen Kenny's side came from 1-0 down to win 4-1 at Derry City and inflict a first home defeat of the season upon the Candystripes.
