Clare's bid to reach 5 consecutive Munster U21 Hurling Finals has fallen short.
A dominant second half saw Waterford beat the Banner by 3-23 to 1-11.
A second half tally of 3-13 sent the Deise on their way to a Munster Final.
Clare started the game brightly with an early goal from Feakle's Oisin Donnellan, and they led by 1-4 to 0-2 after 10 minutes.
Waterford fought back strongly led by their senior contingent with Austin Gleeson, the Bennett brothers and Patrick Curran all on the scoreboard.
Clare had 7 different scorers in the opening half, and led by 1-9 to 0-10 at the break having played with the aid of a strong breeze in the opening half.
Waterford made the perfect start to the second half as Stephen Bennett goaled and Shane Bennett pointed twice in the first three attacks to give the Deise a three point lead.
Stephen Bennett pounced for his second goal with Colm Roche also finding the net to leave the Deise 3-19 to 1-10 ahead with 15 minutes left to play and ending the game as a contest.
Waterford controlled the game throughout the second half to run out comfortable winners.
They will now face either Tipperary or Limerick in the decider with those sides meeting in Thurles on Thursday evening.
