Limerick edge through to join Galway, Cork and Kilkenny
Champions Kilkenny will play Galway in the League Division 1 semi-final, while All-Ireland champions Cork take on Limerick in the other last-four tie.
Limerick crept through to the last four for the fourth consecutive year and, after needing a play-off last year, squeezed out Waterford by virtue of a superior score difference following their 1-9 to 1-9 draw with the Déise in Ballyagran.
John Tuohy's crew got off to a brilliant start thanks to a Niamh Mulcahy goal in the third minute.
Waterford were level after 22 minutes, thanks largely to one of UL's midweek Ashbourne Cup heroes Beth Carton, who finished the opening period with four points.
Mulcahy hit a late point into the strong wind, though, to give Limerick the lead at half-time by 1-3 to 0-5.
Waterford momentarily had one foot in the semi-final when Kaiesha Tobin found the Limerick net to put her side 1-8 to 1-7 ahead with just seven minutes remaining.
Limerick replied with points from Caoimhe Costelloe and Mulcahy, a '45' that brought her tally to 1-6, and though Waterford drew level as Carton brought her own tally to seven points, they could not find the winner.
Clare's semi-final ambitions ended at Parnells, where they lost to Dublin by 1-12 to 0-10.
Siobhán Kehoe scored five points in the first-half as Dublin moved ahead 0-6 to 0-4 at the break.
A late Róisín Baker goal cemented the honours in the Dubs' favour.
In the other Group 2 game, Kilkenny waltzed to a 2-19 to 0-6 win over Meath in Trim.
Galway got the better of Wexford by 2-16 to 4-8 in the winner-takes-all battle to claim the second semi-final berth from Group 1, after Cork had maintained their perfect record with a 2-11 to 2-9 triumph over Offaly at Faithful Fields.
The hosts put Cork to the pin of their collar, but they will now be preparing for a relegation play-off against Meath.