Waterford had the opening three points and they led 0-6 to 0-5 at the interval. But Hayes struck the first goal after 37 minutes and it was 1-8 to 0-9 when Limerick had further goals by Hayes and substitute Luke Cardy to wrap up the win.
David Looby scored seven of Waterford’s points, with Shane O’Meara getting three.
Scorers for Limerick: R Hayes 2-2, L Cardy 1-0, D Corrigan, P Sheehy, A Storan 0-2 each.
Waterford: D Looby 0-7, S O’Meara 0-3, E Kiely, M Sweeney 0-1 each.
LIMERICK: L Moylan; S Murphy, A Ryan, F Murphy; J Wallace, S Irish, N Sheehy; D Donegan, A Kearns; A White, R Hayes, D Kelly; D Corrigan, P Sheehy, A Storan. Sub L Cardy for Hayes.
WATERFORD: K Dwane; D O’Grady, D McGuckian, C O’Dwyer; N O’Mahoney, S O’Reilly, L Cooney; C Prunty, J Elstead; S O’Mara, D looby, D Sheehan; D Kiely, M Phelan, M Sweeney.
Referee: D Marnane, Cork.