In terms of base power Hydro Pump is still stronger at base 110 (165 if STAB factored).
Water Pulse is base 60, boosted to base 90 power with the 50% addition from Mega Launcher (Mega Blastoise's ability) (And 135 with STAB Factored). That means it becomes equivalent power to Surf, with an extra confusion chance, but is still weaker than Hydro Pump
