System for turbine combustor fuel mixing

A system includes a plurality of interconnected mixing assemblies (50) configured to mix a first fuel (42) and water (15) to generate a first mixture (80), and mix a second fuel and the water (15) to generate a second mixture (94). The first and second fuel mixtures (80,94) are configured to combust in a plurality of combustors (16) of a gas turbine (111). The interconnected mixing assemblies (50) include first and second fuel passages (70,80), a water passage (74), first and second mixers (78,92), first and second fuel valves (72,88), and first and second water valves (76,90) disposed in an integrated housing (150). The first fuel valve (72) has a first fuel flow coefficient between approximately 1.0 to 1.5, the second fuel valve (88) has a second fuel flow coefficient between approximately 3.0 to 5.0, the first water valve (70) has a first water flow coefficient between approximately 0.4 to 0.55, and the second water valve (90) has a second water flow coefficient between approximately 3.5 to 5.0.