A system includes a mixing assembly configured to mix a liquid fuel and a water to generate a fuel mixture. The fuel mixture is configured to combust in a combustor of a gas turbine. The mixing assembly includes a liquid fuel passage disposed in an integrated housing. The liquid fuel passage is configured to flow the liquid fuel and to exclude liquid traps. The mixing assembly also includes a water passage disposed in the integrated housing. The water passage is configured to flow the water and to exclude liquid traps. The mixing assembly also includes a mixer disposed in the integrated housing and coupled to the liquid fuel passage and the water passage. The mixer is configured to mix the liquid fuel and the water to form the fuel mixture.