Place bacon in a large skillet and cook over medium-high heat, turning occasionally, until evenly browned, about 10 minutes. Reserve fat; drain bacon slices on paper towels.
Place garlic in the same skillet; cook over medium heat until golden, about 2 minutes. Add milk, broccoli, garlic powder, salt, and pepper; reduce heat to medium-low. Cook and stir until milk is heated through, 5 to 7 minutes.
Stir water and flour into the milk mixture. Cook, stirring constantly, until sauce is thickened, 5 to 7 minutes. Mix in the cooked bacon.