There is definitely a difference, says Ouidad
Q: Are certain climates better for the health of your hair? What about certain cities with water quality? (I.e. hard water, versus soft water. What's the difference?)
Ouidad: Climates that are not too dry or not too humid are best for the health of your hair. Hard water is too harsh and strips the life out of hair. Soft water causes build-up on your hair, which leads to long-term dryness and dehydration. I recommend Ouidad Water Works clarifying shampoo which neutralizes the damage that both hard and soft water can cause.