When experts are concerned the water supply might contain contaminants such as illness-causing bacteria, the local government will issue a Boil Water Advisory. The most efficient way to remove these contaminants and kill bacteria is to increase the amount of oxidizers in the water supply, particularly chlorine and chloramines.
So what does a Boil Water Advisory have to do with hair? Quite a lot, actually! The increase in oxidizers creates an effect similar to adding a little bit of bleach with every shampoo -- not enough to lighten hair, but enough to cause serious effects on the health and beauty of the hair. The higher the pH of the water, the more the cuticle will open resulting in a deeper bond between the minerals and hair. Symptoms of mineral buildup include: