IDKFA
I am Become Bilbo Baggins
Isn't the water in the South East generally harder than most other parts of the UK? Not that it makes it unsafe to drink, just surprised to see that area particularly highlighted.
Hard water has it's benefits such as containing minerals like calcium and magnesium. However, there are also arguments for soft water being superior. Personal preference.
Personally, like most things in life, I like it hard.