Hi
I am totally with Ben and Lizzie on this, Its not only a great safety device and makes life easier, it also makes the water taste good too.
Saying I have drunk the water for years no problem, what does that mean exactly? Most people have never been electrocuted so lets forget RCD's ? Some people do have far better defences against water borne diseases its true, but with drinking water drawn from far and wide I would rather be safe than sorry.
Many people think UK water is totally safe and in general thats true, but the chlorine added only protects the water for a short time, allsorts of nasties can develop in tank water.
This is from the DWI
Water from storage can be safe to drink, providing the cistern:
is not too large, so that standing water is limited (25 litres (5 gallons) per home is the guideline);
is flushed to waste should the water not have been used recently, depending on circumstances such as warmth and number of days unused;
has a lid which excludes light and is tightly fitting and securely fastened, so that birds, vermin, and dirt cannot get in;
has vents, including overflow, that are screened so that insects and particles cannot get in;
is insulated and in a cool place so that, ideally, the temperature does not exceed 20° C;
is cleaned, and disinfected annually as recommended. Cleaning is very important in order to remove even inorganic debris which could provide a habitat for bacteria, including legionella; and
is periodically sampled to ensure that too many bacteria are not present (depending on circumstances, between two and four times a year is normally advised).
However, water quality in storage can deteriorate