Potable water is usually supplied by the local water company to a stop tap in the road adjacent to your building site. They will charge for this connection. It is then your responsibility to run a supply pipe from that stop tap to your building.
If you have a private water supply then other factors should be considered and these is covered in the Drinking Water Inspectorate web site
Filtered drinking water
People are increasingly installing activated carbon drinking water filters to supply chlorine free water in the kitchen. This makes sense as an alternative to buying bottled water not only because of the savings in plastic bottles but also the ‘food miles’ involved with the distribution and delivery. Normally a third tap is fitted to the sink (either a normal tap or a ‘hold down’ type) so that the life of the filter is tied to the drinking water consumed rather than the total cold water going into the sink. The filter is usually housed under the worktop. It may be necessary to reduce the water pressure using a pressure reducer, depending on the rating of the filter housing.