Water that is 'alive' is - simply - fresh, clean, organic, and unprocessed - i.e. natural drinking water in its purest form. This may include fresh spring water, bottled spring water, snow and ice, water in fresh fruits (e.g. live coconut water), rain water, morning dew, etc. All forms of the good-ol' H20.
Good quality live water avoids all the contaminants in tap water, e.g. copper and other metals leaching from the pipes, the bacteria and organisms that may be living in the pipes, contaminants that cannot be purified by water purification plants (such as estrogen), as well as added toxins, such as chloride and sometimes fluoride.