Abstract:
This paper presents the results of a survey on domestic water consumption
inside buildings covering some countries in European and American
continents, namely Portugal, United States of America – USA and Brazil..
Some studies were identified and in which one was found the percentage of
waterconsumed in the various activities carried out within the buildings,
either by simple activities performed by residents, as well by appliances
that add up the heaviest services automatically (dish and clothes
washers).
Considering the residential water profiles it was identified which part
could be supplied by rainwater and the essential part exclusively supplied
with drinking water. From this perspective was performed some calculations
to find out the water savings by using rainwater for domestic purposes and
which appliances inside buildings are eligible to be supplied. As
complementary and considering that waste water generated by some
appliances (showers) it was performed the calculations including the
wastewater reclaimed inside buildings. The study finds out an average of
drinkable water savings of
28 to 100 % for WC cisterns using rainwater and reclaimed water. Some
other savings are presented according to sanitary appliance and inside or
outside house activities when rain and reclaimed water were used. In
conclusion it is noted that for the first part of residential water
consumption there is a range of possibilities to promote the rational use
of water by adopting measures involving design, saving water equipment and
educational campaigns. For the second part it was highlighted the use of
rainwater as an alternative.