CIB W116—Smart and Sustainable Built Environments - Test Input

The activities made for the development of the water agenda were: estimate of the degree of scarcity
of local water, identification of the water consumption indicators reference (IC), definition of actions
and respective impacts of the reduction of the consumption of water.
The estimate of the degree of scarcity was elaborated considering the data made available from ANA
(2007) to the 12 Brazilian hydrographical regions defined by resolution 32 from the National Council
of Hydro Resource – CNRH (2003). It should be noted that this data reflects an initial water
availability of above the actual available level, due to restrictions imposed on the water resources by
its different uses, such as: commitment to the quality of water, flow rates to dilution of effluents,
operation of reservoirs and maintenance of minimum flow rates that was not taken into account in the
water availability. The aforementioned document also presents data relative to the precipitation in the
country, which annual average is 1797 mm, varying from less than 800 mm in semi-arid regions in the
Northeast, to more than 2500 mm in the Amazon.
The impacts of the expected reduction were estimated based on the experience of the authors of this
article in water conservation programs, and also the available bibliography. The definition of the
action plans, in turn, was made taking the average distribution of consumption in dwellings into
consideration.
3. The Brazilian agenda for sustainable dwellings: criteria for
water conservation
The United Nations has utilized as an indicator for water availability per inhabitant, in major regions,
the ratio between the average annual flow rate and the population in a region. On the basis of this
indicator, Brazil is considered rich in water resources, with an availability of 33000 m 3 /inhab.year. It
must be observed, however, that a significant variety in this indicator can be found in the 12 Brazilian
hydrographical regions, with instances of low availability associated with elevated population
concentration, as is the case in the city of São Paulo, which has less than 500 m 3 /inhab/year -
representing a scenario of water scarcity.
The ratio of demand to supply of water resources can be classified in: Excellent (less than 5%);
comfortable (5 to 10%); worrying (10 to 20%); critical (20 to 40%) and very critical (above 40%)
ANA (2007). This value displays a comfortable situation in only some regions of the country.
However, some regions present a very critical ratio of demand to supply. Hence, the proposed water
agenda in a specific region or community should be elaborated as a function of the ratio of demand to
supply of water as the classification presented in ANA (2007). Its structure should incorporate the
following aspects:
• Water consumption indicator (IC) – reference value used to establish target and actions to be
implemented in the building, (L/person.day).
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