Ben-Gurion University of the Negev Jacob Blaustein Institutes for ...

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It means that demand at basin i is considered to be equal to consumption at basin i. The
water demand elasticity in relation to prices and quantities is a complex subject that
transcend the scope of this work. This is further discussed in Carraro (2007).
When no data on effective consumption is available, estimations were done according
to the different methodologies further documented in the following sections.
As a general principle whenever the recorded demand (officially documented) diverges
from the estimated one, the largest value among them is taken into account. This is
considered to be a safety measure meant to prevent any demand underestimation.
3.4.1.2 Urban Demand (Uj) per node j
Urban demand (Uj) was derived in two different ways: a) public available data or b)
estimations. Whenever recorded data (from public available sources) diverges from
estimated data, the largest figure among them was selected and used in the model.
Figures of urban water demand have been calculated, according to the following
assumptions derived from "Piano delle Acque in Sicilia" (CDEBTAS, 2007): a) every
municipality with less than 5,000 inhabitants consumes 260 liters per inhabitant per
day; b) this value is augmented progressively according to the dimension of the city,
considering that in bigger cities there is an higher consumption of water per inhabitant.
Table 3 shows the classes of consumption adopted.
Table 3- Litres of water consumption per inhabitant per day in demographic classless (CDEBTAS,
2007)
Demographic class Total stock per day (liters)
100,000 340
The total consumption of water is then calculated by multiplying the number of
inhabitants of every municipality r by the respective total approximated consumption
per day, times 365 days. The number of municipalities r in basin i goes from 1 to s.
u p ∗ q ∗365
r = 1,2,..,s; [m 3 /yr] (7)
r = r r
ur =Estimated urban demand at municipality r, (m 3 /yr);
pr= Population at municipality r;
qr= Consumption per day per inhabitant at municipality r, (m 3 /d);
The sum of the estimated consumption at each municipality r in basin i is the total
estimated urban consumption for the entire basin i.