governorates using Eq. (2):
APPWS = 100 VR / PWD (2)
where APPWS is the annual potential for potable
water savings in each governorate (%), VR is the
annual volume of rainwater that could be harvested
in each governorate (m3/y), and PWD is
the annual potable water demand in each governorate
(m3/y).
The average potable water demand obtained
for the 12 governorates was 141.2 L/d per capita.
It ranged from 68.6 to 393.3 L/d per capita. The
annual volume of rainwater that could be harvested
in each one of the 12 governorates was
calculated through the procedure described
above. Table 5 shows the potential water that
could be harvested in the 12 governorates. A
maximum of 15.5 Mm3/y of rainwater can be
collected from Jordanian roof residential buildings
provided that all surfaces are used and all
rain falling on the surfaces is collected. This is
equivalent to 5.6% of the total domestic water
supply of the year 2005. The potential for water
harvesting varies among the governorates ranges
from 0.023×106 m3 for the Aqaba governorate to
6.45×106 m3 (Table 5). The potential for potable
water savings was estimated for the 12 governorates
and it ranged from 0.27% to 19.7%
(Table 5). The potential for saving in Aqaba is the
lowest among all governorates, which is attributed
to the lowest annual rainfall of 42.7 mm
and the highest demand of 228 L/d per capita.