6. Conclusions
The following conclusions were obtained from the work presented
in this paper:
The applicability of the water footprint methodology in WWTPs
was demonstrated.
The application to a specific WWTP, which currently treats
4,000 m3
$d1
, resulted in a water footprint of
3.6$106 m3
$month1 for the current operation, with an intensity
of 1.45 m3 required for freshwater$m3 treated wastewater and
2.1$106 m3
$month1 for enhanced phosphorus removal.
The WWTP under study reduced the water footprint by 51.5%
and 72.4% when using secondary treatment and chemical
phosphorus removal, respectively, to fulfill the legal limits,
where blue water footprints of 180,180 and
192,517 m3
$month1
, respectively, were obtained.
Phosphorus removal should be a priority due to its higher
impact after treatment and higher reduction of the water
footprint.
The water footprint illustrates the beneficial role of WWTPs
within the urban water cycle.
Ack