Whether you like it or not, we are in the middle of a water
crisis. You can blame it on climate
change or aging infrastructure or green-lawn addicts, but whichever devil you
choose the outcome is still the same: a diminishing supply struggling to meet an
ever-growing demand.
Decentralized water systems (both treatment and delivery) can
attack the problem of a shrinking water supply in two ways. First, advances in water reuse now allow
for pristine, potable-quality water to be discharged back into the water supply,
thereby curtailing the amount of water “lost” to pollution. Secondly, when onsite water treatment is
combined with water reuse, we can insure that valuable drinking water is not
squandered on green lawns in the desert or urban carwashes.
While municipal water treatment and delivery systems are most
often associated with centralized systems (like city sewers or water utilities),
the refinement of treatment technologies, ever-grander land development, and the
push to “green” public and private industry is sure to change all that: one day
onsite water treatment will go beyond the backyard septic system and bleed into
the municipal market where it can reach its full potential and vastly improve
the management and conservation of our water resources.
In Europe, that day has already come…
The public sewer systems in Germany are over 100 years old
and rapidly deteriorating. Experts
warn it could take years and several billion dollars to rehabilitate the
centralized systems currently in place.
The high cost associated with maintaining the existing centralized
systems has prompted the exploration of alternative treatment systems. “As with an old car,” explains Dr.
Harald Hiesll of the Fraunhofer Institute for Systems and Innovation Research
ISI (Fraunhofer-ISI), “if the costs for
repairs and renovations start to increase, you should think about whether to
make further investments in the old system or whether a new system would be more
sensible in the long term"
In April of 2003, the
Fraunhofer-ISI initiated the AKWA 2100 project in order to “investigated
alternative water infrastructure systems.”
The study concluded that although rehabilitating the current
centralized system was the least expensive option, abandoning a centralized
system altogether in favor of a combination of decentralized water treatment and
water reuse was the better option.
According to Dr. Hiessl,
the sustainable aspects of combining onsite water treatment with water
recycling far outweighed the 5-15% increase in cost.
Although this study was conducted in Europe, it has
international implications. The
conclusion drawn by the study – that decentralized systems in an urban
environment are “technologically and economically feasible”– should serve as a
clarion call to municipalities around the world.
There
are several reasons for a municipality to encourage onsite water treatment. A decentralized system allows for
greater flexibility when it comes to growth and development. Onsite water treatment facilities also
allow for the development of previously inaccessible areas, opening up
development opportunities for communities bursting at the seams. Of course, as cities expand, the strain
on water resources increases. What better way to mitigate increased water demand
than to combine water treatment with water recycling?