001-40 WC 139 NOV-DEC24 PAPERTURN - Flipbook - Page 11
Instead of grey or green, somewhere in between
This is why yet another prevailing storyline is that grey
(primary) green (secondary) or green-grey wastewater
solutions have the potential to provide huge cost savings
while reducing emissions.
A study conducted by the University of Boulder in partnership with Brigham Young has found that in the U.S. alone, a
transition to more green wastewater treatment solutions has
the potential to save US$15.6 billion and just under 30 million
tonnes of equivalent CO2 emissions over a 40 year period.
In an interview with Science Daily, researcher and first
author of that study Braden Limb observes if “there could
be a switch to nature-based solutions such as constructing
wetlands or reforestation instead of building yet another treatment facility… those options could sequester over 4.2 million
carbon dioxide emissions per year over a 40-year time horizon
WAT E R C A N A D A . N E T
and have other complementary benefits we should be aiming
for, such as cheaper overall costs.”
Yet another study released in 2022 entitled Nature-Based
Solutions Coupled with Advanced Technologies points to similar
benefits of combining grey-green technologies.
The study tellingly points to the fact that “by 2050, 68 per
cent of the global population is projected to be urban… and
water demand is expected to increase between 20 and 30 per
cent due to (a combination of ) population growth, socio-economic development, changes in consumption habits and
higher demand from industrial and domestic sectors.”
In response to that challenge, coupled grey-green/greengrey “have a great potential for facilitating decentralized
treatment schemes in cities by enabling water reclamation or
reuse, enhancing treatment of emerging contaminants and
eliminating toxic products or by-products.”
WATER C AN ADA • NOV EMBER/ DECEMBER 2024
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