Page 9 - Environmental_Ecology

9

Reuse of treated wastewater can provide significant environmental, social and economic benefits.
Moreover, when compared to alternative sources of water supply such as desalination or water transfer,
water reuse often turns out to require lower investment costs and energy, also contributing to reduce
greenhouse gas emissions.

Reuse of treated wastewater can be considered a reliable water supply, quite independent from seasonal
drought and weather variability and able to cover peaks of water demand. This can be very beneficial to
farming activities that can rely on reliable continuity of water supply during the irrigation period,
consequently reducing the risk of crop failure and income losses.

Water reuse contributes to the broader water sector which is a key component of EU eco-industrial
landscape. For this reason water reuse also encompasses significant potential in terms of the creation of
green jobs in the water-related industry, and it is estimated that a 1% increase in the rate of growth of the
water industry in Europe could create up to 20.000 new jobs.

At present, about 1 billion cubic metres of treated urban wastewater is reused annually, which accounts
for approximately 2.4% of the treated urban wastewater effluents and less than 0.5% of annual EU
freshwater withdrawals. But the EU potential is much higher, estimated in the order of 6 billion cubic
metres – six times the current volume. Both southern Member States such as Spain, Italy, Greece, Malta
and Cyprus and northern Member States like Belgium, Germany and the UK already have in place
numerous initiatives regarding water reuse for irrigation, industrial uses and aquifer recharge. Cyprus and
Malta already reuse more than 90% and 60% of their wastewater respectively, while Greece, Italy and
Spain reuse between 5 and 12% of their effluents, clearly indicating a huge potential for further uptake. 1

2.2 Main types of water reuse

A 2017 report by UN-Water notes that water reuse is mainly driven by legislation and water prices. It
distinguishes three main types of water reuse: 1) direct potable reuse, where appropriately treated waste
water is fed into the water supply network; 2) indirect potable reuse, where treated waste water is
released into surface waters and groundwater used as drinking water sources; and 3) reuse for
non-drinking purposes, including agricultural irrigation, industrial use (for instance, as processing or
cooling water), recreational use (for example, for snowmaking or golf course irrigation), environmental use
(for instance, for groundwater recharge or wetlands restoration), and urban use (for example, for irrigation
of public parks, fire protection systems or street cleaning). The report notes that the reuse of water in
agriculture is one of the areas of great potential. A number of opportunities are associated with water
reuse, including: increasing water availability in a sustainable way; delivering energy savings and
reductions in greenhouse gas emissions from water treatment; and contributing to climate change
adaptation.
2

1 Water Reuse - Environment - European Commission https://ec.europa.eu/environment/water/reuse.htm
2 https://www.europarl.europa.eu/RegData/etudes/BRIE/2018/625171/EPRS_BRI%282018%29625171_EN.pdf