Water & Wastewater
Scarcity
In 2009 , I wrote : “ We are failing to manage our global water resources . This is not because of a lack of water as such . Rather , it is because rising populations and expanding economies on the one hand and environmental degradation ( much of it due to global warming ) and lack of investment on the other are placing intolerable pressure on water resources .” ( 1 ) Today , 13 years later , I would not change a word . The two interconnected problems remain : water scarcity caused by inefficient handling of the resource and by climate chaos , and inadequate wastewater treatment systems . It is not for lack of initiatives and projects . The problem is that global warming has gotten worse at a faster rate than the steps being taken to tackle the problems . The extreme heat and drought of this summer , followed by the devastating floods in Pakistan , are symptoms of this . After a prolonged drought , the earth is unable to absorb rain , so there are run-offs and flash floods once the rain begins . In poorer countries , wastewater is not being treated properly , and poor sanitation is causing the deaths of 800 children a day ( 2 ) . Unsurprisingly , the worst droughts occur in northern Africa and the Middle East ,
but the situation in Greece and Spain is equally alarming ( see map ). Among industrial countries , the USA , China and India are also major drought regions , which could affect the global economy . Apart from drinking , water is essential to industry , agriculture and power generation . Its absence is felt in countries that rely on water-cooled nuclear reactors to generate electricity .
Remedies
What can be done ? There are at least five overlapping areas where measures are being taken : ( 1 ) recycling ; ( 2 ) savings and economies of both water and power ; ( 3 ) expand and update wastewater treatment ; ( 4 ) improve the quality and quantity of drinking water ; ( 5 ) improve flood management .
1 . Recycling Recycling is a natural process ( rain , runoff , evaporation , cloud formation , rain , etc .) that has been disrupted by climate change . Because of this disruption and population pressures , it has become necessary to create shorter recycling processes and “ closed loops ” wherever possible . The scope for recycling is considerable , as several applications do not require water
Brexit and sewage
The UK ’ s sewage problem has literally raised quite a stink . Beaches and rivers have been polluted to an extent rarely seen in advanced industrial countries . This occurred after the UK government relaxed the rules governing discharge of wastewater into the environment . Companies are now allowed to discharge water that has been only partially treated . The rules were part of the UK ’ s obligations under EU law , which since Brexit no longer apply . The crux of the problem is that certain chemicals required in wastewater treatment are in short supply . One of these is ferric sulphate , an acid that removes phosphorus and prevents the growth of algae . The reason for the shortages is that HGV drivers are increasingly reluctant to drive between the UK and the EU because of the red tape that exists as a consequence of the UK leaving the EU .
of drinking quality . This “ grey ” water can serve for irrigation , e . g ., watering , street cleaning , car washing or industry . But it is possible to go further , treating used water for drinking purposes . This already
Water Stress by Country : 2040 ratio of withdrawals to supply
Low (< 10 %) Low to medium ( 10-20 %) Medium to high ( 20-40 %) High ( 40-80 %) Extremely high (> 80 %)
NOTE : Projections are based on a business-as-usual scenario using SSP2 and RCP8.5 .
For more : ow . ly / RiWop
WORLD RESOURCES INSTITUTE
20 Valve World November 2022 www . valve-world . net