The rapidly-growing bottled water industry can undermine progress towards a key sustainable development goal: safe water for all, says a new United Nations report.  

Based on an analysis of literature and data from 109 countries, the report says that in just five decades bottled water has developed into “a major and essentially standalone economic sector,” experiencing 73% growth from 2010 to 2020. And sales are expected to almost double by 2030, from US$ 270 billion to $500 billion.

Released a few days prior to World Water Day (March 22), the report by UN University’s Canadian-based Institute for Water, Environment and Health concludes that the unrestricted expansion of the bottled water industry “is not aligned strategically with the goal of providing universal access to drinking water or at least slows global progress in this regard, distracting development efforts and redirecting attention to a less reliable and less affordable option for many, while remaining highly profitable for producers.”

Says Kaveh Madani, UNU-INWEH’s new Director: “The rise in bottled water consumption reflects decades of limited progress in and many failures of public water supply systems.”

When the Sustainable Development Goals were agreed in 2015, he notes, experts elsewhere estimated an annual investment of US$ 114 billion was needed from 2015 to 2030 to achieve a key target: universal safe drinking water. 

The report says providing safe water to the roughly 2 billion people without it woulds require an annual investment of less than half the US$ 270 billion now spent every year on bottled water.

“This points to a global case of extreme social injustice, whereby billions of people worldwide do not have access to reliable water services while others enjoy water luxury.”

Tap water perceptions

The study quotes surveys showing bottled water is often perceived in the Global North as a healthier and tastier product than tap water – more a luxury good than a necessity. In the Global South, sales are driven by the lack or absence of reliable public water supplies and water delivery infrastructure limitations due to rapid urbanization.

In mid- and low-income countries, bottled water consumption is linked to poor tap water quality and often unreliable public water supply systems – problems often caused by corruption and chronic underinvestment in piped water infrastructure.

Beverage corporations are adept at marketing bottled water as a safe alternative to tap water by drawing attention to isolated public water system failures, says UNU-INWEH researcher and lead author Zeineb Bouhlel, adding that “even if in certain countries piped water is or can be of good quality, restoring public trust in tap water is likely to require substantial marketing and advocacy efforts.”

Not necessarily safe

Dr. Bouhlel notes that the source of bottled water (municipal system, surface, etc.) the treatment processes used (e.g. chlorination, ultraviolet disinfection, ozonation, reverse osmosis), the storage conditions (duration, light exposure, temperature), and packaging (plastic, glass), can all potentially alter water quality. This may be inorganic (e.g. heavy metals, pH, turbidity etc.), organic (benzene, pesticides, microplastics, etc.) and microbiological (pathogenic bacteria, viruses, fungus and parasitic protozoa).

According to the report, “the mineral composition of bottled water can vary significantly between different brands, within the same brand in different countries, and even between different bottles of the same batch.”

The report lists examples from over 40 countries in every world region of contamination of hundreds of bottled water brands and all bottled water types.

“This review constitutes strong evidence against the misleading perception that bottled water is an unquestionably safe drinking water source,” says Dr. Bouhlel.

Water bottlers generally face less scrutiny than public water utilities

Co-author Vladimir Smakhtin, past Director of UNU-INWEH, underscores the report’s finding that “bottled water is generally not nearly as well-regulated and is tested less frequently and for fewer parameters. Strict water quality standards for tap water are rarely applied to bottled water, and even if such analyses are carried out, the results seldom make it to the public domain.”

Bottled water producers, he says, have largely avoided the scrutiny governments impose on public water utilities, and amid the market’s rapid growth, it is “probably more important than ever to strengthen legislation that regulates the industry overall, and its water quality standards in particular.”

With respect to the industry’s environmental impacts, the report says there is “little data available on water volumes extracted,” largely due to the lack of transparency and legal foundation that would have forced bottling companies to disclose that information publicly and assess the environmental consequences.”

“Local impacts on water resources may be significant,” the report says. 

In the USA, for example, Nestlé Waters extracts 3 million litres a day from Florida Springs; in France, Danone extracts up to 10 million litres a day from Evian-les-Bains in the French Alps; and in China, the Hangzhou Wahaha Group extracts up to 12 million litres daily from Changbai Mountains springs. 

Regarding plastic pollution, the researchers cite estimates that the industry produced around 600 billion plastic bottles and containers in 2021, which converts to some 25 million tonnes of PET waste – most of it not recycled and destined for landfills – a mass of plastic equal to the weight of 625,000 40-ton trucks, enough to form a bumper-to-bumper line from New York to Bangkok.

According to the report, the bottled water sector used 35% of the PET bottles produced globally in 2019; 85% wind up in landfills or unregulated waste.

By the numbers 

Among the report’s many insights, derived from data analysis and other information assembled from global studies and literature:

• Over 1 million bottles of water are sold worldwide every minute
• Annual spending per capita worldwide is US$ 34
• Worldwide annual consumption of the three main bottled water types – treated, mineral, and natural – is estimated at 350 billion litres
• The estimated US $1.225 trillion in bottled water revenues represent 17 to 24% of the global market for non-alcoholic packaged beverages
• The biggest market segment (with 47% of global sales) is treated bottled water, which could originate from public water systems or surface water, and that undergoes a disinfection treatment such as chlorination
• Citizens of Asia-Pacific are the biggest bottled water consumers, followed by North Americans and Europeans 
• 60% of global sales are in the “Global South” (Asia-Pacific, Africa, Latin America and the Caribbean)
• By country, the USA is the largest market, with around US$ 64 billion in sales, followed by China (almost US$ 45 billion) and Indonesia (US$ 22 billion). Together, these three countries constitute almost half of the world market. Other top countries by sales: Canada, Australia, Singapore, Germany, Thailand, Mexico, Thailand, Italy, Japan
• The average cost of a bottle of water in North America and Europe is around US$ 2.50, more than double the price in Asia, Africa and LAC ($0.80, $0.90 and $1, respectively). Australia, the fifth largest market, has the highest average price: $3.57 per unit.
• Bottled water per litre can cost 150 to 1,000 times more than the price a municipality charges for tap water.
• Biggest per capita consumers: Singapore and Australia. Citizens of Singapore spent $1,348 per capita on bottled water in 2021, Australians $386
• According to previous studies, about 31% of Canadians, 38% of Americans, and 60% of Italians use bottled water as their primary drinking source. In the Dominican Republic, 60% of households use bottled water as their primary water source, with a strong correlation between income and bottled water consumption. About 80% of Mexicans use bottled water, and 10% use home-purified water as their primary drinking water source; roughly 90% cite health concerns for doing so
• Egypt is the fastest-growing market for treated bottled water (40% per year). Seven other countries from the Global South are among the top 10 fastest-growing markets: Algeria, Brazil, Indonesia, United Arab Emirates, India, Morocco, and Saudi Arabia.
• In Europe, Germany is the biggest bottled water market; in Latin America and the Caribbean, Mexico is the biggest market; in Africa, it’s South Africa.
• Treated water appears to be the market’s largest component by volume, while natural waters appear to generate the most profit.
• Five companies – PepsiCo, Coca-Cola, Nestlé S.A., Danone S.A, and Primo Corporation have combined sales of $65 billion, over 25% of the global total
• Earlier studies of water withdrawals declared in India, Pakistan, Mexico and Nepal showed total estimated withdrawals by Coca-Cola and Nestlé in 2021 at 300 and 100 billion litres, respectively

* * * * * 

UNU-INWEH

http://bit.ly/1vjfKAS

The UNU Institute for Water, Environment and Health is a member of the United Nations University family of organizations. It is the UN Think Tank on Water created by the UNU Governing Council in 1996. Its mission is to help resolve pressing water challenges of concern to the UN, its Member States and their people, through knowledge- based synthesis of existing bodies of scientific discovery; cutting edge targeted research that identifies emerging policy issues; application of on-the-ground scalable solutions based on credible research; and relevant and targeted public outreach.  UNU-INWEH is hosted by the Government of Canada and McMaster University.

******

News release in full, click here

CNN, United States (134,312,034) The plastic water bottle industry is booming. Here’s why that’s a huge problem  https://www.cnn.com/2023/03/16/world/plastic-water-bottles-un-report-climate

Reuters, via Daily Mail, United Kingdom (76,772,682) Rising bottled water consumption signals safe drinking water goal is under threat, says U.N. think tank https://www.dailymail.co.uk/wires/reuters/article-11868165/Rising-bottled-water-consumption-signals-safe-drinking-water-goal-threat-says-U-N-think-thank.html

Agence France Presse, France, a) French, via La Croix, France (2,705,128) La moitié des ventes d’eau en bouteille suffirait à fournir de l’eau potable à tous, selon l’ONU https://www.la-croix.com/environnement/moitie-ventes-deau-bouteille-suffirait-fournir-leau-potable-tous-selon-lONU-2023-03-16-1201259394

b) English via Radio France International (6,120,000) Half of bottled water sales would be enough to give universal access to drinking water (UN)
https://www.rfi.fr/es/m%C3%A1s-noticias/20230316-mitad-de-ventas-de-agua-embotellada-alcanzar%C3%ADa-para-dar-acceso-universal-al-agua-potable-onu

c) Spanish, via La Nación, Argentina (21,474,486)
Mitad de ventas de agua embotellada alcanzaría para dar acceso universal al agua potable (ONU) https://www.lanacion.com.ar/agencias/mitad-de-ventas-de-agua-embotellada-alcanzaria-para-dar-acceso-universal-al-agua-potable-onu-nid16032023/

Bloomberg, United States (30,080,279) Bottled Water Sales Exceed Cost of Providing Safe Water for All, UN Says  https://www.bloomberg.com/news/articles/2023-03-16/bottled-water-boom-detracts-from-safe-drinking-water-focus-un-warns

Agencia EFE, via MSN.com, United States (185,235,630) Hay millones de personas sin agua potable. La ONU acusa a las embotelladoras  https://www.msn.com/es-us/noticias/others/hay-millones-de-personas-sin-agua-potable-la-onu-acusa-a-las-embotelladoras/ar-AA18IbbX

Australian Associated Press, Australia, via Daily Mail, United Kingdom (76,772,682) a) Unquenched Aussie thirst for world’s most costly water https://www.dailymail.co.uk/wires/aap/article-11868183/Unquenched-Aussie-thirst-worlds-costly-water.html
b) Australians are thirsty for pricey bottled water: UN https://www.dailymail.co.uk/wires/aap/article-11868181/Australians-thirsty-pricey-bottled-water-UN.html

Belga, Belgium, from AFP, via Sudinfo (3,804,253)
La moitié des ventes d’eau en bouteille suffirait à fournir de l’eau potable à tous, affirme l’ONU https://www.sudinfo.be/id634776/article/2023-03-16/la-moitie-des-ventes-deau-en-bouteille-suffirait-fournir-de-leau-potable-tous

Algemeen Nederlands Persbureau (ANP), Netherlands, via Noordhollands Dagblad, (1,036,049)  Instituut: fleswater zit ontwikkeling leidingwater in de weg  https://www.noordhollandsdagblad.nl/cnt/dmf20230316_54723590

News sites, original stories (different reporters)

La Nación, Argentina (21,474,486)
Aumento de consumo de agua embotellada hace peligrar objetivo de agua potable de onu: expertos https://www.lanacion.com.ar/agencias/aumento-de-consumo-de-agua-embotellada-hace-peligrar-objetivo-de-agua-potable-de-onu-expertos-nid16032023/

El Español, Spain (33,831,415) El negocio del agua o cómo el ‘boom’ de la embotellada disfraza el fracaso de proveerla de forma segura https://www.elespanol.com/enclave-ods/historias/20230316/negocio-embotellada-disfraza-fracaso-proveerla-forma-segura/748925300_0.html

El Confidencial, Spain (28,465,479)
El desastre global del agua embotellada: más cara y contaminante (y no es más saludable) https://www.elconfidencial.com/tecnologia/ciencia/2023-03-16/desastre-agua-embotellada-cara-saludable_3593902/

L’Obs, France (5,784,242) L’eau en bouteille est-elle un obstacle au développement durable?  https://www.nouvelobs.com/sciences/20230316.OBS70921/l-eau-en-bouteille-est-elle-un-obstacle-au-developpement-durable.html

Les Echos, France (5,297,982) La charge des Nations Unies contre l’eau vendue en bouteille https://www.lesechos.fr/monde/enjeux-internationaux/la-charge-des-nations-unies-contre-leau-vendue-en-bouteille-1916470

Público, Portugal (2,865,936)
Água engarrafada não é mais segura que a da torneira, diz relatório da ONU https://www.publico.pt/2023/03/16/azul/noticia/agua-engarrafada-nao-segura-torneira-relatorio-onu-2042389

Investing, Spain (2,221,188)

Aumento de consumo de agua embotellada hace peligrar objetivo de agua potable de ONU: expertos https://es.investing.com/news/commodities-news/aumento-de-consumo-de-agua-embotellada-hace-peligrar-objetivo-de-agua-potable-de-onu-expertos-2372980

MeteoWeb, Italy (1,340,114)

Uno studio svela il lato oscuro dell’industria dell’acqua in bottiglia  https://www.meteoweb.eu/2023/03/acqua-potabile-acqua-imbottigliata-industria-ambiente-inquinamento/1001215591/

The New Daily, Australia (1,017,563) ‘One of the biggest scams’: Study uncovers the downsides of bottled water fad  https://thenewdaily.com.au/life/health/2023/03/17/bottled-water-environmental-toll/

ABC National Radio, Australia

Full coverage summary, click here

Trapped sediment has robbed roughly 50,000 large dams worldwide of an estimated 13% to 19% of their combined original storage capacity, and total losses will reach 23% to 28% by 2050, UN research warns.

The global loss from original dam capacity foreseen by mid-century – from ~6,300 billion to ~4,650 billion m3 in 2050, a difference of ~1,650 billion m3 – roughly equals the annual water use of India, China, Indonesia, France and Canada combined.

UN University’s Canadian-based Institute for Water, Environment and Health applied previously-determined storage loss rates in various areas worldwide to large dams in 150 countries to forecast cumulative reservoir storage losses by country, region, and globally. 

The United Kingdom, Panama, Ireland, Japan and Seychelles will experience the highest water storage losses by 2050 – between 35% and 50% of their original capacities – the study shows. By contrast, Bhutan, Cambodia, Ethiopia, Guinea, and Niger will be the five least affected countries, losing less than 15% by mid-century.

“The decrease in available storage by 2050 in all countries and regions will challenge many aspects of national economies, including irrigation, power generation, and water supply,” says Dr. Duminda Perera, who co-authored the study with UNU-INWEH Director Vladimir Smakhtin and Spencer Williams of McGill University in Montreal. It is published by the journal Sustainability.

“The new dams under construction or planned will not offset storage losses to sedimentation. This paper sounds an alarm on a creeping global water challenge with potentially significant development implications.”

The researchers applied previously-established storage loss rates worldwide to a subset of nearly 60,000 dams in a database maintained by the International Commission on Large Dams (ICOLD). The subset comprises 47,403 large dams for which original storage capacity and year of construction are known: 28,045 in Asia-Pacific, 2,349 in Africa, 6,651 in Europe, and 10,358 in North, Central and South America.

Large dams and reservoirs – defined as higher than 15 m, or between 5 and 15 m high impounding over 3 million m3 – are essential in many places for hydroelectricity, flood control, irrigation, and drinking water.

River sediment accumulates behind a dam’s barrier. The problem, often ignored, has now become a significant challenge to global water storage infrastructure that must be addressed with a long-term sediment management strategy.

“Sedimentation is a serious issue that endangers the sustainability of future water supplies for many,” says Dr. Smakhtin.

“It stimulates downstream flooding causing erosion, impacting wildlife habitats and coastal populations. And abrasive sediments can damage hydroelectric turbines and other dam components and mechanisms, decreasing their efficiency and increasing maintenance costs.”

Global average annual storage losses amount to approximately 0.36% of initial capacity, the UNU-INWEH study says, noting that figure may err on the conservative side. Previous attempts to estimate a global annual rate of loss from initial reservoir capacity generally agree on a range between 0.5% and 1%. 

Many other studies suggest, however, that reservoir sedimentation rates and associated storage losses are site-specific and vary significantly between regions.

For example, other researchers have estimated the loss from 190 California reservoirs at more than 50% from their original capacities, with 120 reservoirs having lost over 75%. A similar study predicted Japan’s Sakuma reservoir will lose around 44% of its initial capacity by 2040. 

* * * * *

The Americas

The Americas’ 19 countries contain 10,358 large dams with an initial storage capacity of 2,810 billion m3 foreseen falling 28% to 2,014 billion m3 by 2050. And Panama’s 21 dams appear to be facing the highest storage loss: 38%, from an initial 9.5 billion m3 to 5.9 billion m3 by 2050.

Brazil, second after the USA in the Americas in number of large dams, will lose an estimated 23% of its initial storage of 600 billion m3 by 2050.

* * * * *

Europe

Europe’s 6,651 large dams across 42 countries had a total initial storage capacity of 895 billion m3.  The region has already lost 19% of that volume, will lose up to 21% by 2030 and 28% by 2050, the study found.

Among the 42 countries, 33 (~78%) will likely lose over 25% of initial storage by 2050 in part because of the dams’ age. Ireland can anticipate the greatest loss of storage by 2050 (39%), Denmark the least loss (20%). Turkey, Iceland, Hungary, and Cyprus appear to be Europe’s other least-impacted countries.

* * * * *

Africa

Already, the 2,349 dams across Africa’s 44 countries have lost about 702 billion m3 or 15% of their original storage capacity. By 2030 and 2050, cumulative storage losses are estimated at 17% and 24%, respectively.

The Seychelles’ two dams have to date lost about 30% of their original 1 million m3 capacity and are projected to lose 50% by 2050 – the greatest loss of any country. Madagascar, DR Congo, Chad, and Zambia are projected to lose 30% by 2050, while another 11 countries will lose an estimated 25% to 30% by mid-century. 

The lowest storage loss by 2050 is estimated for Niger (11%).  Losses of less than 15% are foreseen for Sierra Leone, Congo, Ethiopia, and Guinea, mostly attributable to their relatively young dams.

A previous study noted that the Aswan Dam on the Nile River, with 99% of estimated trapping efficiency, has almost completely blocked sediment flow to the Nile River Delta. 

The new UNU-INWEH study estimates Aswan dam storage losses at 18%, 21%, and 28% in 2022, 2030, and 2050 respectively.

* * * * *

Asia-Pacific

Combined with those in Australia, and New Zealand, Asia’s 43 countries are home to 35,252 large dams, making it the world’s most heavily dammed region. The region is home to 60% of the world’s population and water storage is crucial for sustaining water and food security. 

In 2022, the region is estimated to have lost 13% of its initial dam storage capacity. It will have lost nearly a quarter (23%) of initial storage capacity by mid-century. 

The loss of storage capacity of Japan’s 3,052 dams (average age: over 100 years) is the most acute in the region.  Having already lost 39% of their total initial storage capacity, they will have lost nearly 50% by 2050 on average, and 67% in some cases.

In 2015, India’s Central Water Commission reported that among 141 large reservoirs over 50 years old, one-quarter had already lost at least 30% of their initial storage capacity. UNU-INWEH estimates that India’s 3,700 large dams will have lost on average 26% of their initial total storage by 2050.

China, meanwhile, the world’s most heavily dammed nation, has lost about 10% of its storage and will lose a further 10% by 2050.

* * * * *

Authors of the new paper note that their rough estimates could be greatly improved through consistent basin-wide monitoring of sediment transport and frequent bathymetry surveys of individual reservoirs.

Dredging can be costly, they add, and only temporary. Sediment flushing is more financially attractive but may have significant adverse impacts downstream. 

Solutions such as bypass (or diversion) are gaining traction due to the growing public quest to minimize dams’ adverse environmental impacts. Bypassing is a technique that diverts the flow downstream via a separate channel to manage high-flow events during which sediment concentration is particularly high.

At their optimum operational levels, bypass tunnels can reduce sedimentation by 80%–90% as mentioned in a previous study. 

Enhancement of the dam height is another alternative to recover the storage loss due to sedimentation. However, this should be executed only after a careful assessment of the dam’s structural strength. 

Such an increase in height will also expand the reservoir area, potentially displacing communities and many species’ habitat. 

Complete dam removal, including those filled with sediments, is a slowly emerging practice, returning rivers to their natural state and reestablishing natural river sediment transport. Treatment and disposal of accumulated sediments may be needed as they may contain heavy metals and other toxins.

“Clearly, this study’s results need to be interpreted by local authorities with consideration given to local specifics and factors,” says Dr. Perera.

“What is most important to underline is the disturbing overall magnitude of water storage losses due to sedimentation.  This adds to the list of world water development issues we need to address with resolve.”

* * * * * 

UNU-INWEH (http://bit.ly/1vjfKAS)

The UNU Institute for Water, Environment and Health is a member of the United Nations University family of organizations. It is the UN Think Tank on Water created by the UNU Governing Council in 1996.

Its mission is to help resolve pressing water challenges of concern to the UN, its Member States and their people, through knowledge- based synthesis of existing bodies of scientific discovery; cutting edge targeted research that identifies emerging policy issues; application of on-the-ground scalable solutions based on credible research; and relevant and targeted public outreach. 

UNU-INWEH is hosted by the Government of Canada and McMaster University, Hamilton, Ontario.

Coverage highlights;

Newswires

Reuters, UK “World’s dams to lose a quarter of storage capacity by 2050 – UN research World’s dams to lose a quarter of storage capacity by 2050 – UN research” https://www.dailymail.co.uk/wires/reuters/article-11624173/Worlds-dams-lose-quarter-storage-capacity-2050–UN-research.html

Agence France Presse, “Trapped sediment in dams ‘endangers’ water supplies: UN” https://news.yahoo.com/trapped-sediment-dams-endangers-water-193052837.html

Agencia EFE, Spain “ONU advierte de amenaza oculta que afecta a los embalses en todo el mundo” (UN warns of hidden threat that affects reservoirs worldwide) https://www.infobae.com/america/agencias/2023/01/11/onu-advierte-de-amenaza-oculta-que-afecta-a-los-embalses-en-todo-el-mundo/

Deutsche Presse Agentur, Germany “Sedimente lassen Speicherkapazität von Staudämmen sinken” (Sediments let the storage capacity of dams decrease) https://www.welt.de/newsticker/dpa_nt/infoline_nt/wissenschaft_nt/article243160207/Sedimente-lassen-Speicherkapazitaet-von-Staudaemmen-sinken.html

SAPO, Portugal “Maiores barragens do mundo podem perder 26% da capacidade de armazenamento até 2050” (Largest dams in the world can lose 26% of the storage capacity by 2050) https://greensavers.sapo.pt/maiores-barragens-do-mundo-podem-perder-26-da-capacidade-de-armazenamento-ate-2050/

Press Trust of India, “3,700 dams in India will lose 26% storage capacity due to sedimentation by 2050: UN study” https://www.moneycontrol.com/news/india/3700-dams-in-india-will-lose-26-storage-capacity-due-to-sedimentation-by-2050-un-study-9835031.html

Ars Technica, United States “Sedimentation threatens to steal capacity from nearly 50,000 dams” https://arstechnica.com/science/2023/01/sedimentation-threatens-to-steal-capacity-from-nearly-50000-dams/

Berita Harian, Malaysia “Empangan seluruh dunia hilang 25 peratus simpanan menjelang 2050” (Worldwide dams lost 25 percent savings by 2050) https://origin.bharian.com.my/dunia/asia/2023/01/1050865/empangan-seluruh-dunia-hilang-25-peratus-simpanan-menjelang-2050

Dawn, Pakistan “Sediment robbing dams of storage capacity Sediment robbing dams of storage capacity” https://www.dawn.com/news/1731221/sediment-robbing-dams-of-storage-capacity

Kompas, Indonesia “PBB: Bendungan Besar Dunia Bisa Kehilangan Seperempat Kapasitasnya pada 2050” (UN: The world’s large dam can lose a quarter of its capacity in 2050) https://www.kompas.com/global/read/2023/01/12/143000170/pbb–bendungan-besar-dunia-bisa-kehilangan-seperempat-kapasitasnya-pada

Le Temps, Switzerland “La capacité de stockage des lacs de barrage se réduit dangereusement” (The storage capacity of dam lakes is dangerously reduced) https://www.letemps.ch/sciences/capacite-stockage-lacs-barrage-se-reduit-dangereusement

Naver, Korea “잦은 가뭄·홍수에 댐 바닥 침전물까지…전세계 물 부족 경고” (Frequent droughts and floods to dam floor sediment… Water shortage warning around the world) https://n.news.naver.com/article/028/0002623070

Coverage summary in full, click here

News release in full, click here

Tapping a fraction can help meet fast-growing global freshwater needs

UN and partner water experts say it is time to increase the tapping of Earth’s diverse and abundant unconventional water sources – the millions of cubic kilometres of water in deep land-based and seabed aquifers, in fog and icebergs, in the ballast holds of thousands of ships, and elsewhere. 

A new book, Unconventional Water Resources, published by Springer and compiled by experts at UN University’s Institute for Water, Environment and Health (UNU-INWEH), the UNU Institute for Integrated Management of Material Fluxes and of Resources (UNU-FLORES), and the UN Food and Agriculture Organisation (FAO), says these potential supplies can help many of the 1 in 4 people on Earth who face shortages of water for drinking, sanitation, agriculture and economic development.

Based on the most up to date information and data, and with contributions from renowned scientists, experts and practitioners worldwide, the book showcases the potential of different types of unconventional water resources – tapping offshore and onshore deep groundwater, for example, reusing water, moving water physically to water-scarce areas, and more.

Says UNU-INWEH Director Vladimir Smakhtin: “As climate change worsens and with population rising worldwide, water shortages are a top threat to human development and security, making this authoritative analysis of unconventional water resources both timely and important.”

“Harnessing the potential of unconventional water sources could benefit billions of people,” says UNU-INWEH Deputy Director Manzoor Qadir, the book’s lead editor. “These sources will be essential to building a future in arid areas.”

The book identifies six broad categories of unconventional water sources: 

1) Harvesting water from the air with cloud seeding and fog collectors

The atmosphere contains an estimated 13,000 km³ of water vapour, some of which can be captured through cloud seeding and the collection of water from fog and mist.  (A cubic kilometre of water equals the volume of 400,000 Olympic swimming pools, and annual global freshwater demand today is estimated at roughly 4,600 km³ – comparable to the volume of North America’s Lake Michigan, or 1.7 times that of Africa’s Lake Victoria.)

Cloud Seeding or Rain Enhancement 

Cloud seeding can enhance rainfall by up to 15% under the right conditions, and studies show that rain enhancement can work with reasonable cost-benefit ratios. An increasing number of countries plan to carry out rain enhancement in response to water shortages and other societal needs.

Fog Harvesting

Remote communities in Chile, Morocco, and South Africa have used vertical mesh nets to harvest fog for over 100 years, and there are viable sites for fog harvesting on every continent. Advancements in materials and indigenous knowledge have helped develop highly productive, relatively low cost, environmentally-friendly designs to collect potable water – more than 20 litres on a dense fog day for every square metre of mesh.  At an overall cost of less than $250 per square metre of mesh lasting more than a decade, some 75,000 litres per square metre is produced at a cost of just 33 cents a litre.

2) Desalination

Every day desalination contributes over 100 million cubic metres of water, supporting approximately 5% of the world’s population. This volume is projected to double by 2030 while costs will fall by 50%.  New developments in desalination will likely make it the lowest-cost unconventional water supply resource worldwide, particularly in low-income countries where production of desalinated remains far from reality.

While desalination is energy intensive today, innovative technologies such as nanoparticle enhanced membranes and forward osmosis are reducing energy inputs by 20 to 35%. Meanwhile, desalination produces enormous quantities of brine, a pollutant of increasing concern where it is discharged. New technologies that can extract salts, magnesium and other metals from brine to yield commercially-viable products could offset the cost of desalinated water production in the next decade.

3) Reusing water 

Municipal wastewater

Advanced municipal wastewater treatment systems offer a water source while protecting high-quality freshwater surface and groundwater. 

Today around 70% of municipal wastewater in high-income countries is treated, but this falls to only 8% in low-income countries. The annual volume of untreated municipal wastewater is estimated at 171 km³, much of it dumped into the environment, reducing the quality of water in many parts of the world.

Treated wastewater is increasingly used to recharge underground aquifers that supply drinking water in a number of countries. Treated wastewater provides 25% of Windhoek, Namibia’s potable water supply and meets 40% of Singapore’s demand. San Diego, California and other US cities likewise obtain some of their drinking water this way, while Israel and other places use treated wastewater to supply close to a quarter of its agricultural water needs. 

Acceptance of reused wastewater by people and policymakers remains a challenge.

Agricultural drainage water 

Just 1/5th of all cultivated lands are irrigated but they produce 40 percent of the world’s food. Compared to rainfed agriculture, irrigated agriculture is, on average, at least twice as productive per unit of land as it enables production intensification and crop diversification.  And even more food can be grown using the same amount of water through better conservation and reuse of irrigated agricultural drainage water. The latter requires extra care and management as drainage water will always be more saline than the irrigation water from which it is generated. 

Salt-tolerant crops along with new varieties make it increasingly possible to grow crops in saline water. Cyclic and blending are key management options where one field uses the irrigated drainage water from another and then a third uses that drainage water mixed with freshwater. Water and salt from super-saline drainage can be harvested using solar evaporation. 

4) Tapping fresh and brackish groundwater offshore and onshore

The volume of renewable groundwater may be as great as 5 million km³, though much of it tends to be brackish (salty). The seabed near shorelines has considerable volumes of water that is fresh to brackish. 

Offshore 

There are vast quantities (estimated 300,000-500,000 km³) of water in aquifers at shallow depths in continental shelves around the world. These aquifers are less than 100 km offshore, created millions of years ago when sea levels were much lower. 

Some 3,000 years ago, ancient Syrians placed an inverted funnel over a submarine spring offshore to provide about 1,500 litres per second to the city of Tyre. In the 1970s, exploratory drilling offshore of the US eastern seaboard found little oil or gas but did identify vast quantities of fresh to brackish water. Today new marine electromagnetic exploration methods provide detailed images of offshore freshwater. These images, combined with horizontal drilling technologies, can make production of economically significant volumes of freshwater available to be pumped to shore for at least 30 years. To date, no offshore freshwater resources have been developed. 

Inshore Continental Brackish Groundwater Resources 

Deep inland aquifers with brackish or salty water in volumes estimated to total millions of cubic kilometres. As shallow freshwater sources have diminished there has been an exponential growth in brackish water reverse-osmosis desalination plants for drinking water across the United States. In Israel and Spain desalinated water produced from brackish water is also used for production of high value crops. 

Reducing the high costs involved can be accomplished by using electromagnetic surveys to find relatively abundant fresh / brackish water sources and locating desalination facilities there. Improving the efficiency of such facilities will enable broader use of desalinated water in agriculture. Notably, deep underground aquifers can contain hot brackish water that can first be used for geothermal heating in greenhouses and aquaculture facilities and then desalinated, reducing overall costs. 

5) Micro-scale capture of rainwater that would otherwise evaporate

In dry environments over 90% of rainwater is typically lost to evaporation and surface runoff. Micro-catchment rainwater harvesting provides a unique opportunity to capture water for crop production and local needs. It is an ancient practice that employs a wide range of techniques from rooftop and cistern collection to farm and landscape systems including contour ridges, bunds, small runoff basins and strips.  

Even in very dry areas, collecting rainwater from three quarters of the land and using it on the remaining quarter can often provide plenty of water for livestock watering and shrub production.

6) Moving water physically to water-scarce areas in ships’ ballast holds, or towing icebergs

Ballast water 

Ships transport around 90 percent of the goods traded worldwide and discharge some 10 billion tons of ballast water (10 km³) every year. Under the International Convention on the Control and Management of Ships’ Ballast Water and Sediments, all ships of 400 gross tonnage and above must have onboard treatment options to desalinate ballast water, remove invasive aquatic organisms and unhealthy chemical compounds, and is usable for other economic activities such as irrigation. This water could be sold to port cities in arid regions. 

One study estimated that oil tankers and liquefied natural gas (LNG) ships docking in the port city of Abu Dhabi in the United Arab Emirates could transfer their ballast water to an onshore water treatment plant. Ports with onshore desalination facilities could also sell treated ballast water.

Icebergs

The more than 100,000 Arctic and Antarctic icebergs that melt into the ocean each year contain more freshwater than the world consumes. Iceberg-harvesting for freshwater has long been discussed but not seen as practical. However icebergs are towed to supply water to 700 residents of Qaanaaq, Greenland.  Iceberg towing is done in Newfoundland and Labrador to prevent collisions with offshore oil and gas platforms as well as for freshwater and other uses.

Long distance iceberg-towing has never been attempted due to significant loss of water volume and potential breakup of the ice while towing. However a financial feasibility analysis of towing icebergs to Cape Town, South Africa suggests it is an economically attractive option if the icebergs to be towed are big enough, i.e. 125 million tons. Wrapping icebergs in a net and then a mega-bag would likely prevent breakup and reduce melting, studies suggest. Other challenges, however, include turning an iceberg into potable water at its destination and the environmental impacts.

* * * * *

Additional comments

Vladimir Smakhtin, Director, UNU-INWEH (inweh.unu.edu)

“The stark fact is that conventional water provisioning approaches relying on snowfall, rainfall and river runoff are not enough to meet growing freshwater demand in water-scarce areas.  Water scarcity is expected to intensify in regions like the Middle East and North Africa (MENA), which has 6% of the global population but only 1% of the world’s freshwater resources. Climate change adds to this complexity, creating uncertainty and extended droughts, mostly in arid areas.”

“Water-scarce countries need a radical rethink of water resource planning and management that includes the creative exploitation of a growing set of viable but unconventional water resources for food production, livelihoods, ecosystems, climate change adaptation, and sustainable development.”

Manzoor Qadir, Deputy Director, UNU-INWEH

“Water scarcity is ranked among the top 5 in terms of impacts on livelihoods and human wellbeing. By 2030, humanity’s annual global water requirements will exceed current sustainable supplies by 40%, according to one analysis, and almost half of all countries (87 out of 180) are projected to become water-scarce by 2050.”

“The time has come for humanity to tap into the vastly under-used unconventional water sources.  Our book stresses, however, that national water policies and action plans to tap these sources will first require local assessments of the environmental trade offs.  And a prerequisite for that in many places will be greater institutional and human capacity to evaluate potential unconventional water source uses, including comprehensive cost analyses.  Innovative financing mechanisms will also be needed.” 

Edeltraud Guenther, book co-Editor and Director, UNU-FLORES (flores.unu.edu)

“Increasing water scarcity is now recognized as a major cause of conflict, social unrest and migration and at the same time water is increasingly considered as an instrument for international cooperation to achieve sustainable development. When exploiting unconventional water resources, we often focus on the costs of actions only. But we have to calculate the costs of inaction as well, and we have to explore opportunities to transfer or shift costs to other stakeholders, consumers or the government. Tapping and assessing sustainably every available option in water-scarce areas is needed as pressure continues to build on limited water resources.”

Sasha Koo-Oshima, book co-Editor and Deputy Director, UN FAO (fao.org) 

“The increasing pressures on water resources requires a new era of water management, one that addresses barriers to efficient water management and ensures that water in all its forms is monitored and accounted for, including its value to food, ecosystems and health, and its role in supporting food security and basic needs of humanity and economic development.”

* * * * * 

Media coverage highlights:

The Hill, via Yahoo! News, United States (62,797,142), UN experts call upon nations to tap ‘unconventional water resources’

Deutsche Presse Agentur via DIE WELT, Germany (16,239,674)
Wasserknappheit: Experten wollen andere Quellen Nutzen (Water scarcity: experts want to use other sources) 

Agencia EFE, Spain, De la atmósfera a los icebergs: Las nuevas fuentes para buscar agua (From the atmosphere to icebergs: The new sources to search for water) 

Libération, France (6,275,441), Icebergs, nuages, eaux usées… les 6 solutions «non conventionnelles» de l’ONU pour pallier au manque d’eau potable (Icebergs, clouds, waste water… the 6 “unconventional” solutions of the UN to overcome the lack of drinking water)

Público, Portugal (3,029,407)
Chegou a hora de aproveitar as fontes de água menos convencionais. Porque cada gota conta (The time has come to take advantage of less conventional water sources. ‘Cause every drop counts)

Interesting Engineering, Canada (2,501,776)
United Nations: Harvesting new water sources can benefit ‘billions of people’

Down To Earth, India (1,046,015) Icebergs and fog: These unconventional sources can help beat global water scarcity 

MeteoWeb, Italy (1,074,200) Le proposte dell’Onu: “prendere acqua da nebbia e iceberg contro la crisi idrica” The UN proposes “take water from fog and icebergs against the water crisis” 

CCTV 央视网, Mainland China (22,026,184) 淡水缺了 “非常规水源”来补 (“Unconventional water sources” to make up fresh water shortages 

China News Network, Mainland China (5,659,775) 非常规水源”，潜在水供应或可助全球四分之一人口 (Potential water supply from ‘unconventional sources’ could help a quarter of the world’s population)

Coverage summary in full, click here

News release in full, click here

1st assessment of water security in Africa is based on 10 indicators

Despite global Sustainable Development Goals and commitments made in 2015, just 29 African nations have made some progress over the past three to five years, 25 have made none, according to the UN’s first-ever assessment of water security in Africa.

Published on the eve of World Water Day (March 22) by UN University’s Canadian-based Institute for Water Environment and Health, the assessment employed 10 indicators to quantify water security in Africa’s 54 countries.  Water security is elaborated below.

UNU-INWEH authors Grace Oluwasanya, Duminda Perera, Manzoor Qadir and Vladimir Smakhtin, the Institute’s Director, say the assessment is limited by “very poor” data on water security-related issues such as access to drinking water or sanitation, but it nevertheless offers some “preliminary but obvious conclusions.”

“Data limitations do not change the main outcome of this assessment, which is strong and clear,” says lead author Grace Oluwasanya.  “Overall levels of water security in Africa are low. Not a single country let alone a subregion have at present achieved a state that can be seen as ‘model’ or even ‘effective’ stage of water security.”

Says co-author Duminda Perera: “This assessment for African countries aimed to create a quantitative starting point and a platform for subsequent discussions with national, regional and international agents; it is neither a prescription nor a guide.”

“As this quantitative tool develops, it will help generate targeted policy recommendations and inform decision-making and public-private investments toward achieving water security in Africa.”

Results in brief

Overall

Except for Egypt, all country scores are below 70 (on a scale of 100). Only 13 of 54 countries reached a modest level of water security in recent years, and over a third are deemed to have levels of water security below the threshold of 45.  

Together, the 19 countries below the threshold are home to half a billion people.

Egypt, Botswana, Gabon, Mauritius and Tunisia are Africa’s top five most water-secure countries in Africa, yet with only modest absolute levels of water security achieved. 

Somalia, Chad and Niger appear to be the least water-secure countries in Africa. 

There has been little progress in national water security of most African states over the past three to five years, the report finds. The number of countries that made some progress (29) is close to the number of those that made none (25).

Indicator 1 

Access to drinking water ranged from 99% in Egypt to 37% in the Central African Republic, and between subregions from 92% in North Africa to 62% in Central Africa. Africa’s average basic drinking water service is 71%, “leaving behind some 29% of the total population” or more than 353 million people. 

Indicator 2 

Access to sanitation is broadly similar at the subregional level, but a few countries — Seychelles and most countries in North Africa countries — have reached or nearly reached 100%. The most challenged countries are Chad and Ethiopia (under 20% access), with 60% average access to even limited sanitation; thus at least 40% of the total population (483 million people) are left behind. 

Indicator 3

Access to hygiene facilities and practices (e.g. hand washing) are greatest in North Africa (67%), worst in West Africa (with Rwanda, Liberia lowest among eight countries with less than 10% access; Chad and the Central African Republic suffer the highest number of deaths from diarrhea).

Indicator 4

Per capita water availability is highest in Central Africa (with the Republic of Congo considered Africa’s most water-rich country — over 31,000 cubic meters per capita), while half of North African countries appear to be absolutely water scarce — less than 500 cubic meters of water per capita per annum. Due to their population growth, water availability has recently declined in West, Central and Southern Africa sub-region, and, on a country scale, in Ivory Coast, Cameroon, Somalia, Mozambique, and Malawi.

Indicator 5

Water use efficiency appears to be lowest in North Africa (with Somalia lowest at the national level) highest in Central Africa (with Angola highest at a national level). In general, agriculture-dominant countries score lower.  An improvement seen in water use efficiency in Africa as a whole is primarily due to efforts in Tunisia, Gambia, Burkina Faso, Rwanda, and Uganda, but poor data quality makes assessment difficult.

Indicator 6

Water infrastructure is deemed best in the Southern Africa sub-region, worst in East Africa. South Africa, with over 25% of all large dams in Africa, is outscored by Ghana, Zimbabwe, and Zambia, likely due to just one mega reservoir in those countries. Half of all countries score very low, reflecting the continent’s low level of water storage development. Only Ethiopia and Namibia have increased their storage over recent years, while Ivory Coast and Gabon have shown a decline, partly explained by rising populations with no or minimal increase in storage. Africa-average per capita storage capacity increased by only 3% over five recent years. 

Indicator 7

Wastewater treatment scores are highest in North African countries, lowest in East and West Africa, where 12 countries in each region treat less than 5% of wastewater. No country treats more than 75%, only Tunisia, Egypt and Lesotho treat over 50% and 67% of African countries treat less than 5%. The issue is poorly tracked in Africa overall. 

Indicator 8

Water governance appears to be most advanced in North and Southern Africa sub-regions, while Central Africa the least advanced. Nationally, Ghana reported reaching 86% of Integrated Water Resource Management (IWRM) implementation, a significant improvement in just two years. Liberia, Guinea-Bissau, and Comoros are the lowest-performing countries, but again the assessment may be affected by the quality of national reporting. 

Indicator 9

Disaster risk has either remained unchanged (North and Southern Africa sub-regions) or increased. North Africa appears to be the least risky subregion, West Africa the riskiest. Egypt appears to be the least risky country, while Cape Verde is the most, followed by Djibouti and Comoros. Some 49 of 54 African countries have seen increased disaster risk scores over five recent years, explained by the impacts of changing climate worsening countries’ exposure to natural disasters and outpacing their ability to adapt. 

Indicator 10

Water dependency on neighboring nations and water resources variability:  Egypt stands out as Africa’s most water-dependent country; the Southern Africa sub-region has the most variable water resources. Naturally existing physiographic conditions may, to an extent, determine how much effort is needed for a country to achieve higher levels of water security. 

Call for global standards

To compare Africa’s situation globally, the authors call for global standards for water security measurement data and assessment. 

“Some critical components of water security simply cannot be assessed without introducing surrogates or proxies,” as used in the report in the case of drinking water and sanitation, for example. 

“With such poor data availability, progress toward water security is difficult to assess accurately.” 

For example, it is not possible to estimate the percentage of the African population that will have access to safely managed drinking water services or safely managed sanitation by 2030, a key UN Sustainable Development Goal globally agreed in 2015. 

“Data availability – or the lack of it – in itself may be an excellent indicator of water security,” says Dr. Oluwasanya. “Action needs to be taken immediately by national governments with support from international agents to radically improve data collection efforts for Africa.”

What is water security?

The UN’s concept of water security encompasses various needs and conditions — water for drinking, economic activity, ecosystems, hazard resilience, governance, transboundary cooperation, financing, and political stability.

See https://bit.ly/3hUzIh4

Hence water security is not just about how much natural water a country has but also how well the resource is managed.  It is defined as “The capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water for sustaining livelihoods, human well-being, and socio-economic development, for ensuring protection against water-borne pollution and water-related disasters, and for preserving ecosystems in a climate of peace and political stability.”

UNU-INWEH led the UN’s development and definition of water security and its related tools are now the most widely-accepted in the world.  This was a fundamental milestone, contributing to conceptualization of the SDGs and to on-going efforts to assess national water security in a quantifiable way.

The assessment tool is still a work in progress, Dr. Smakhtin notes, adding that UNU-INWEH’s goal is to have by 2025 — five years before the deadline for meeting the UN’s Agenda 2030 — “an improved, influential and nationally-owned tool” for assessing water security in all African countries. 

* * * * *

About UNU and UNU-INWEH 

The United Nations University (UNU), an academic arm of the UN, includes 13 institutes and programmes located in 12 countries around the world, and dealing with various issues of development.

UNU-INWEH was established as a public service agency and a subsidiary body of the UNU, in 1996. Its operations are secured through long-term host-country and core-funding agreements with the Government of Canada.

The Institute is located in Hamilton, Canada, and its facilities are supported by McMaster University. 

UNU-INWEH’s mission is to help resolve pressing water challenges that are of concern to the United Nations, its Member States, and their people, through critical analysis and synthesis of existing bodies of scientific discovery; targeted research that identifies emerging policy issues; application of on-the-ground scalable science-based solutions to water issues; and global outreach. 

UNU-INWEH carries out its work in cooperation with the network of other research institutions, international organisations and individual scholars throughout the world. 

* * * * *

Media coverage highlights:

New York Times, United States (181,487,873): Climate change is making armed conflict worse. Here’s how. Click here

Reuters, United Kingdom, Africa’s water security perilous – but data reveals surprises, click here

Agencia EFE, Spain (via e.g. Infobae, Argentina, 49,192,499)
1) Some 500 million people live in Africa without water security, click here
2) Spanish: Unos 500 millones de personas viven en África sin seguridad del agua, click here
3) Russian, click here

The Hill, United States (15,808,772): 500 million people in Africa remain ‘water insecure’: UN report, click here (also distributed via MSN, United States (198,375,148) and Yahoo News, United States (61,261,480)

ORF Online, Austria (7,871,539), Jedes dritte Land ohne Wassersicherheit, click here

Deutsche Press Agentur, via e.g. Handelsblatt, Germany (6,134,345), UN: Mehr als ein Drittel der Länder in Afrika ohne Wassersicherheit, click here

Xinhua (新华网), Mainland China (4,312,277), UN report says Africa’s fragile water security a threat to sustainability agenda, click here

IndoAsian News Service, India (via ProKerala, 10,631,550)25 African nations ‘least’ water-secure, click here

Agenzia Giornalistica Italia, Italy (4,066,652)Rischio acqua per oltre mezzo miliardo di persone in Africa, click here

France 24 (EN) France (2,853,455), Eye on Africa video program – Water security in Africa ‘unacceptably low’ (UN), click here

Spektrum der Wissenschaft, Germany (4,274,603), click here

Diario de Sevilla, Spain: Alrededor de 500 millones de personas viven en África sin seguridad del agua, click here

* * * * *

Mainstream media coverage summary, click here

News release in full, click here

• See also: “Popular Science Magazine: UN’s World Flood Mapping Tool is One of 2021’s 100 Greatest Innovations,” click here

Developed by UN University with Google and other partners, free online World Flood Mapping Tool will help plan urban and agricultural development, effective flood defences, disaster readiness, identify supply chain vulnerabilities

UN University-led experts have debuted a new tool that generates instant, accurate street-level resolution maps of floods worldwide since 1985.  The free online World Flood Mapping Tool will help all countries but especially those in the Global South, where flood risk maps are rare and often badly out of date.

Created by the UN University’s Institute for Water, Environment and Health in Hamilton, Canada, with support from Google, MapBox and other partners listed below, the tool lets users adjust variables to help locate gaps in flood defences and responses, and to plan future development of all kinds — for example, where to build or upgrade infrastructure, or develop agriculture. 

Simple to use, the tool, at https://floodmapping.inweh.unu.edu, requires only Internet access to obtain a flood map at 30-meter resolution — street by street level.  An upcoming version for more commercial uses, for example by insurance firms, will offer even more precise building-level resolution. 

The tool allows users to adjust variables to help locate gaps in flood defences and responses, and to plan future development of all kinds — for example, where to build or upgrade infrastructure, or develop agriculture. 

Says UNU-INWEH Director Vladimir Smakhtin: “Floods in the past decade have impacted the lives of more than half a billion people, mainly in low and middle income countries, and resulted in damages of nearly US $500 billion — roughly equal to the GDP of Singapore.  More recent floods worldwide have added to a fast growing toll of upended lives, damage and deaths.”

“An estimated 1.5 billion people — greater than the population of Europe — live at risk of exposure to intense flooding,” adds Dr. Smakhtin. “We need to prepare now for more intense and more frequent floods due to climate change and hope this tool will help developing nations in particular to see and mitigate the risks more clearly.”

Hamid Mehmood, a GIS and remote sensing specialist at UNU-INWEH who led the tool’s development, says that a UNU-INWEH survey showed a majority of flood forecasting centers in flood-prone countries lack the ability to run complex flood forecasting models.

He adds that floods like those this year in Europe that killed more than 200 people and caused billions of dollars in damages are now up to nine times more likely because of climate change. 

“As temperatures continue to rise the number of flood events will increase along with their severity,” he said.  “No place is immune. And yet remarkably few regions, even in wealthy countries, have useful, up-to-date flood maps because of the cost and difficulty of creating them.”

The World Flood Mapping Tool uses the Google Earth Engine combined with decades of Landsat data since 1985 — a vast catalog of geospatial data enabling planet-scale analysis capabilities. 

Layers of Landsat information for a selected region and specified timeframe identifies temporary and permanent water bodies while integrating site-specific elevation and land-use data. 

This produces a detailed map of flood inundation in recent decades, with available overlays of population, buildings and land use, which can be used for community planning, building zoning, insurance assessments and more.

To validate the technology, maps generated in less than a minute using the new tool were compared to documented flooding events in Australia, Bangladesh, Canada, Cambodia, India, Mozambique, Sri Lanka and Thailand (detailed below), with 82% accuracy achieved.

Wikipedia’s list of history’s deadliest floods (here) shows 211 events, 103 of which occurred from 1985, the first year covered by the new tool’s data.

The new tool will also reflect new floods soon after they occur to provide the most up-to-date maps to help assess overall flood impacts and plan for the future.

“Painting a detailed picture of the historical and potential flood risk areas will be invaluable for any urban and regional planning department,” says project collaborator Dr. Duminda Perera of UNU-INWEH.

The more detailed version of the tool in development for commercial use will provide resolution at a building-by-building level and incorporate building occupancy data.

And a free flood risk prediction tool for release next year will use artificial intelligence to generate current and future flood risk maps for three climate change scenarios at the city, district, and river basin levels.

Maximizing the effectiveness of investments in public infrastructure and reducing costs

Reliable up-to-date information about areas at risk of flooding is especially valuable in Africa and Southeast Asia, where urban areas are expected to grow 80% by 2030. The tool can show the flood-safe locations for housing and industry as well as improving overall urban planning.

The new World Flood Mapping Tool enables governments, funding agencies, and disaster management authorities to hone in on the highest potential risk locations of flooding in the future. Knowing exactly where flooding will occur can maximize the effectiveness of investments in public infrastructure and reduce costs.

It differs from previously available systems in a number of ways, including: 

• Improved resolution of inundation maps to 30 meter resolution, enabling analysis at a citywide level
• Focus on the Global South, where data and information gaps are prominent and annual losses due to floods are high
• Improved accuracy of inundation maps using data from multiple satellite sensors
• Improved accuracy and shorter development time of flood risk maps by using AI models

Dr. Mehmood adds that natural disaster-related insurance rates (where such insurance exists for homes and livelihoods impacted by flooding), flood-related human and economic losses, etc., can be estimated using the new tool. 

Potential supply chain vulnerabilities can be revealed. And during disasters, the tool can be used to help determine emergency relief routes.

The World Flood Mapping Tool could also potentially guide development of agriculture insurance support for persons living and farming at the subsistence level. Creating this safety net would have far-reaching implications for global development goals and promoting more secure economies and nations.

The flood inundation maps generated by the tool can be merged with other open datasets — population density or land use / land cover changes, for example — enabling a variety of ways to peer into the future. 

Adding other remote-sensing datasets will also improve the tool and offer new ways to employ it, all of which strengthens the ability of countries in the Global South and elsewhere to better plan for and respond to disasters.

* * * * * 

Partners

UN: 

UNESCO Madanjeet Singh Centre for South Asia Water Management, Sri Lanka

Government: 

Water Resources Research and Development Centre, Nepal

Directorate of Planning, Bangladesh

Private Sector: 

Google, in-kind support under their their Google Cloud for Researchers program

MapBox, in-kind support under their Education program 

Civil Society: 

Asian Disaster Preparedness Center, Thailand

Network of Disaster Management Practitioners, Pakistan

Academia: 

McMaster University, Canada

International Institute of Information Technology, India

* * * * *

Background

The following case studies were used to validate the accuracy of the new flood mapping tool:

Australia, Queensland, 11 – 18 February, 2008

Severe weather and intense rain hit the central coast of Queensland, where some rainfall stations received over 600 mm of rain in just six hours.  Insurance companies paid out roughly US $297 million, and road and drainage infrastructure repairs cost an estimated US $32 million.

Bangladesh, Dhaka, 2017

Three major flood events affected over 8 million people and caused loss of life, severe damage to housing, infrastructure, and affected crops and livestock throughout the country. The flood event studied resulted from heavy rains from late March to early April, with a focus on the country’s northeastern region, where over 850,000 households were impacted, and 220,000 acres of ready-to-harvest rice were damaged.

Cambodia, Phnom Penh, 2011

Flooding affected 18 of 24 provinces in 2011, damaged infrastructure and agriculture, jeopardized food security, and directly impacted over 1.2 million people.

Canada, Red River, April 2019

The Red River, which originates from Minnesota and North Dakota and flows northwards through Manitoba to Hudson Bay, flooded extensively in 1950 and 2011. The study area focused on the agricultural land and small communities between Winnipeg and the US border flooded in April 2019.

India, Bihar, April 2017

Floods caused by excess rainfall during the monsoon season in April 2017 affected 19 districts of North Bihar, caused 500 deaths and impacted around 17 million people

Mozambique / Malawi, March 2015

Near Mozambique’s border with Malawi, a flood in March 2015 occurred shortly after two tropical cyclones hit. Over 530,000 people were affected, about 30,000 displaced and 37 died.  Cascading post-disaster events included an outbreak of cholera that ravaged the already badly-affected communities

Sri Lanka, Colombo, May 2016

A tropical storm in May 2016 impacted 22 of 25 districts in the country and caused widespread flooding and landslide devastation. Over 300,000 people were affected, with 203 listed as dead or missing

Thailand, Pathumthani and Bangkok, 2011

In 2011 Thailand recorded record high rainfall during the monsoon season, immediately followed by four tropical storms in the north. River banks burst and releases of water from upstream dams exacerbated flooding that persisted for over 150 days.  The floods inundated over 30,000 square km and caused roughly US $900 million in losses (US $360 in insured losses).

About the United Nations University Institute for Water, Environment and Health: Inweh.unu.edu

UNU-INWEH is supported by the Government of Canada through Global Affairs Canada and hosted by McMaster University

Media coverage highlights

Daily Mail, United Kingdom, Earth’s floods mapped: UN develops an interactive tool that reveals street-level resolution maps of floods worldwide since 1985, click here

The Independent, United Kingdom, UN map tool shows every flood in the world since 1985, click here

Newswires

Europa Press, newswire, Spain: Ciencia.-Nueva herramienta de la ONU cartografía las inundaciones desde 1985, click here

United Press International, United States: Flood mapping New U.N. tool designed to enhance flood prediction, disaster planning, click here

Agencia EFE, via Diario Libre, United States: Una herramienta en línea de la ONU permitirá planificar inundaciones, click here

Europa Press, Spain (via Infobae, Argentina): Nueva herramienta de la ONU cartografía las inundaciones desde 1985, click here

IndoAsian News Service (IANS, via ProKerala, India): UN tool maps floods worldwide since 1985, click here

PPB newswire, Indonesia (via WowKeren, Indonesia): Kembangkan Alat Baru Prediksi Banjir, Bisa Diakses Gratis!, click here

Akhbar el-Yom- بوابة أخبار اليوم الإلكترونية, Egypt: تطوير أداة تفاعلية تحدد موقع الفيضانات بالشوارع منذ عام 1985, click here

Coverage summary, click here

News release in full, click here

Media worldwide have often helped communicate UNU-INWEH’s scientific and policy-relevant discoveries and insights to the general public and important decision-making audiences worldwide.

With thanks to the hundreds of reporters and thousands of news editors involved, UNU-INWEH top news making highlights in its first 25 years are showcased in a colourful presentation.

Click here

Increasingly expensive to maintain, experts foresee a trend to decommissioning dams

By 2050, most people on Earth will live downstream of tens of thousands of large dams built in the 20th century, many of them already operating at or beyond their design life, according to a UN University analysis.

The report, “Ageing water infrastructure: An emerging global risk,” by UNU’s Canadian-based Institute for Water, Environment and Health, says most of the 58,700 large dams worldwide were constructed between 1930 and 1970 with a design life of 50 to 100 years, adding that at 50 years a large concrete dam “would most probably begin to express signs of aging.”

Ageing signs include increasing cases of dam failures, progressively increasing costs of dam repair and maintenance, increasing reservoir sedimentation, and loss of a dam’s functionality and effectiveness, “strongly interconnected” manifestations, the paper says.

The report says dams that are well designed, constructed and maintained can “easily” reach 100 years of service but predicts an increase in “decommissioning” — a phenomenon gaining pace in the USA and Europe — as economic and practical limitations prevent ageing dams from being upgraded or if their original use is now obsolete.

Worldwide, the huge volume of water stored behind large dams is estimated at 7,000 to 8,300 cubic kilometres — enough to cover about 80% of Canada’s landmass under a meter of water.

The report provides an overview of dam ageing by world region and primary function — water supply, irrigation, flood control, hydropower, and recreation.

It also details the increasing risk of older dams, the rising maintenance expense, the declining functionality due to sedimentation, the benefits of restoring or redesigning natural environments, and the societal impacts — pro and con — that need to be weighed by policymakers deciding what to do. Notably, “the nature of these impacts varies significantly between low- and high-income countries.”

The analysis also includes dam decommissioning or ageing case studies from the USA, France, Canada, India, Japan, and Zambia & Zimbabwe.

Climate change will accelerate the dam ageing process

“This report aims to attract global attention to the creeping issue of ageing water storage infrastructure and stimulate international efforts to deal with this emerging, rising water risk,” says co-author Vladimir Smakhtin, Director of UNU-INWEH.

“Underlined is the fact that the rising frequency and severity of flooding and other extreme environmental events can overwhelm a dam’s design limits and accelerate a dam’s ageing process. Decisions about decommissioning, therefore, need to be taken in the context of a changing climate.”

Notes lead author and UNU-INWEH Senior Researcher Duminda Perera: “This problem of ageing large dams today confronts a relatively small number of countries — 93% of all the world’s large dams are located in just 25 nations.”

“Large dam construction surged in the mid-20th century and peaked in the 1960s – 70s,” he says, “especially in Asia, Europe and North America, while in Africa the peak occurred in the 1980s. The number of newly-constructed large dams after that continuously and progressively declined.”

According to the report, the world is unlikely to witness another large dam-building revolution as in the mid-20th century, but dams constructed then will inevitably be showing their age.

China has 23,841 large dams (40% of the world’s total). And 32,716 large dams (55% of the world’s total) are found in just four Asian countries: China, India, Japan, and the Republic of Korea — a majority of which will reach the 50-year threshold relatively soon. The same is true of many large dams in Africa, South America, and Eastern Europe.

The pace of large dam construction has dropped dramatically in the last four decades and continues to decline in part because “the best locations for such dams globally have been progressively diminishing as nearly 50% of global river volume is already fragmented or regulated by dams,” the report says.

As well, there are strong concerns regarding the environmental and social impacts of dams, and large dams in particular, as well as emerging ideas and practices on the alternative types of water storage, nature-based solutions, and types of energy production beyond hydropower.

Drivers of dam decommissioning

Public safety, escalating maintenance costs, reservoir sedimentation, and restoration of a natural river ecosystem are among the reasons driving dam decommissioning.

However, most dams removed to date have been small; decommissioning large dams (defined by ICOLD as 15 or more metres from lowest foundation to crest, or 5 to 15 metres impounding more than 3 million cubic metres) is “still in its infancy, with only a few known cases in the last decade.”

“A few case studies of ageing and decommissioned large dams illustrate the complexity and length of the process that is often necessary to orchestrate the dam removal safely,” adds co-author and UNU-INWEH Adjunct Professor R. Allen Curry, based at the University of New Brunswick.

“Even removing a small dam requires years (often decades) of continuous expert and public involvement, and lengthy regulatory reviews. With the mass ageing of dams well underway, it is important to develop a framework of protocols that will guide and accelerate the dam removal process.”

Decommissioning will also have various positive and negative economic, social, and ecological impacts to be considered in a local and regional social, economic, and geographic context “critical to protect the broader, sustainable development objectives for a region,” the report says.

“Overall, dam decommissioning should be seen as equally important as dam building in the overall planning process on water storage infrastructure developments.”

“Ultimately, value judgments will determine the fate of many of these large water storage structures. It is not an easy process, and thus distilling lessons from and sharing dam decommissioning experiences should be a common global goal. Lack of such knowledge and lack of its reflection in relevant regional/national policies/practices may progressively and adversely affect the ability to manage water storage infrastructure properly as it is ageing.”

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In addition to the three UNU-INWEH experts, the report was co-authored by Spencer Williams, Graduate Institute of International and Development Studies, Geneva, Switzerland. and Taylor North of McMaster University, Hamilton, Canada.

The report is available post-embargo at http://bit.ly/UNU-dams

By the numbers

General

58,700: large dams registered in the International Commission on Large Dams (ICOLD) database, a large dam is defined as 15+ metres in height, measured from lowest foundation to crest, or 5 to 15 metres high impounding more than 3 million cubic metres (0.003 km3). Within the 58,700 large dam total, roughly one in eight has a 100 million cubic metre (0.1 km3) capacity

7,000 to 8,300 km3: volume of water stored behind large dams worldwide — about one-sixth of all river discharge worldwide each year — enough to cover roughly 80% of Canada’s landmass under a meter of water

50 to 100 years: design life of dams constructed between 1930 and 1970 (when most existing large dams were built). Average life expectancy: 50 years

~16,000: large dams 50 to 100 years old in North America and Asia
~2,300: large dams 100+ years old in North America and Asia

USA / Canada

56: average age of 90,580 US dams (all sizes)

85%+: US dams in 2020 operating at or beyond their life expectancy

75%: US dam failures that occurred after 50 years of age

US$ 64 billion: estimated cost to refurbish US dams

1,275: dams removed in 21 US states in the last 30 years; 80 removed in 2017 alone

50%+: large dams in Canada over 50 years old

Asia / Pacific

China

56%: proportion of the world’s large dams located in China and the US (the top 25 countries account for more than ~93%)

23,841: large dams in China (the most of any country, and 40% of the world’s total
60%: proportion of the world’s large dams in Asia
55%: proportion of the world’s large dams in just four countries — China, India, Japan, and the Republic of Korea — the majority of which will soon reach 50 years of age

India

1,115+: large dams in India that will be roughly 50 years old in 2025
4,250+: large dams in India that will be 50+ years old in 2050
64: large dams in India that will be 150+ years old in 2050
3.5 million: the approximate number of people at risk if India’s Mullaperiyar dam, built 100+ years ago, were to fail. The dam, in a seismically active area, shows significant structural flaws and its management is a contentious issue between Kerala and Tamil Nadu States

Japan

100+ years: average age of large dams in Japan

Australia

650: large dams in Australia, half of them 50+ years old; 50+ have been in operation for 100+ years. Portion of Australia’s clean energy generated from hydropower: 65%

UK / Europe

100+ years: average age of large dams in the UK

~10%: large dams in Europe 100+ years old

Africa

2,000: large dams in Africa (¼ of them in South Africa), the fewest of any continent; mostly used for irrigation

UNU-INWEH (inweh.unu.edu) is supported by the Government of Canada through Global Affairs Canada, and hosted by McMaster University, Hamilton, Canada

UNU-INWEH’s Water Learning Centre (http://bit.ly/wlc-unu-inweh) offers free courses to university students and practicing water professionals looking to strengthen their capacity in several focused and multidisciplinary learning areas.

Coverage highlights

Agence France Presse, France
World’s aging big dams pose ’emerging risk’: UN
https://www.ctvnews.ca/climate-and-environment/world-s-aging-big-dams-pose-emerging-risk-un-1.5278178
French version: La vétusté des barrages fluviaux est un risque émergent, estime l’ONU
https://actu.orange.fr/societe/environnement/la-vetuste-des-barrages-fluviaux-est-un-risque-emergent-estime-l-onu-CNT000001wAWEn.html

Agencia EFE, Spain
El envejecimiento de miles de grandes embalses es un creciente problema mundial
https://www.infobae.com/america/agencias/2021/01/22/el-envejecimiento-de-miles-de-grandes-embalses-es-un-creciente-problema-mundial/

Europa Press, Spain
La mayor parte de la Humanidad vivirá amenazada por viejas presas para 2050
https://www.europapress.es/ciencia/habitat/noticia-mayor-parte-humanidad-vivira-amenazada-viejas-presas-2050-20210122180412.html

Press Trust of India
Ageing dams in India, US, other nations pose growing threat: UN report
https://timesofindia.indiatimes.com/india/ageing-dams-in-india-us-other-nations-pose-growing-threat-un-report/articleshow/80433078.cms

Agenzia Giornalistica Italia, Italy
Le dighe invecchiano, allarme dell’Onu sulla manutenzione
https://www.agi.it/estero/news/2021-01-24/clima-dighe-invecchiano-e-urge-manutenzione-allarme-onu-11137456

SINC (Spanish Scientific News Agency), Spain
Las presas envejecidas se convierten en una amenaza creciente
https://www.virtualpro.co/noticias/las-presas-envejecidas-se-convierten-en-una-amenaza-creciente

Indo-Asian News Service (IANS), India
Ageing, unsafe dams growing threat in India too: UN report
https://www.nationalheraldindia.com/environment/ageing-unsafe-dams-growing-threat-in-india-too-un-report

News sites

Guardian, UK
UN warns most will live downstream of ageing large dams by 2050
https://www.theguardian.com/environment/2021/jan/22/un-warns-most-will-live-downstream-ageing-large-dams-2050

Daily Mail, UK
Most of the world’s 58,000 biggest dams are crumbling, report warns
https://www.dailymail.co.uk/sciencetech/article-9176301/Most-worlds-58-000-biggest-dams-crumbling-report-warns.html

China Global Television Network (CGTN)
Aging dams pose grave threat as climate change tests their strength
https://news.cgtn.com/news/2021-01-22/Aging-dams-pose-grave-threat-as-climate-change-tests-their-strength-Xb7uC5mNKU/index.html

Kompas, Indonesia
Puluhan Ribu Bendungan Besar Dunia Mulai Menua, Apa Dampaknya?
https://www.kompas.com/tren/read/2021/01/24/123000265/puluhan-ribu-bendungan-besar-dunia-mulai-menua-apa-dampaknya-

ReliefWeb (UN Office for the Coordination of Humanitarian Affairs), United States
Ageing Water Storage Infrastructure: An Emerging Global Risk
https://reliefweb.int/report/world/ageing-water-storage-infrastructure-emerging-global-risk

Clarín, Argentina
Próximo peligro para la humanidad: los 60.000 viejos embalses que hay en el mundo
https://www.clarin.com/viste/proximo-peligro-humanidad-60-000-viejos-embalses-mundo_0_w2tvUidTf.html

Eco-Business, Singapore
Retiring ageing hydropower dams could protect people and budgets. But aren’t they needed in the energy transition?
https://www.eco-business.com/news/retiring-ageing-hydropower-dams-could-protect-people-and-budgets-but-arent-they-needed-in-the-energy-transition/

Radio France International
Online: Are Africa’s Ageing Dams Doomed?
https://www.modernghana.com/news/1057391/are-africas-ageing-dams-doomed.html 
Audio: https://www.rfi.fr/en/africa/20210125-are-africa-s-ageing-dams-doomed-united-nations-water-environment-health-safety-report

News release in full, click here

Coverage summary, click here

Enough energy to power all households in the USA and Mexico; enough nutrients to meet ~13% of world fertilizer needs; enough water to fill Lake Victoria in seven years, Lake Ontario in four; UN University foresees 24% wastewater rise by 2030; 51% by 2050

Vast amounts of valuable energy, agricultural nutrients, and water could potentially be recovered from the world’s fast-rising volume of municipal wastewater, according to a new study by UN University’s Canadian-based Institute for Water, Environment and Health (UNU-INWEH).

Today, some 380 billion cubic meters (m3 = 1000 litres) of wastewater are produced annually worldwide – 5 times the amount of water passing over Niagara Falls annually – enough to fill Africa’s Lake Victoria in roughly seven years, Lake Ontario in four, and Lake Geneva in less than three months.

Furthermore, the paper says, wastewater volumes are increasing quickly, with a projected rise of roughly 24% by 2030, 51% by 2050.

Today, the volume of wastewater roughly equals the annual discharge from the Ganges River in India. By the mid-2030s, it will roughly equal the annual volume flowing through the St. Lawrence River, which drains North America’s five Great Lakes.

Among major nutrients, 16.6 million metric tonnes of nitrogen are embedded in wastewater produced worldwide annually, together with 3 million metric tonnes of phosphorus and 6.3 million metric tonnes of potassium. Theoretically, full recovery of these nutrients from wastewater could offset 13.4% of global agricultural demand for them.

Beyond the economic gains of recovering these nutrients are critical environmental benefits such as minimizing eutrophication – the phenomenon of excess nutrients in a body of water causing dense plant growth and aquatic animal deaths due to lack of oxygen.

The energy embedded in wastewater, meanwhile, could provide electricity to 158 million households – roughly the number of households in the USA and Mexico combined.

The study’s estimates and projections are based on theoretical amounts of water, nutrients, and energy that exist in the reported municipal wastewater produced worldwide annually.

The authors underline that information on wastewater volumes — generated, available, and reused – is scattered, infrequently monitored and reported, or unavailable in many countries. They also acknowledge the limitations of current resource recovery opportunities.

Nonetheless, says lead author Manzoor Qadir, Assistant Director of UNU-INWEH, in Hamilton, Canada: “This study offers important insights into the global and regional potential of wastewater as a source of water, nutrients, and energy. Wastewater resource recovery will need to overcome a range of constraints to achieve a high rate of return but success would significantly advance progress against the Sustainable Development Goals and others, including adaptation to climate change, ‘net-zero’ energy processes, and a green, circular economy.”

Among many findings:

• The energy value in 380 billion m3 of wastewater is estimated to be 53.2 billion m3 methane – enough to provide electricity for up to 158 million households, or 474 million to 632 million people, assuming an average of three to four persons per household. Given the foreseen wastewater increases, that number rises to 196 million households in 2030, and 239 million households in 2050.
• In agriculture, the volume of water potentially recoverable from wastewater could irrigate up to 31 million hectares – equal to almost 20% of the farmland in the European Union (assuming two crops and a maximum 12,000 m3 of water per hectare per year). “The reclaimed water can be used to irrigate new areas or replace valuable freshwater where crops are already irrigated.”
• World wastewater production is expected to reach 470 billion m3 by 2030, the year by which the SDGs are supposed to be met – a 24% increase from today. And by 2050, it will reach 574 billion m3, a 51% increase.
• Asia is the largest wastewater producer with an estimated 159 billion cubic meters, representing 42% of urban wastewater generated globally, with expectations of that proportion rising to 44% by 2030
• Other regions producing large volumes of wastewater: North America (67 billion m3) and Europe (68 billion cubic meters) – virtually equal volumes despite Europe’s higher urban population (547 million vs. North America’s 295 million. The difference is explained by per capita generation of wastewater: Europe 124 cubic meters; North America 231 cubic meters). By contrast, Sub-Saharan Africa produces 46 cubic meters of wastewater per capita – about half of the global average (95 cubic meters), reflecting limited water supply and poorly-managed wastewater collection systems in most urban settings.
• Full recovery from wastewater could, theoretically, offset 14.4% of global demand for nitrogen as a fertilizer nutrient; phosphorus 6.8% and potassium 18.6%. Based on current levels of nitrogen, phosphorus, and potash use in agriculture worldwide (estimated at 193 million metric tonnes in 2017), the study says about 13.4% of the global fertilizer nutrient demand could be supplemented by full nutrient recovery from wastewater.
• The nutrients in wastewater could theoretically generate revenue of $13.6 billion globally: $9.0 billion from the recovery of nitrogen, $2.3 billion from phosphorus, and $2.3 billion from potassium.

The paper cites prior research showing that human urine is responsible for 80% of the nitrogen and 50% of phosphorus entering municipal wastewater treatment plants. “Removing these nutrients in time would not only be environmentally beneficial,” the paper says, “resulting in less eutrophication, it would reduce the cost of wastewater treatment while supporting closed-loop processes.”

Current wastewater nutrient recovery technologies have made significant progress. In the case of phosphorous, recovery rates range from 25% to 90%.

The paper points out that maximizing economically the potential use of thermal energy in wastewater swings on several basic requirements, including a minimum flow rate of 15 litres per second, short distances between heat source and sink, and high-performance heat pumps.

Says Vladimir Smakhtin, Director of UNU-INWEH, a global leader in research related to unconventional water sources: “Municipal wastewater was and often still is seen as filth. However, attitudes are changing with the growing recognition that enormous potential economic returns and other environmental benefits are available as we improve the recovery of the water, nutrients and energy from wastewater streams.”

Co-authors comments

“Safely managed wastewater is the key to water-related sustainable development at a time when the world is embarking on achieving SDGs, particularly SDG 6.3, which calls on us to half the proportion of untreated wastewater and substantially increase recycling and safe reuse globally by 2030.”

Praem Mehta, UNU-INWEH / McMaster University, Hamilton, Canada

“This data can be used to develop national action plans aiming at water resources management, pollution control measures, nutrient and fertilizer access, and energy recovery and energy production systems.”

Younggy Kim, McMaster University, Hamilton, Canada

“It is important to note that many innovations are available and are being refined to bridge the gap between current resource recovery levels and resource recovery potential.”

Blanca Jiménez Cisneros, UNESCO and the National Autonomous University of Mexico

“For countries to progress, there is a need to invest in a supportive regulatory and financial environment towards a green economy, and to leverage private capital for resource recovery-related business models that are financially feasible and increase cost recovery from municipal wastewater.”

Pay Drechsel, International Water Management Institute, Sri Lanka

“There is a need to facilitate and expedite implementation of resource recovery innovations particularly in low- and middle-income countries where most municipal wastewater still goes into the environment untreated. This concerns mainly the growing small and medium-size towns where agricultural land is still in proximity but also urban agricultural areas around larger cities.”

Amit Pramanik, Water Research Foundation, Alexandria, VA, USA

“The SDG challenge is on, and step-wise approaches are needed which should involve both the public and emerging private sectors which often struggle with inadequate regulatory frameworks, limited finance, and the lack of capacity to develop or evaluate bankable business plans about resource recovery and reuse. As the demands for freshwater are ever-growing and scarce water resources are increasingly stressed, ignoring the opportunities leading to safely managed wastewater is nothing less than unthinkable in the context of a circular economy.”

Oluwabusola Olaniyan, Winnipeg Water and Waste Department, Canada.

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Funding: Global Affairs Canada / Government of Canada

UNU-INWEH

The UNU Institute for Water, Environment and Health is a member of the United Nations University family of organizations. It is the UN Think Tank on Water created by the UNU Governing Council in 1996. Its mission is to help resolve pressing water challenges of concern to the UN, its Member States and their people, through knowledge-based synthesis of existing bodies of scientific discovery; cutting edge targeted research that identifies emerging policy issues; application of on-the-ground scalable solutions based on credible research; and relevant and targeted public outreach.

Related research, unconventional water sources:

Rising levels of toxic brine as desalination plants meet growing water needs

Click here: http://bit.ly/2HcOSyM

UNU-INWEH is supported by the Government of Canada through Global Affairs Canada and hosted by McMaster University.

* * * * *

Coverage highlights:

Science Magazine, USA, Reaping resources from sewers, click here

Deutschlandfunk (German national radio), Unterschätzte Ressource – Abwasser könnte künftig Energie und Nährstoffe liefern, click here

Agencia EFE, Las aguas residuales aumentarán un 51 % en 2050, pero también su aprovechamiento, click here

Europa Press, Abundante energía y nutrientes aprovechables de las aguas residuales, click here

IndoAsian News Service (India), Municipal wastewater source of valuable energy, nutrients, click here

Triple Pundit, USA, Wastewater is a Source of Valuable Water, Energy and Nutrients: How Do We Recover It?, click here

Climate News Network, UK, Wastewater flushes away a river of wealth, click here

Full coverage summary, click here

At least 140 million people in 50 countries have been drinking water containing arsenic at levels above the World Health Organization guideline

A United Nations University study compares for the first time the effectiveness and costs of many different technologies designed to remove arsenic from groundwater – a health threat to at least 140 million people in 50 countries.

Released today by UNU’s Canadian-based Institute for Water, Environment and Health, the report draws on 31 peer-reviewed, comparable research papers published between 1996 and 2018, each describing new technologies tested in laboratories and / or in field studies.

And while no single technology offers a universal solution, the research helps point to remedies likely to prove most economical and efficient given the many variables present in different locations worldwide.

Serious health, social and economic losses are caused worldwide by arsenic-contaminated water and a wide range of technologies exists to remove it but “their widespread application remains limited,” according to the report.

From 2014 to 2018, over 17,400 arsenic-related publications were published and “there is a myriad of reportedly ‘low-cost’ technologies for treating arsenic-contaminated water. But the specific costs associated with these technologies are rarely documented,” says Duminda Perera, a Senior Researcher at UNU-INWEH and report co-author.

The summary of costs and effectiveness of the few dozen arsenic remediation technologies that are directly comparable in those respects (table: http://bit.ly/2MpVWaa) can serve as a preliminary guideline for selecting the most cost-effective option, he says. It may also serve as an initial guideline (minimum standard) for summarising the results of future studies describing arsenic remediation approaches.

The report notes that “arsenic-removal technology should only be seen as efficient if it can bring the water to the WHO standard” (in 2010, WHO’s recommended a drinking water limit of 10 μg/L – micrograms per litre), but countries with resource constraints or certain environmental circumstances (e.g. typically high arsenic concentrations in groundwater) have much higher, easier-to-reach concentration targets.

“While this may help national policymakers report better results for their national arsenic reduction efforts, it may have the opposite effect on public health,” the report says. “Higher thresholds will not help solve this public health crisis. On the contrary, if a country has a feeling that the arsenic situation is coming under control, this may reduce the sense of urgency in policy circles to eradicate the problem, while the population continues to suffer from arsenic poisoning.”

“This policy approach is not well-conceived as it does not effectively resolve the issue.”

It is estimated that in Bangladesh, for example, where the nationally-acceptable arsenic limit in water is set to 50 μg/L, more than 20 million people consume water with arsenic levels even higher than the national standard.

And globally, despite international efforts, millions of people globally continue to be exposed to concentrations reaching 100 μg/L or more.

Key findings:

UNU studied 23 technologies independently tested in laboratory settings using groundwater from nine countries – Argentina, Bangladesh, Cambodia, China, Guatemala, India, Thailand, the United States, and Vietnam – and demonstrated efficiencies ranging from 50% to ~100%, with a majority reaching >90%. About half achieved the WHO standard of 10 μg/L.

14 technologies tested in the field (at the household or community level, in Argentina, Bangladesh, Chile, China, India, and Nicaragua) achieved removal efficiency levels ranging from 60% to ~99%, with 10 removing more than 90%. Only five reached established the WHO standard.

Technologies that demonstrate high removal efficiencies when treating moderately arsenic-contaminated water may not be as efficient when treating highly contaminated water. Also, the lifetime of the removal agents is a significant factor in determining their efficiency.

For lab tested technologies, the cost of treating one cubic meter (m³) of water ranged from near-zero to ~US$93, except for one technology which cost US$299 per m³. For field tested technologies, the cost of treating 1m³ of water ranged from near-zero to ~US$70.

Key factors influencing removal efficiencies and costs:

• the arsenic concentration of the influent water
• pH of the influent water
• materials used
• the energy required
• absorption capacity
• labour used
• regeneration period and
• geographical location

Remediation technologies that demonstrate high arsenic removal efficiencies in a laboratory setting need to be further assessed for their suitability for larger-scale application, considering their high production and operational costs.

Costs can be reduced by using locally available materials and natural adsorbents, which provide near zero-cost options and can have high arsenic removal efficiencies.

Leading authors Yina Shan and Praem Mehta, who worked at UNU-INWEH and are now at McMaster University, noted that exposure to arsenic can lead to severe health, social and economic consequences, including arsenicosis (e.g. muscular weakness, mild psychological effects), skin lesions and cancers (lung, liver, kidney, bladder, and skin).

Social implications of these health impacts include stigmatization, isolation, and social instability, they added. Arsenic-related health complications and mortality also lead to significant economic losses due to lost productivity. The economic burden in Bangladesh is projected to reach US$13.8 billion by around 2030.

Looking ahead, the study identifies priority areas to assist in commercializing wide-scale implementation of arsenic removal technologies.

“The main objective of the report is to help accelerate the wide-scale implementation of remediation solutions to alleviate, and ultimately eradicate, the problem of arsenic-contaminated water consumption over the next decade and meet the world’s Sustainable Development Goals,” says UNU-INWEH Director Vladimir Smakhtin.

“This report aims to inform decision-makers who face an arsenic public health challenge, of the specific costs and effectiveness of technologies tested in laboratory or field settings. It also urges researchers to present cost and effectiveness data cohesively to better inform planners’ and policymakers’ choice of the best arsenic remediation technologies.”

“Today, the current science and knowledge on arsenic remediation technologies may be mature enough to help significantly reduce the numbers of people affected by this public health problem. However, the effective translation of research evidence and laboratory-level successes into quantifiable and sustainable impacts on the ground requires a concerted and sustained effort from policymakers, engineers, healthcare providers, donors, and community leaders.”

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Authors

• Yina Shan, UNU-INWEH, McMaster University
• Praem Mehta, UNU-INWEH, McMaster University
• Duminda Perera, Senior Researcher, UNU-INWEH
• Yurissa Varela, UNU-INWEH, University of Ottawa

Background

High natural levels of inorganic arsenic exceeding the WHO limit are a characteristic feature of groundwater in many countries, including Bangladesh, India, Nepal, Mongolia, and the United States.

Most arsenic-contaminated groundwater is caused naturally, some is caused by industry – mining, fertilizers / pesticides, waste disposal, and manufacturing.

In nature, the poison can be released from arsenic-rich rocks by high acidity (pH) in oxygen-rich groundwater. Arsenic contamination is also mobilized by human interventions, such as.

Globally, the primary route of human exposure to arsenic is contaminated drinking water; some is the result of irrigating crops with contaminated water.

Sustainable Development Goal 3 (“good health and wellbeing”), adopted by UN Member States in 2015 for achievement by 2030, recognized the need to remove hazardous chemicals, including arsenic, from the world’s ecosystems. SDG 3.9 aims to “substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water, and soil pollution and contamination.” And SDG 6 (“Clean water and sanitation”) includes target 6.3, calling for an “improvement to water quality by reducing pollution, eliminating dumping and minimizing the release of hazardous chemicals and materials” (https://sustainabledevelopment.un.org).

UNU-INWEH

http://bit.ly/1vjfKAS

The UNU Institute for Water, Environment and Health is a member of the United Nations University family of organizations. It is the UN Think Tank on Water created by the UNU Governing Council in 1996. Its mission is to help resolve pressing water challenges of concern to the UN, its Member States and their people, through knowledge- based synthesis of existing bodies of scientific discovery; cutting edge targeted research that identifies emerging policy issues; application of on-the-ground scalable solutions based on credible research; and relevant and targeted public outreach.

UNU-INWEH is hosted by the Government of Canada and McMaster University

Coverage highlights:

Full coverage summary, click here

News release in full, click here.

World’s ~16,000 desalination plants discharge 142 million cubic meters of brine daily — 50 percent more than previously estimated; Enough in a year to cover Florida under a foot (30.5 cm) of brine

The fast-rising number of desalination plants worldwide — now almost 16,000, with capacity concentrated in the Middle East and North Africa — quench a growing thirst for freshwater but create a salty dilemma as well: how to deal with all the chemical-laden leftover brine.

In a UN-backed paper, experts estimate the freshwater output capacity of desalination plants at 95 million cubic meters per day — equal to almost half the average flow over Niagara Falls.

For every litre of freshwater output, however, desalination plants produce on average 1.5 litres of brine (though values vary dramatically, depending on the feedwater salinity and desalination technology used, and local conditions). Globally, plants now discharge 142 million cubic meters of hypersaline brine every day (a 50% increase on previous assessments).

That’s enough in a year (51.8 billion cubic meters) to cover Florida under 30.5 cm (1 foot) of brine.

The authors, from UN University’s Canadian-based Institute for Water, Environment and Health, Wageningen University, The Netherlands, and the Gwangju Institute of Science and Technology, Republic of Korea, analyzed a newly-updated dataset — the most complete ever compiled — to revise the world’s badly outdated statistics on desalination plants.

And they call for improved brine management strategies to meet a fast-growing challenge, noting predictions of a dramatic rise in the number of desalination plants, and hence the volume of brine produced, worldwide.

(Note: The authors use the term “brine” to refer to all concentrate discharged from desalination plants, as the vast majority of concentrate (>95%) originates from seawater and highly brackish groundwater sources.)

The paper found that 55% of global brine is produced in just four countries: Saudi Arabia (22%), UAE (20.2%), Kuwait (6.6%) and Qatar (5.8%). Middle Eastern plants, which largely operate using seawater and thermal desalination technologies, typically produce four times as much brine per cubic meter of clean water as plants where river water membrane processes dominate, such as in the US.

The paper says brine disposal methods are largely dictated by geography but traditionally include direct discharge into oceans, surface water or sewers, deep well injection and brine evaporation ponds.

Desalination plants near the ocean (almost 80% of brine is produced within 10km of a coastline) most often discharge untreated waste brine directly back into the marine environment.

The authors cite major risks to ocean life and marine ecosystems posed by brine greatly raising the salinity of the receiving seawater, and by polluting the oceans with toxic chemicals used as anti-scalants and anti-foulants in the desalination process (copper and chlorine are of major concern).

“Brine underflows deplete dissolved oxygen in the receiving waters,” says lead author Edward Jones, who worked at UNU-INWEH, and is now at Wageningen University, The Netherlands. “High salinity and reduced dissolved oxygen levels can have profound impacts on benthic organisms, which can translate into ecological effects observable throughout the food chain.”

Meanwhile, the paper highlights economic opportunities to use brine in aquaculture, to irrigate salt tolerant species, to generate electricity, and by recovering the salt and metals contained in brine — including magnesium, gypsum, sodium chloride, calcium, potassium, chlorine, bromine and lithium.

With better technology, a large number of metals and salts in desalination plant effluent could be mined. These include sodium, magnesium, calcium, potassium, bromine, boron, strontium, lithium, rubidium and uranium, all used by industry, in products, and in agriculture. The needed technologies are immature, however; recovery of these resources is economically uncompetitive today.

“There is a need to translate such research and convert an environmental problem into an economic opportunity,” says author Dr. Manzoor Qadir, Assistant Director of UNU-INWEH. “This is particularly important in countries producing large volumes of brine with relatively low efficiencies, such as Saudi Arabia, UAE, Kuwait and Qatar.”

“Using saline drainage water offers potential commercial, social and environmental gains. Reject brine has been used for aquaculture, with increases in fish biomass of 300% achieved. It has also been successfully used to cultivate the dietary supplement Spirulina, and to irrigate forage shrubs and crops (although this latter use can cause progressive land salinization).”

“Around 1.5 to 2 billion people currently live in areas of physical water scarcity, where water resources are insufficient to meet water demands, at least during part of the year. Around half a billion people experience water scarcity year round,” says Dr. Vladimir Smakhtin, a co-author of the paper and the Director of UNU-INWEH, whose institute is actively pursuing research related to a variety of unconventional water sources.

“There is an urgent need to make desalination technologies more affordable and extend them to low-income and lower-middle income countries. At the same time, though, we have to address potentially severe downsides of desalination — the harm of brine and chemical pollution to the marine environment and human health.”

“The good news is that efforts have been made in recent years and, with continuing technology refinement and improving economic affordability, we see a positive and promising outlook.”

Background

The growth of desalination

Starting from a few, mostly Middle Eastern facilities in the 1960s, today 15,906 operational desalination plants are found in 177 countries. Two-thirds of such plants are in high-income countries.

The process is becoming more affordable, the paper says, attributable to falling costs due to continued improvements in membrane technologies, energy recovery systems, and the coupling of desalination plants with renewable energy sources.

Brine management can represent up to 33% of a plant’s cost and ranks among the biggest constraints to more widespread development.

Almost half of the global desalination capacity is located in the Middle East and North Africa region (48%), with Saudi Arabia (15.5%), the United Arab Emirates (10.1%) and Kuwait (3.7%) being both the major producers in the region and globally.

East Asia and Pacific and North America regions produce 18.4% and 11.9% of the global desalinated water, primarily due to large capacities in China (7.5%) and the USA (11.2%) respectively.

The widespread use of desalination in Spain (5.7%) accounts for over half of the total desalination in Western Europe (9.2%). The global share in desalination capacity is lower for Southern Asia (3.1%), Eastern Europe and Central Asia (2.4%) and Sub-Saharan Africa (1.9%), where desalination is primarily restricted to small facilities for private and industrial applications.

Desalination is an essential technology in the Middle East and for small island nations which typically lack renewable water resources.

Eight countries — the Maldives, Singapore, Qatar, Malta, Antigua and Barbuda, Kuwait, The Bahamas and Bahrain – can meet all of their water needs through desalination. Six others can meet over 50% of their water withdrawals through desalination: Equatorial Guinea, UAE, Seychelles, Cape Verde, Oman and Barbados.

Almost 22 million m3/day of brine is produced at a distance of greater than 50km from the nearest coastline. Despite the large volume of brine produced in these areas, very few economically viable and environmentally sound brine management options exist. Brine produced inland poses an important problem for many countries located in all world regions, with 64 countries producing more than 10,000 m3/day of brine in inland locations.

Inland brine production is a particular issue in China (3.82 million m3/day), USA (2.42 million m3/day) and Spain (1.01 million m3/day).

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Authors

Edward Jones1,2, Manzoor Qadir1, Michelle T.H. van Vliet2, Vladimir Smakhtin1, Seong-mu Kang1,3

1 UN University Institute for Water, Environment and Health (UNU-INWEH), Canada

2 Water Systems and Global Change, Wageningen University, The Netherlands

3 Gwangju Institute of Science and Technology (GIST), Republic of Korea

UNU-INWEH

http://bit.ly/1vjfKAS

The UNU Institute for Water, Environment and Health is a member of the United Nations University family of organizations. It is the UN Think Tank on Water created by the UNU Governing Council in 1996. Its mission is to help resolve pressing water challenges of concern to the UN, its Member States and their people, through knowledge- based synthesis of existing bodies of scientific discovery; cutting edge targeted research that identifies emerging policy issues; application of on-the-ground scalable solutions based on credible research; and relevant and targeted public outreach.

UNU-INWEH is hosted by the Government of Canada and McMaster University.

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Coverage summary presentation, click here

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Newswires

The Associated Press, US (via the Daily Mail, UK), Too Much Brine? Study Highlights Growing Toxic Brine Problem, click here

Reuters, UK, Too much salt: water desalination plants harm environment – UN, click here

Spanish, Alrededor de 16.000 plantas desalinizadoras están dañando el medio ambiente según ONU, click here

Portuguese: Sal em excesso: unidades de dessalinização de água prejudicam o meio ambiente, diz ONU, click here 

Arabic: الأمم المتحدة: محطات تحلية المياه تضر بالبيئة بسبب المخلفات شديدة الملوحة , click here

Agence France Presse, France, Desalination produces more toxic waste than clean water, click here

French: A la sortie des usines de désalinisation, plus de rejets toxiques que d’eau, click here 

Japanese: 海水淡水化、真水上回る量の有毒物質発生 「酸欠海域」形成の恐れも, click here
Chinese: 海水淡化產生有毒物 研究：遠多於提煉淡水, click here

2nd story: Fixing the environment: when solutions become problems, click here

French: Restaurer l’environnement: quand les solutions deviennent problèmes, click here

EFE, Spain, Spanish: Estudio advierte sobre la amenaza medioambiental de plantas desalinizadoras, click here

Portuguese: Estudo adverte para ameaça ambiental de usinas de dessalinização de água, click here

Bloomberg, USA

Saudi Arabia’s thirst for water is creating a toxic brine problem, click here

Spanish: Apaciguar la sed en Arabia Saudita tiene un costo demasiado alto, click here

Portuguese: Água dessalinizada agrava poluição no Oriente Médio e África, click here

Deutsche Presse Agentur, Germany, (via Die Welt) UN warnt vor giftigen Rückständen bei Meerwasserentsalzung, click here

Australian Associated Press, Australia, The world’s growing toxic brine problem, click here

IndoAsian News Service, India, Desalination plants creating salty dilemma, globally: UN, click here

SciDev, UK, Leftover brine threatens future desalination, click here

InterPress Service, Italy: A Salty Dilemma, click here;  

op-ed:  Quenching Humanity’s Freshwater Thirst Creates a Salty Threat, click here

http://www.ipsnews.net/2019/01/quenching-humanitys-freshwater-thirst-creates-salty-threat/

News sites

UK

BBC Online, UK, Concerns over increase in toxic brine from desalination plants, click here

BBC World Service Radio, UK “A UN-backed paper has warned about the impact on marine life of pumping into the sea a chemical-laden brine which is a by-product from desalination plants that make salty seawater drinkable. Manzoor Qadir is one of the paper’s authors, and explains its findings.” (3 mins, 20 sec long, begins at 15 min, 22 sec) click here

New York Times (Oct. 22, 2019) The World Can Make More Water From the Sea, but at What Cost?, click here

National Geographic, Desalination plants produce more waste brine than thought, click here

Italian: I desalinatori producono più salamoia di quanto si pensava, click here

Gizmodo, The Dirty Truth About Turning Seawater Into Drinking Water, click here 

Wired, Desalination Is Booming. But What About All That Toxic Brine?, click here

Science News, Desalination pours more toxic brine into the ocean than previously thought, click here

Inside Science, Making Salty Water Drinkable Also Makes Brine, click here

France

Le Monde: Dessalement de l’eau : l’ONU alerte sur les quantités de saumure déversées, click here

Le Figaro: La dessalinisation de l’eau de mer crée trop de pollution, click here

Science et Avenir: A la sortie des usines de désalinisation, plus de rejets toxiques que d’eau, click here

Orange actu, A la sortie des usines de désalinisation, plus de rejets toxiques que d’eau, click here 

Journal de l’environnement, Les usines de désalinisation polluent plus que prévu click here

Spain

El País, Las desaladoras generan tanta salmuera como para cubrir España, click here

ABC: Las desalinadoras expulsan al mar el doble de salmuera del que se creía, click here

Germany / Austria 

Deutschlandfunk,, Sole-Rückstände viel größer als gedacht, click here

WirtschaftsWoche Online, UN warnt: Giftigen Rückständen bei Meerwasserentsalzung, click here

Science.ORF, Entsalzungsanlagen erzeugen Umweltgifte, click here

Belgium

VRT News, VN-rapport: steeds meer pekel in zee door ontziltingsinstallaties, click here

Grenzecho, UN warnt vor giftigen Rückständen bei Meerwasserentsalzung, click here

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Haaretz, Israel, World Desalination Industry Is Dumping 50% More Toxic Brine Than Thought, click here

Engineering News, South Africa, UN warns of rising levels of toxic brine as more desalination plants are built, click here

Coverage summary, click here

News release in full, click here