The vicious cycle of water supply

Alex writes*

Athens, Greece’s capital and largest city, has a population of 3,2 million. The city attracts around 6 million tourists each year, many seeking sunny weather. But high temperatures also represent a threat — to the city’s water supply.

Droughts, wildfires (Η Καθημερινη 2023) and heatwaves (euronews.2022) are not surprising news anymore, so what happens if Athens lacks the  water to extinguish the fires, irrigate crops, or serve the population?

These goals are already difficult to achieve, but current water management makes water scarcity worse.

Athens’s water quality is among the best in Europe (scoring 10 in the EU’s Urban Water Atlas), but its management of supply and environmental flows in the Mornos and Evinos rivers is lacking, in what Giorgos Kallis calls a “vicious cycle of water resources.

Athenians have discussed water scarcity and management since the nineteenth century. One choice that altered Greece’s water infrastructure was the construction of a dam on the Mornos River, which not only failed to meet skyrocketing demand but pushed demand even further. That was because the Athens Water Supply and Sewerage Company (EYDAP) kept prices low to encourage consumption. Citizens bought dishwashers, took longer showers, and used water in many novel ways.

The 2004 Olympic Games boosted the city’s development and its water network, further increasing demand. According to the EEA, Athens is growing at an excessive rate of 6% per year. Supply, on the other hand, is falling. Precipitation and river flow are projected to decrease by 7-12% (against mean flow levels) over the 30-year period to 2040. Supply may not be sufficient, and “supply-oriented” solutions are expensive, unsustainable, and inadequate if demand is not managed.

Bottom Line: It is important understand the root causes of water scarcity in Athens and to break this vicious cycle of water supply by concentrating on more sustainable and equitable water management practices.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

The dry realities facing Lyon

Elise writes*

The Minister of the Ecological Transition declared that “France is in a state of alert” in relation to the unprecedented drought that began in January 2023. The country has experienced 32 days without rain, and there are no signs of rain on the horizon.

Why is this concerning? Serge Zaka, a professor of agroclimatology notes that there have been dry February’s in the past, but this episode is significant because it is part of a 15-month pattern of deficient precipitation. Surface waters are limited, and groundwater is not recharging. Lyon, for example, has more groundwater discharge than recharge.

What are the reactions?

The government has created a Committee of Drought Anticipation. Those who remember the dry summer of 2022 worry about this coming summer. Lyon faced “red crisis” restrictions in the summer of 2022.

The region around Lyon, 2021 (left) vs 2022 (right)

Farmers are concerned, as they have little water to irrigate their crops. Many have protested, claiming that they should have priority access to water. Lyon’s wine sector is worried about lower production and fewer tourists. Ski stations worry about a lack of snow.

Is this linked to climate change? Yes, because human activity has led to the perturbation of the water cycle, where longer periods of droughts followed by heavy rainfall are expected. In the case of this 32-day drought, an anticyclone that is hovering around Europe has reduced rainfall. By 2050, it is expected that the Rhone and Saone River flowing through Lyon will carry 20-50 percent less water.

What about rain? Even if it started raining heavily, it would not give enough time for the groundwater to recharge before summer. At best, it would increase surface water reserves that could be used in place of groundwater.

So what are the solutions? Experts recommend a complete reform of how we think about water as these unprecedented events become the new normal. In Lyon, a green party succeeded in replacing ‘Eau du Grand Lyon’ (a subsidiary of for-profit Veolia) that was managing water services with public management. The Greens argued that water, as a common good, should be managed by citizens. Other solutions include reforming agriculture to be more resilient, acting on weak linkages in the system, revaluing wastewater and encouraging sobriety on all levels.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Lake Wyangan’s toxic secret

Flóra writes*

At first sight, Griffith seems like a regular rural town in the Murrumbidgee Irrigation Area of Australia. In recent years, however, a potential link has been discovered between a fatal disease and a lake in this town, namely between Motor Neuron Disease (MND) and Lake Wyangan.

MND is a progressive neurological disorder that slowly takes away people’s ability to walk, speak, swallow and finally breathe. According to Health Direct, people diagnosed with MND usually live another 2-3 years. MND is caused by a genetic condition or a combination of environmental, lifestyle and genetic factors. The number of non-genetic cases in Australia has  increased by 250% in the last 25 years, but the situation is worst in New South Wales’s agricultural area, Riverina, which includes the towns of Griffith and Wagga Wagga, where rates of MND are 7 times the national average (The Guardian) .

What might be causing these abnormally high numbers? Scientists blame the blue-green algae in Lake Wyangan, which is close to Griffith and surrounded by farms. It is a terminal, dual-basin lake that receives inflows from natural drainage, irrigation return flows, local stormwater and, supplementary “top ups” that arrive via irrigation infrastructure.

SBS News and Griffith City Council claim that blue-green algae results from a combination of drought, calm weather conditions and irrigation return flows. These algal blooms affect aquatic life, block water pumps and can make water undrinkable.

NB: “Blue-green algae” is a misleading name, since it refers to a cyanobacterium that produces a neurotoxin called BMAA. The fact that algal toxins can be colourless and odourless as well as persisting for weeks after an algal bloom makes it hard to avoid BMAA.

A study published in 2020 found that the ingestion of BMAA causes nerve damage similar to that observed in the early stages of MND. Although there is not yet enough evidence to prove blue-green algae causes MND, the connection deserves attention. According to The Guardian, the NSW government does not want to fund research, since a causal link could lead to legal liabilities for the government.

Despite all these challenges, the Griffith City Council has ambitious plans to improve water quality in the lake and sustainably supply water to Riverina’s irrigators. The plans focus on reducing salinity and managing nutrient levels to reduce algal blooms as well as connecting the two basins so that a flow-through system improves irrigation water quality.

The future will determine if those plans are effective.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Oaxaca: Indigenous changemakers

Elisa writes*

Oaxaca is a state of southern Mexico filled with culture, biodiversity — and  water scarcity. Oftentimes, water management is associated with a board of old, rich people sitting at meetings discussing theoretical economic “solutions”, failing to address systemic issues as it is not in their interest to do so. However, within the Copalita-Zimatán-Huatulco watershed, which encompasses Oaxaca, Indigenous people and local residents are taking the initiative (Medium.com, 2022). Pollution, overconsumption, and poor management limit water availability, so residents get water from wells or private water trucks known as pipas (Starkman, 2013). Federal and municipal organizations have tried to improve water quality, but tap water is not drinkable, forcing residents to find their own solutions (Mansourian et al., 2020).

Oaxaca has 19 ethnic groups speaking 16 languages (globalsiasar.org, 2017). This diversity often results in indigenous communities dealing with government failures. Indigenous people have built 579 water infrastructure projects. Local families work with municipalities to construct water pans, wells, and dams (Pelliccia, 2022). The farming cooperative Alternativa Agricultura Zapotec has increased Milpa production, constructed livestock enclosures and compost systems, and captured rainwater for irrigation (Alistair, 2018). These projects improve water security for residents but also set an example — inspiring others to help with water scarcity.

It appears that local initiatives have been significantly more successful than governmental efforts. One reason may be cultural. Indigenous communities such as the Zapotec, for example, protect nature against human disturbance.

Bottom Line: Indigenous-led, community-based initiatives are more effective than centralized, federal efforts in addressing water scarcity.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Hong Kong has a water crisis?

Jasmine writes*

Unseen by its 8 million residents, a water crisis is approaching Hong Kong. Seventy to eighty percent of Hong Kong’s water comes from the Dongjiang river, which also brings water to Macau and other regions in the Pearl River Delta. The Dongjiang river is reaching its “critical limit” and further growth in the region might exceed that limit.

Things only become worse for Hong Kong when considering that the city-state lost 32.5% of its water to leakage and theft. Compare that figure to Tokyo, which dropped its leakage from 20% in 1955 to 2% today.

Hong Kong needs to focus on water loss management to reduce its risks. The Total Water Management (TWM) Strategy was launched in 2008, and it reduced leakage to 15% by 2019. TWM is also trying to get Hong Kong residents to use less water.

I grew up in Hong Kong and never considered that the city was facing a water crisis. I don’t think I use absurd amounts of water, but I also paid little attention to my usage. A study conducted by the OECD across 48 major cities reported that Hong Kong residents have very high domestic water per capita. Hong Kong’s illusion of unlimited water has encouraged residents to overconsume this scarce resource. The TWM strategy [pdf] promotes water-saving devices and conservation awareness in schools, but Hong Kong is consuming more water than ever.

Hong Kong’s water crisis will only worsen unless stricter policies are implemented and additional action is taken.

Bottom Line: Hong Kong’s heavy reliance on the Dongjiang river, leaky pipes, and overconsumption of water risks exposing the city to severe water scarcity in the near future.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

The politics of Dublin’s water scarcity

Aoibheann writes*

How can a city with lots of water have a water scarcity problem?

Look no further than Dublin.

Ireland has 10,600 m3 of renewable freshwater resources per inhabitant (Eurostat, 2022), and Dublin city gets around 1000mm of precipitation annually (Worldbank, 2021). According to Irish Water in 2015 [pdf], existing water sources supplied 623 megalitres/day (Mld) to Dublin, against average demand of 540 Mld, which works out to 375 litres per day per meter (CSO, 2021).

Several factors contribute to Dublin’s water scarcity, including the city’s Victorian-era infrastructure, rapid growth, history of “managing” scarcity by increasing supply, and climate change (Kelly-Quinn et al., 2014).

But the most striking factor is a lack of domestic water charges. Ireland is the only OECD country without direct water charges; water services are funded by general taxation (OECD, 2018) [pdf]. Ireland’s lack of domestic water charges exacerbates Dublin’s water scarcity problems. Missing prices complicate efforts to reduce demand, increase the need for supply-side solutions, and hamper Irish Water’s efforts to pay water service costs (Zhao & Crosbie, 2012). The absence of water charges is particularly ironic when one considers that the “Dublin principles” say “water has an economic value in all its competing uses and should be recognized as an economic good” (ICWE, 1992) [pdf].

Why does Dublin lack domestic water charges? Politics, and more particularly the Irish government’s botched attempt at introducing water pricing in 2014.

Numerous factors contribute to the politicisation of water. “Framing” — or the conceptualisation of an issue — has a significant role (Chong & Druckman, 2007). A frame narrows the focus to an issue’s implications for a particular set of values. Different frames can oppose each other, and the  government lost the framing contest quite spectacularly.

Protests took place in towns and cities across the Republic, including Letterkenny in County Donegal, where more than 8,000 people are believed to have taken to the streets — BBC – KEIRON TOURISH

In the context of severe austerity measures and the rolling back of the Irish welfare state, the government framed the need for domestic water charges as a means of boosting economic efficiency (O’Neill et al., 2018). The opposition, on the other hand, framed charges as part of the government’s anti-poor agenda. The opposition’s framing was particularly potent in the context of the financial crisis in which public services were slashed and widespread government corruption was exposed.

The government’s misguided framing, combined with low public trust, meant that the public was unlikely to support its water management reform.

Bottom Line: Irish politics have impeded the adoption of domestic water charges, which are deemed integral to integrated water resources management. A key issue has been the government’s inability to frame water charges as useful to the public. The government should try to re-frame the issue in terms of environmental or pro-poor outcomes, if it wants to shift public sentiment.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Will Las Vegas disappear?

Elena writes*

Las Vegas, USA is located in the Mojave desert and home to 650,000 people. The city is constantly facing water scarcity, which is worsened by climate change. For example, temperatures are more extreme and the water cycle is accelerating.

In 2012, the Scripps Institution of Oceanography declared a 50% likelihood of Lake Mead — the reservoir and water source next to Las Vegas — going (functionally) dry by 2021 if nothing was done to reduce water use. In 2022, Mead reached an historically low level due to droughts and overallocation.

Mead is not yet dry, but the city needs to reduce demand. An average household consumes around 0,83 m3 of water daily (220 gallons/HH). This number is high, but it’s better than before. Brelsford and Abbott report that water consumption per capita declined by 55% between 1996 and 2007, while population increased 63%. This fall in per capita use is attributed to water-efficient appliances in new houses, smaller lots (thus landscaping),  and conservation policies (raising prices and fines) attempting to change people’s behaviour.

Bottom Line: Las Vegas tries to limit its water demand, but its dependence on an unsustainable source and vulnerability to climate change puts its future survival at risk.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Pollution in Delhi’s Yamuna

Shreya writes*

The River Yamuna is one of India’s two holy rivers, flowing through five states before it joins the Ganga at Prayagraj — formerly Allahabad (Bhattacharyya & Prasad 2020). However, the Indian capital of New Delhi can hardly worship its stretch of the river – rather, it is frequently called a ‘dirty drain’ (Singh 2011). Dumping waste into the river is an entrenched public attitude in Delhi – meanwhile, government efforts to change such attitudes and improve water management infrastructure have been minimal at best, and careless at worst. This neglect has severely degraded Delhi’s only local source of water, forcing it to rely on external water sources and thus gravely endangering its water security (Economic Survey of Delhi, 2018-19).

Unregulated industrial and domestic pollution in Delhi alone contribute a whopping 79% of the Yamuna’s entire pollution load (Upadhyay et al. 2011). Firdaus & Ahmad (2012) calculate that 85% of this pollution comes from domestic sources. Unprecedented population growth has led to the growth of unauthorised housing colonies without sewage connections that dump waste directly into the river. Secondly, open defecation in these unauthorised colonies contributes organic and pathogenic contaminants to the river. Industries and unauthorised dairy farms with inefficient water treatment systems also discharge untreated effluents, cattle dung and liquid waste into the river (Firdaus & Ahmad 2012).

All this has severely degraded water quality in the river, dissolved oxygen content is approaching 0 mg/L, and biological oxygen demand was highest in Delhi at 18 mg/L in 2005 (Upadhyay et al. 2011). In response to public worries, the Government of India launched the first phase of the Yamuna Action Plan in 1993, with its second phase beginning in 2004 (Sharma and Kansal [pdf]). The plans aimed to increase the capacity of sewage treatment plants (STPs) and sewer connections, construct public toilets, develop the riverfront and increase public awareness and participation about the problems facing the Yamuna (Sharma and Kansal [pdf]). However, both plans, despite a hefty investment of Rs. 2700 crore [€ 31 million], failed completely in Delhi (The Pioneer 2016).

According to Singh (2011), one reason for failure was a lack of funding from state governments – a glaring example of the corruption that frequently plagues the water sector. Additionally, sewage treatment plants (STPs) were underutilised because they were built in areas that did not produce much sewage. Meanwhile, areas that produced more sewage were underserviced and forced to deposit waste directly into the river (Upadhyay et al. 2011). STPs were also poorly designed and maintained, suffering from frequent electrical breakdowns and understaffing (Parween et al. 2017).  Moreover, Delhi’s sewage demand was heavily underestimated, such that STPs could treat only 40% of the city’s generated sewage (Upadhyay et al. 2011). Lastly, STPs did not address non-point sources of pollution, and did not disinfect water to remove bacteria like coliform, leaving ‘treated’ water highly polluted (Sharma and Kansal [pdf]).

Similarly, the public toilets were absent in areas of high population density, and underutilized where constructed (Singh 2011).  Accessibility was also largely overlooked – floor-level pits were difficult for elderly and disabled people to use, while the Rs. 2 [EUR 0.02] fee per visit was too expensive for many poor users (The Pioneer 2016). Thus, the wastes previously produced continued polluting the river, as the infrastructure was inefficiently designed or inaccurately allocated.

Sharma and Kansal [pdf] show that the effects of these oversights by the government worsened pollution in the Yamuna – dissolved oxygen values remained below 5 mg/L and bacterial contamination was too high to comply with environmental standards. Additionally, the plan intended to make the Yamuna water safe for bathing (Class B) by the Central Pollution Control Board standards, but water quality remains at Class D.

Continued pollution and inefficient governance have thus rendered Delhi’s Yamuna completely unusable, despite it being one of the city’s key water sources. Delhi now gets around 50% of its drinking water from neighbouring states – an uneasy and unsustainable solution to its water woes (Economic Survey of Delhi, 2018-19).

Bottom Line: The case of Delhi’s Yamuna shows how corruption and government oversight in water management can perpetuate public attitudes that support pollution, degrading crucial water sources and endangering water security.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

Cape Town’s returning challenge

Bente writes*

How do we stop a “day zero” of running out of water? Cape Town was one of the first cities facing this problem. How did it escape — and can it do it again?

Day Zero is reached when Cape Town’s dam levels fall below 13,5% (Climate Portal, 2022). During the severe drought of 2015-2018, dam levels were under 21%, and taps were on the verge of going dry (memeburn, 2018). Farmers helped by giving their water to the city. The government added restrictions to water use, increased water tariffs for heavy water users, and reconfigured its pressure management system — saving around 10% of supply (Global Resilience Institute, Bloomberg, 2019). The return of rain also helped, but these actions and results may not be easy for the next drought hitting Cape Town or another city.

Image Source

So which measures should always be taken to avoid a day zero? The answer may be by trying to change the water usage habits of citizens. How did Cape Town change this successfully? They started by making things such as filling pools, water gardens, washing cars, or other non-essential uses illegal (National Geographic, 2018). Restaurants asked people to minimize toilet flushing with the slogan “if it’s yellow, let it mellow” (World Economic Forum, 2019). But maybe the most important measures were the social controls that the city implemented. This started with weekly updates of the dam levels to create awareness of water scarcity and digital boards on highways that counted down to Day Zero. In 2018, the city published a city-wide water map showing household level water usage, which helped people hold each other accountable (Bloomberg, 2019). An online community shared tips for saving water.

Do social norms work in long term? Demand is increasing again because social measures only worked when the drought was severe. When supplies returned, so did demand. It is necessary to “destroy” demand if the city wants to avoid a future day zero, by encouraging people to permanently reduce their demand for water.

Bottom Line: Cape Town implemented restrictions to avoid Day Zero once; if it wants to avoid a future day zero, then it needs to destroy demand.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂

The endless issue: water pollution

Mira writes*

Costa Rica is proud of its sustainability, but it’s mismanaging its water. As the head of the Institute of Aqueducts and Sewers (AyA) said in 2019:  “We sell ourselves as a green country, but in terms of wastewater and the quality of our rivers we have not been consistent”. In the country, low water quality, and subsequently high levels of pollution has negatively impacted the lives of many.

Specifically in urban areas, this water pollution can directly be seen in rivers. According to La Nacion, San Jose’s levels of water pollution are continuously increasing as untreated wastewater is diverted into rivers rather than into sanitary sewer systems. Rivers also suffer from trash dumping. In a further article the minister of health commented on the threat this posed to a “potential harmful disease outbreak”. In a 2013 research paper on “water supply and sanitation,” Bower found linked high levels of water pollution to untreated urban and rural wastewater. Pollution was worse near hospitals. The release of chemicals, antibiotics etc. into the water supply threatens ecosystems and people.

A 2021 study of water quality in Cartago (an agricultural region close to San Jose) found high levels of pollutants and chemicals in the water. Pollution was linked to urban population, erosion and agriculture — specifically from unauthorized pesticides.

Overall the agricultural sector is a large contributor to water pollution. Agriculture affects water quality through fertilizers, which in recent years have only increased in concentration. Simultaneously, contamination through organic matter from livestock farming. Both integrating into the water system as ground water, run off water and through irrigation.

What is being done? Agua Tica is promoting [pdf] good agricultural practices (GAPs). In the past much produce has been grown with the help of agrochemicals and other synthetic fertilizers, with the intention of increasing crop yields. Agua Tica trains farmers on implementing sustainable farming practices at a low cost. Many farmers have implemented GAPs as they wanted to protect their environment and people from pesticides.

The Los Tajos wastewater-treatment plant, opened in 2015, has increased wastewater treatment capacity. The AyA is working to expand and repair sewer infrastructure around the capitol.

Bottom Line: Costa Rica’s poor management of water has led to high water pollution mainly caused by the urban population, agriculture and industry. To resolve this crisis farmers are being trained and the sewage system is being expanded.


* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂