Estonians consume 88 liters of water per day on average. The EU average is 144 liters per day, so at least we can’t be directly accused of wasting water. But knowing that only 10% of Estonia’s lakes are in good condition and all coastal water bodies are in poor or very poor condition, that Estonians eat about three times more meat than nutritionists recommend, and throw away about 60 kg of food and 12 kg of clothing per person annually, our invisible water consumption is enormous – and so is our environmental impact.

In addition to water use directly from the tap and through our dietary and consumption habits, we also need to consider where water goes after use. It doesn’t just go away – there is no such place as “away".

Water in the city: Where does the runoff go, if not away?

“An estimated 1,800 tons of pharmaceutical residues end up in the Baltic Sea every year. Pharmaceutical residues in wastewater promote the development of bacteria resistant to antimicrobial agents, which the World Health Organization (WHO) considers one of the greatest global health threats. Pollutants cause reproductive disorders and hormonal changes in fish, threatening our fish stocks and returning to humans through the food chain,” explains the Ministry of Climate’s website. Pollutants in nature are everyone’s problem.

In Tallinn, wastewater goes to Paljassaare, and the goal of the water treatment plant is to discharge water into the sea as clean as the surface water taken from Lake Ülemiste for our tap water.

According to Professor Sergei Preis, head of the Environmental Technology Laboratory, one of the biggest problems is pharmaceutical residues in municipal wastewater. “During biological treatment, these residues are not oxidized, which affects not only the microorganisms in treatment plants but also those in nature – rivers, lakes, seas, and oceans,” he explains. This means that once medicines reach rivers, lakes, or the sea, they can persist indefinitely, eventually entering the tissues of living organisms. “Such infiltration affects organisms according to the drug’s purpose – whether neuroleptics, hormones, anticonvulsants, laxatives, or anti-inflammatory drugs. Even in small quantities, drugs have a significant effect, altering fish and mollusk behavior, reproduction, development, and resistance to infections – usually negatively from the perspective of animal populations,” Preis elaborates.

Few medicines are fully metabolized in the human body, and even metabolites often revert to their original pharmaceutical form under environmental conditions. Thus, nearly all medications are pollutants, and wastewater from medical institutions is particularly dangerous – hospitals use drugs rarely found in households.

Preis gives some examples: the synthetic female hormone analogue ethinylestradiol alters the sex of adult fish from male to female in just a week at concentrations as low as 0.1 nanograms per liter. The Baltic Sea has, at times, shown concentrations 170 times higher. Microorganisms develop resistance to antibiotics, and we cannot guarantee that disease-causing agents won’t arise in nature that are untreatable with conventional antibiotics. Some drugs accumulate in fish fat tissue and make their way back onto our plates.

Water in nature: pollution, scarcity, and conflicts increase

Generally, Estonia doesn’t suffer from water scarcity because annual precipitation exceeds evaporation, allowing surplus water to feed both surface and groundwater reserves. Major water level drops are associated with mining or densely populated areas.

According to Joonas Pärn, a hydrogeologist at the Estonian Geological Survey, shallow groundwater quality issues are often region-specific, with the most widespread impact coming from agricultural pollutants (e.g., nitrates, pesticide residues). Mines (especially oil shale mining and industry in Ida-Viru County) and unsewered areas, where household wastewater can seep into the ground (causing microbiological pollution and sometimes increased ammonium and nitrate levels), also have localized impacts. The quality of spring water often depends on land use in the catchment area. Pärn gives an example: a seemingly clear spring in the middle of farmland may contain nitrate levels exceeding the legal limit for drinking water (50 mg/L), whereas a similar spring in a forest or pasture area might be safer to drink from.

Deeper pressurized groundwater layers are better protected from pollution due to confining layers above them, making them “cleaner” from human impact. However, this doesn’t mean such water doesn’t contain substances exceeding drinking water limits. For instance, deep groundwater in Estonia often contains high levels of iron due to natural processes in oxygen-poor environments; even deeper, water may contain excessive chlorine from its marine origin.

Pärn points out two key concerns about groundwater: in agricultural regions, shallow wells are contaminated by farming chemicals, and well water is polluted due to inadequate wastewater treatment. He notes that the intensification of agriculture and animal husbandry in some areas of Estonia has increased shallow groundwater nitrate levels to those last seen in the Soviet era. “It’s a complex issue with no simple solution,” says Pärn. “To keep Estonian agriculture economically competitive, production costs must stay low, which makes intensive farming attractive. But at the same time, the risk of groundwater pollution and surface water eutrophication rises. The key likely lies in closer cooperation among the agricultural sector, scientists, and authorities overseeing water use and protection,” he explains.

In 2023, only 51% of Estonia’s 744 surface water bodies were rated as being in “good” condition; none were in “very good” condition. 60% of rivers and only 10% of lakes were in good condition, while all coastal water bodies were in poor or very poor condition. Tallinn University ecohydrology professor Jaanus Terasmaa presented the state of inland waters in April last year at an Estonian Academy of Sciences seminar. While Professor Preis described the consequences of pollutants entering nature, Terasmaa added that current monitoring methods don’t reflect the actual pollution situation, as they track a limited number of outdated pollutants and ignore the combined effects of multiple chemicals on the aquatic environment.

In addition to pollution, climate change is having broader impacts on water systems. A concrete example: the spring flood shifting earlier (e.g., into February) causes karst lakes to fill early, while other climatic conditions are still unsuitable for aquatic life. By the time organisms are ready to become active, the lakes are already draining.

As the climate warms, extreme events increase – precipitation and flood risk rise in Northern Europe, while Southern Europe faces water shortages, desertification, and salinity. Droughts become more frequent and intense, putting stress on ecosystems, increasing eutrophication and cyanobacterial blooms. Water pollution levels rise, drinking water quality declines, and groundwater replenishment slows. Erosion and sediment runoff increase, and rising sea levels threaten coastal areas and their infrastructure.

Already, 4.5 billion people live within 50 km of a problematic water resource, and by 2050, 40–79% of groundwater bodies are expected to be depleted. As of 2025, over 2,700 water-related conflicts had been recorded globally, with their frequency growing exponentially in recent decades. Terasmaa writes more on this topic here.

Consumer contributions

According to Preis, there are currently no simple or affordable solutions for removing pharmaceutical residues from wastewater – only complex and expensive ones. While ozone treatment for turning lake water into tap water is considered expensive and unaffordable for many cities and towns, purifying wastewater of micropollutants like drug residues is even costlier. “The issue isn’t whether it’s technically possible to clean water of a particular contaminant – modern technology can turn even a puddle into a spring. The challenge is doing it affordably,” he explains. His lab is developing a fundamentally new water treatment method – corona impulse electrical discharge (KIEL) plasma technology. As with any complex new solution, gaining support is slow.

Until cities are willing to invest in such solutions, we must protect our clean water ourselves. The healthier your lifestyle, the fewer medications you’ll need. Sergei Preis recommends moving more and eating less, avoiding unnecessary medications, abstaining from alcohol, and using bicycles and public transport. “And the ‘small things’: return unused medications to the pharmacy, don’t flush them down the drain!” he adds.

It’s even harder for individuals to fight agricultural runoff into surface water, but every consumer can make a difference through their purchasing choices. For example, organic food, less meat, and sustainably made textiles all help reduce industrial pollutants reaching nature.

However, if you think of saving energy by lowering your boiler temperature, that’s not a good idea, because bacteria – some of them pathogenic (like legionella) – can begin to grow in the tank. “In the best case, the water may develop an unpleasant smell. In the worst case, the consumer can become seriously ill from drinking such water,” says Preis. To avoid this, he recommends boiling drinks only from cold tap water and not drinking warm tap water.

What can each person do to reduce their water footprint?

• Read about the water footprint of your lifestyle here: https://ourworldindata.org/grapher/freshwater-withdrawals-per-1000kcal

• Keep in mind that every medication you use consciously will later be used unconsciously by other living beings. The healthier you live, the fewer medications you need.

• Take leftover medications to a pharmacy or waste station. Under no circumstances flush them down the toilet or pour them down the sink!

• The same applies to household chemicals, paint, and varnish residues.

• Cigarette butts belong in the trash, as they contain toxic chemicals and decompose very slowly in nature.

• Use environmentally friendly cleaning and cosmetic products—they help protect both nature and your own health.

Tips for saving water

In the kitchen

• If washing dishes by hand, don’t leave the water running. If you have a double sink, fill one side with soapy water and the other with rinse water.

• To drink cold tap water, keep a filled container in the fridge instead of letting the water run until it reaches the desired temperature.

• Wash fruits and vegetables in a basin. The rinse water can later be used for watering plants.

At home

• Run the washing machine and dishwasher only when they are fully loaded.

• Regularly check for leaks and fix them as soon as possible. The best way to detect this is by monitoring your water bills and meter for unusually high usage.

• Turn off faucets carefully and evenly after use to prevent unnecessary water loss.

In the bathroom and toilet

• Choose showers over baths. A bath uses nearly three times more water.

• Shorten your shower by 1–2 minutes and you could save up to 12 liters of water per day.

• Turn off the tap while brushing your teeth, washing your hair, shaving, or soaping your hands. This can save up to 40 liters of water per day.

In the garden

• Water early in the morning or late in the evening when temperatures are lower to reduce evaporation.

• Whenever possible, use previously collected rainwater for irrigation.

• Water the roots of plants, not the leaves. Water on leaves evaporates more quickly.

• If possible, use a watering can instead of an automatic sprinkler system.

• To avoid pressure problems, don’t water your plants during peak water usage hours between 6–10 PM.