Hydration in the Local Climate: How Much and What to Drink in Helsinki

Helsinki’s early July heatwave has triggered a sharp uptick in cases of mild dehydration at local clinics, as health officials report a surge in patients seeking advice on how much—and what—they should be drinking to stay healthy.

The recent spike in mercury—Monday saw a reading of 28°C at Kaisaniemi weather station—has coincided with school holidays, festivals like Tuska in Suvilahti, and Helsinki Day events in Esplanadi. Locals and tourists alike are filling parks and outdoor terraces, but few seem prepared for how much fluid is actually needed during even a short outing.

Thirst in the City: Where Helsinki Keeps You Hydrated

Helsinki’s city government has responded in recent years by expanding its installation of public water fountains along the Töölönlahti jogging route and near Kulttuuritalo, aiming to make access to clean tap water easier for active residents. The city’s Tap Water Helsinki campaign, launched in 2024 and managed by Helsinki Region Environmental Services Authority (HSY), also encourages people to carry reusable bottles and refill at public taps, citing that the city’s tap water routinely scores among the cleanest in Europe.

Cafés in the Kallio district, from Good Life Coffee on Kolmas Linja to the Oodi Central Library’s café, have begun offering free tap water on request—some even infuse their carafes with local herbs. Yet, as Helsinki’s nutrition experts point out, not all drinks hydrate equally. "Coffee, energy drinks, and sweetened sodas are still popular, but these can, over time, increase dehydration risk especially on hot days," one nurse at Mehiläinen Töölö admitted, noting that caffeine and sugar-laden choices are easily available on every corner from Rautatientori to Kamppi.

Data, Demand, and What to Drink Now

Why does this matter? According to the Finnish Institute for Health and Welfare (THL), even mild dehydration can result in headaches, sluggishness, and trouble concentrating—issues that have spiked since June, when Helsinki’s average daily temperature crept 2°C above 30-year norms. HSY estimates that during an average July, water consumption in Helsinki can increase by up to 30% (measured at an average 170 litres per person daily), with the vast majority coming from the home tap or public fountains.

Nutrition guidelines published by the City of Helsinki’s Health Services Department recommend adults aim for 1.5–2 litres of fluids a day, or more during active days outdoors. This advice, however, includes all beverages and water-containing foods—so a bowl of lohikeitto and a serving of strawberries both count. Still, experts emphasise that pure water remains the best hydration source, especially on sauna days or long walks along the shores of Lauttasaari. A reusable bottle in Helsinki typically costs 10–20 euros at sports shops like XXL or Stockmann, making preparation accessible.

As climate shifts bring longer spells of hot, bright weather to southern Finland, local authorities say Helsinki residents should get into the habit of checking their urine colour after exercise (it should be pale yellow, not dark), and always keep water handy when cycling the Baana or hiking at Keskuspuisto. Public health teams will be rolling out more Tap Water Helsinki pop-up refill stations at major parks and festivals this summer, aiming to reach more families and older residents. Ready access to water, not just at home but throughout the city, is fast becoming part of Helsinki’s wellness culture weathering the heat.