Copenhagen, Denmark

Copenhagen is internationally renowned for its innovative approach to climate and the environment. The city is working to mitigate the effects of climate change (manifested as severe rainfall events) by promoting and implementing climate-friendly and environmentally-conscious solutions, such as adding green spaces in the urban centre. The city is fully reliant on groundwater to meet its drinking water needs and its water tariffs are among the highest in Europe to support mindful consumption and support the protection of groundwater resources. There is strong political will and precedence to put forward green initiatives and residents are well-informed of environmental issues. Copenhagen has a very low rate of non-revenue water, owing to a proactive approach to survey the water supply and distribution network and a comprehensive benchmarking system that publishes information about water utilities across the country.


Key Information: Copenhagen is the capital and primate city in Denmark, with a population of approximately 660,000 in the municipality and 1.4 million in the urban area (Dyvik, 2023). The population is rising by 1,000 citizens every month and is expected to reach 700,000 by 2025 (Circuit, n.d.). The city is located on the eastern side of the island Zealand and connected to the Swedish city of Malmo via bridge across the Oresund strait (Dyvik, 2023). Copenhagen has experienced a number of severe rainfall events, namely cloudbursts, with the largest pouring down in July 2011 (IWA, n.d.). Protecting residents and businesses from the impacts of climate change, while also continuing to secure high quality drinking water for a growing population, are the city’s primary concerns related to water. HOFOR, the Greater Copenhagen water utility, is working to secure and protect future water resources for its customers by focusing on implementing climate-friendly and environmentally-conscious solutions (IWA, n.d.; HOFOR, 2023). Copenhagen’s drinking water supply is based entirely on groundwater extracted outside the city and the government’s official position is that drinking water should be based on pure groundwater which only needs simple treatment with aeration, pH adjustment, and filtration before it is distributed to customers (IWA, n.d.). 

Water Assessment:
Economics/Finance: Copenhagen is widely recognized as a leader in the global green economy (LSE, 2014). The Copenhagen region accounts for almost 40% of Denmark’s output and has enjoyed long-term stable growth, including while improving environmental performance and transitioning to a low-carbon economy (LSE, 2014). At the national level, Danish GDP per capita has ranked among the top 10 countries in the world (LSE, 2014). The water tariff for Copenhagen is around €9/m 3 (USD 9.85), set annually by the city government based on HOFOR’s proposed activities for the coming year (IWA, n.d.; State of Green, 2022). Two-thirds of the tariff covers handling and treatment of wastewater and one-third covers the drinking water supply, covering costs for groundwater protection, pumping and delivery of drinking water, and quality control (State of Green, 2022). While the water tariff appears high, domestic consumption has decreased by about 40% since 1980 due to a combination of rising prices and general environmental awareness campaigns (State of Green, 2022). In 2018, the average household spends approximately 1.4% of their household budget on water and wastewater services, well below a UN recommendation on affordable water, which sets a limit of 3% (State of Green, 2022). Despite aging network infrastructure, HOFOR has managed to keep the non-revenue water level at just 5.6% (State of Green, 2021). 

Politics/Governance: Copenhagen is aiming to be the first carbon-neutral capital city by 2025 (Circuit, n.d.). Energy and resource effectiveness and low carbon drivers are central to the carbon-neutral goal, and has been flagged as requiring substantial additional policy support, particularly in the areas of district heating, energy efficiency, waste management, and decarbonizing the transport sector (LSE, 2014). Broadly speaking, there is strong political support for creating a more liveable and resilient city. Working across sectors, Copenhagen is setting ambitious goals for the future, including a new vision called Co-Create Copenhagen with three key pillars: a liveable city, a responsible city, and a city with an edge; enabling strong citizen participation along the journey (IWA, n.d.).  In Denmark, two ministries are primarily responsible for regulating the water sector: the Ministry of Environment (responsible for environmental regulation) and the Ministry of Climate, Energy and Utilities (responsible for economic regulation) (State of Green, 2022). Traditionally, the Danish drinking water sector has been highly decentralized, however, since a reform of the sector in 2007, all water and wastewater utilities have been economically independent (State of Green, 2022). As the entity responsible for water supply and wastewater treatment in Copenhagen, in addition to providing district heating, cooling, and gas, HOFOR is working to incorporate sustainability considerations into their day-to-day operations using a 100-year sustainability vision (HOFOR, n.d.). HOFOR is owned by eight municipalities and the City of Copenhagen owns 73% of the company (State of Green, 2021).  

Ecological/Natural Science: Denmark aims to be the world’s first country entirely independent of fossil fuels by 2050 and almost 60% of the country’s electricity was produced by solar and wind energy (Wonderful Copenhagen, n.d.). Copenhagen is recognized as one of the most environmentally friendly cities in the world. As a result of its commitment to high environmental standards, Copenhagen has been praised for its green economy (LSE, 2014). The city has about 2260 hectares of green areas with public access, of which about 200 hectares are lakes and aquatic areas (Cömertler, 2017). Moreover, at least 80% of city residents live within a distance of 300m to a green space (Cömertler, 2017). Copenhagen harbour has undergone a large transformation in the last 25 years, turning from a former industry harbour to a recreational area where citizens go to swim at least 350 days a year (Wonderful Copenhagen, n.d.).   On the geographical side, the central area of Copenhagen consists of relatively low-lying flat ground while the hilly areas to the north and west are around 50m above sea level. Lying in the oceanic climate zone, Copenhagen has moderate precipitation year-round, with slightly higher rainfall from July to September. 100% of Copenhagen’s drinking water is sourced from groundwater resources, extracted 100m deep in lime rock (IWA, n.d.). 

Technical Science/Infrastructure: Acknowledging the future risks of climate change, the Copenhagen City Council adopted a Cloudburst Management Plan in 2012 to support the roll-out of 300 cloudburst projects over 20 years (C40 Cities, 2015). The projects focus on green infrastructure, which have functions that include creating shade and air circulation, provide opportunities for recreation and stress prevention for residents, and reduce noise and air pollution (C40 Cities, 2015). This forms part of Copenhagen’s broader goal of being carbon neutral by 2025.  The water distribution network in Copenhagen has a high average age, as 20% of the network pipes are more than 100 years old (State of Green, 2021). The low level of non-revenue water is attributed to the high quality cast iron pipes that were laid before 1945 (representing about 50% of the network), which have a low burst frequency (State of Green, 2021). The system is manually surveyed on a three-year cycle, combined with appropriate rehabilitation planning, which is based on a methodical selection of the pipes that are the most prone to bursts (State of Green, 2021). Denmark has also adopted an advanced benchmarking system, where information about drinking water and wastewater from utilities across the country is collected and published by the Danish Water and Wastewater Association (DANVA) in their annual publication “Water in Figures” (State of Green, 2022). The benchmarking is based on operational parameters and cost efficiency across the water sector and can support knowledge sharing and collaboration between utilities, government bodies, consulting companies, universities, and research institutions (State of Green, 2022). 

Social Science: Copenhagen has a long-standing tradition of pursuing green solutions that benefit both the environment and residents (Wonderful Copenhagen, n.d.). The city has around 550 km of bike paths and has invested an average of USD 12.4 million annually into cycling initiatives (Wonderful Copenhagen, n.d.). Between the 1970s and 90s, there were school-focused campaigns around environmental responsibility and conservation (Raidt, 2015). This has supported the buy-in and support for municipal and national sustainability initiatives and contributed to a high public awareness of environmental issues (Raidt, 2015). Copenhagen’s anticipated population growth will be a challenge for the city to overcome in regard to continuing to support green initiatives and protect groundwater resources while balancing increasing urban density.