In Denmark drinking water is produced from groundwater. In fact, groundwater suitable for production of drinking water can be extracted from almost everywhere in Denmark.
Because of this, groundwater is a very important ressource i Denmark - both for our drinking water supply and the aquatic environment. In Denmark we protect our groundwater by preventing contamination from pollution. In other words Danish groundwater policy is based on prevention of pollution rather than water treatment.
The Danish Environmental Agency works both to map the groundwater, protect it and monitor it.
Danish drinking water supply structure
We have a decentralized water supply structure in Denmark. This means that the drinking water is typically produced at a waterworks locally. More than 95% of Danes receive drinking water from the country's approx. 2,600 public water utilites.
The water utilites have very different sizes. The largest water supplies supply water to several hundred thousand people every day, while the smallest supply water to 10 properties. The production apparatus of the largest water utilites often consists of several waterworks, many and long distribution lines and hundreds of boreholes. The smallest public water utilites may consist of a small waterworks, a single borehole and shorter mains.
The largest water supplies, which sell or treat more than 200,000 m3 of water per year, are covered by the Water Sector Act, which regulates the organizational and financial conditions for Danish water and waste water supplies.
In addition to the water utilites, it is estimated that there are approx. 50,000 very small water utilites– i.e. water utilites supplying fewer than 10 properties. These water utilites supply a few percent of Danes with drinking water. The majority of these are private individual collectors who only produce drinking water for their own consumption.
At the waterworks, groundwater is oxygenated and filtered at a before it is pumped out to consumers' taps. In rare cases, however, advanced water treatment is necessary to ensure satisfactory drinking water quality.
The Danish Ministry of Environment and the Danish Environmental Protection Agency are responsible for Danish legislation on drinking water, including e.g. protection of the groundwater, regulation of wells and boreholes, the quality requirements for drinking water and the control of drinking water, as well as providing guidance on the regulation.
The Danish municipalities have authority regarding water supply, and must therefore approve their local water utilites' control programmes, supervise whether the water supply meets the requirements for drinking water quality and inspect the local water utilites' technical facilities. A number of the municipality's decisions are subject to notification obligations to the Danish Environmental Protection Agency.
The responsibility of the water utilities is to operate the water supply efficiently and ensure that the drinking water complies with the set quality criteria. The responsibility for checking the quality of drinking water lies with the individual water utility. The utilities build and maintain their pipelines up to the property lines.
The consumers are responsible for maintaining the pipeline within their property. In case the consumer doesn't get water from a water utility but produce their own supply, it is their own responsibility to ensure that the drinking water is of sufficient quality.
Preventing water loss
Danish drinking water providers have one of the lowest water-loss rates in the world. This is confirmed by the website www.leakssuite.com, run by one of the world's leading experts on the subject, Allan Lambert, who is part of the Water Loss Specialist Group of the International Water Association (IWA).