Keeping NRW low through good management in Copenhagen

HOFOR - Greater Copenhagen Water Utility supplies around 700,000 customers in Copenhagen with drinking water.

The residents of the Danish capital consume approximately 31 million m3 water annually. The distribution network has a high average age, as 20 per cent of the network pipes are more than 100 years old. Despite this, the utility managed to keep the NRW level at just 5.6 per cent in 2019. Analysis shows that the cast iron pipes laid before 1945 have a low burst frequency. The high quality of these pipes, representing 50 per cent of the network, is key to the low NRW level. The real water loss in 2019 was 5.0 m3/km/day and the Infrastructure Leakage Index  (ILI) was 2.6. A low NRW value is achieved through appropriate planning and maintenance.

The water loss has been kept low through systematic leakage detection, where the system is manually surveyed in a three year cycle, combined with appropriate rehabilitation planning. The network rehabilitation planning is based on a methodical selection of the pipes that are most prone to bursts. The selection  considers the pipe material and age as well as leakage and burst history. To improve the balance between replacements and maintenance,

HOFOR is adopting an asset management and a management information system. The systems will also help optimise the periods between active leakage detection, aiming to achieve a higher degree of performance based asset management.


About author

HOFOR  is the largest utility company in Denmark in our core business areas: water supply, wastewater management, district heating, district cooling and gas supply. We also build wind turbines. We focus on sustainable supply, renewable energy, adjustment to the climate changes and improved handling of extreme rain. The aim of our activities is to create sustainable cities - in cooperation with municipalities, other companies and our customers.

Primary contact
Astrid Skotte

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