Estimates put global NRW at 126 billion m3/year, costing some $39 billion/year (Liemberger & Wyatt, 2018), and average global NRW above 30%. Given these numbers, it’s of clear importance that awareness and access to viable solutions are supported. In Denmark, a variety of tools and efforts have been put in place to deliver such a low NRW level, and the nation has a formalized ambition to support the tunnelling of its solutions and expertise to outside regions.
Klavs Høgh, project director for water supply at the Danish engineering consultancy company NIRAS, remarks on his perspective on Denmark’s transition. Denmark are having some of the lowest water loss rates in the world. Klavs Høgh says: “In many places around the world, water loss is unfortunately very high. But we have proven that solutions can be implemented to dramatically improve that situation.”
Mette Neerup Jeppesen, manager for water supply at NIRAS, adds: “Having progressed through a long process to get NRW so low, we’re now in a position to share knowledge with others so they don’t have to go through the long learning process we went through.
The reasoning, Neerup Jeppesen explains, is simple: “We feel a responsibility to contribute to the technological development moving that direction and it is very often associated with healthy finances for our customers.”
Supply as an integrated system
What emerges from reviewing the ingredients to Danish success with NRW is that there is no single solution.
Høgh expanded on this, saying: “You have to look at optimizing your pipe infrastructure with separately metered district metered areas (DMAs). While, at the same time adding all the necessary “handles” such as intelligent pumps and valves that react to the actual demand to improve pressure control and flow. Thereby, combining with sensors and smart devices within a comprehensive management strategy. All sorts of factors are at play in lowering NRW; certainly, a longer-sighted solution, built for the future, is much more cost-effective in the long-run.”
Danish DMAs therefore represent a multi-faceted solution, incorporating novel physical technologies alongside sophisticated monitoring and operating of the network via supervisory control and data acquisition (SCADA) systems.
Pia Jacobsen, chief engineer – water reuse, at one of Denmark’s largest water utilities, Aarhus Vand, explains this path to securing such low NRW: “It’s a thirty-year story, with a focus on water usage and leakage. The adoption of DMAs has been a major source of gains, helping us to bring NRW to around 5%.”
But Jacobsen comments that implementing DMAs wasn’t an overnight solution. Rather, they had to be refined over time: “We’ve learned much about optimizing the size of a DMA for monitoring the water balancing and leakage. But also integrating their management through common SCADA platforms, and the operation of multiple teams responsible for different tasks working across.”
In Skanderborg municipality, similar works have been undertaken to improve supply. Here, the adoption of DMAs and smart technologies across the supply network has brought about flexibility and new options, and improved asset management. It’s also much more sustainable; enabling energy efficiency advances which are critical considering the significant amounts of energy required to produce and supply water.
“As early as 2015 we realized that consumption data can be used for much more than smooth billing,” comments Rune Kier, communication consultant in Skanderborg Utility and AquaGlobe – Water Solution Center.
“We did a pilot project called Smart Water City with Kamstrup, EnviDan and DHI aiming to use hour-by-hour consumption data to project future consumption and control pump operations. The pilot alone saved 15% energy the first year we introduced DMAs in a limited area, and a further 10% the next year on all our water works combined. We reached as low as 6% water loss. With that number comes much faster detection of leakages, fewer man hours spent and better asset management.”
Moving forward, Kier explained that Skanderborg Utility and AquaGlobe are undertaking a new project adding the partners the Alexandra Institute and Aarhus Vand. “It’s called CHAIN – Smart Water Network, and it explores the potential of Artificial Intelligence and machine learning in the supply net from well to tap. We believe it can bring us as low as 3% water loss as well as benefits in energy efficiency, water quality and security of supply”.