Digital technologies are shaping our world and are at the center of policy and technological developments worldwide. These technologies generate technical, economic, environmental, and social benefits. In the social sphere, as well as the water management sector, digital infrastructure and rapid connectivity technologies present new opportunities.
Digital solutions are increasingly pivotal in various sectors, creating new opportunities for businesses, encouraging trustworthy technology, fostering an open and democratic society, enabling a vibrant and sustainable economy, and helping fight the effects of climate change. One area where the benefits of digital technologies are particularly noteworthy is in the water sector, which is the topic of this article.
The three main water sectors discussed in this article are Water Distribution Networks (WDNs), wastewater systems (WWSs), and hydropower. By leveraging digital solutions, these sectors are experiencing transformative changes that improve efficiency, reduce waste, and contribute to a more sustainable and resilient future.
Unlocking massive savings:
Digital technologies delivered about EUR 300 billion in capital and operating expenditure savings in the global water industry in 2016–2020 (0.29% of the global Gross Domestic Product), targeting water segments such as the treatment of wastewater, distribution, customer management, and metering of drinking water.
In the water sector, the most widely used digital technologies include real-time monitoring, modeling approaches to support decision-making, and optimization measures, for example in energy consumption and data-based decisions.
The three main water sectors:
Curbing water loss and energy waste with digital tech:
A water distribution network is a net composed of nodes, where water is injected or collected, and pipes where water flows, which link the nodes. One of the main problems of WDNs is associated with water losses (leakages), mainly due to poor maintenance/management, and ageing infrastructure causing leaks and pipe breaks.
Through digital technologies, it is possible to monitor and detect these losses in real time, acting quickly to correct the problem. In addition, digitalization allows the implementation of real-time water flow measurement systems, which enables supply system managers to monitor demand and water consumption and make timely proactive decisions. Digitalisation also allows us to identify patterns of water consumption by different categories of users, which can be used to predict and avoid failures in the distribution system.
The lost water from distribution systems all over the world can meet the demand of 200 million people, and the energy consumption for treating 1 m3 of water is 0.6–12 kWh and varies depending on the source of water (freshwater, groundwater, wastewater, desalinised water).
On average in the EU, a 5% decrease in water distribution system leakage would save 313 million kWh of electricity annually (0.01% of annual EU electricity generation). This is equal to the electricity usage of over 31,000 homes. It would also avoid the emission of approximately 225,000 metric tons of CO2.
Digital technologies for wastewater challenges:
Combined wastewater sewers are designed to collect the dry weather flow (DWF), consisting of sewage from households, industrial discharges, and seepage of groundwater, into the sewers, together with urban runoff, and convey a certain amount of the combined flow to a wastewater treatment plant (WWTP).
A WWTP generally receives a discharge of 4–6 times the average DWF in order to ensure the design pollution removal efficiency of the treatment process, although in some cases, it can be >6. When the sewer network discharge exceeds the conveyance capacity of the network, the WWTP cannot treat this surplus, and the overflow is released into the environment.
Combined sewers are a widespread reality in the world and the European Union. Pollution from combined sewer overflows (CSOs) exerts significant pressure on the receiving water bodies and raises concern as a water management challenge.
Real-time control (RTC), by means of digital solutions (digital twins), is emerging as a water management strategy for the reduction of CSOs, as it allows for better operation of hydraulic structures, such as gates and storage tanks within the sewer network.
In Denmark, the entire water cycle of Aarhus’s wastewater treatment plant became energy-neutral with significant digitalization investments. The carbon footprint was also cut down by 35% through the installation of sensors, new variable speed drives, and advanced process controls.
Improving the efficiency of hydropower:
The hydropower sector is highly interconnected with the environment and society, particularly ones that use large water reservoirs. Thanks to its flexibility, hydropower allows for the integration of volatile energy sources (wind and solar energy) and can also be hybridized with other energy technologies (e.g., floating photovoltaics and batteries). These systems are interconnected to each other in the so-called water–energy–food–ecosystem (WEFE) nexus, which is the interdependence of water, energy, and food security and ecosystems – water, soil, and land – and their mutually beneficial responses and synergies.
Digital solutions can be implemented both for monitoring and enhancing the quality of the surrounding environment (e.g., water inflow and discharge, water temperature and quality, fish habitat, water levels), for improving the overall efficiency and supporting the operation and maintenance sector, predicting and detecting possible future failures, reduce costs and increase resilience against physical and cyber threats.
The efficiency increase entailed by the implementation of digital solutions typically ranges between 0.5% and 2%, while the increased generation from reservoir management improvement was predicted as +5%, although it may be as high as +10%.
Quantifying the benefits of digital technologies in the water sector:
Quaranta et al. (2023) estimated the benefits entailed by digital technologies implementation in the European Union (+UK), including leakage reduction in WDNs, reduction of CSOs, and improved hydropower (and reservoir) operation.
The quantified benefits are EUR 5.0, 0.14, and 1.7 billion per year (0.4% of EU annual GDP), respectively, excluding environmental and social benefits, which may play a non-negligible role, but which are very hard to estimate in a large-scale study.
The benefit-to-population ratio ranges from 1.1 EUR/person/year (Belgium) to 59.1 EUR/person/year (Sweden), with an overall average EU aggregated value of 13.2 EUR/person/year (including the UK).
Challenges and Future Directions:
Financial Investment Needed for Digital Transition:
To foster the digital transition, a 2020 estimate shows that additional investments of around EUR 125 billion are needed per year in the European Union. This corresponds to 280 EUR per year per EU citizen.
Environmental Costs of Digitalization:
Data usage and consumption also come with an environmental cost, which is associated with water and energy consumption in data centers, and the rare earth material needed to produce the electronics. In 2021, the average European citizen used around 187 GB of data, an increase of 32.4% from 2020. Future projections for 2030 foresee that the use of digital technologies would increase water consumption to 0.8 m³ per person per year and energy consumption to 171 kWh per person per year in Europe, costing EUR 19.7 per person per year.
Energy and Carbon Footprint:
At present, digital technologies account for between 8-10% of our energy consumption and 2-4% of our greenhouse gas emissions.
Security and Technical Concerns:
Digital technologies are vulnerable to security attacks, including physical attacks on sensors, cloning, data theft, and high dependence on centralized servers. Moreover, challenges are also related to integrating up-to-date advancements in the IT sector on existing and operating stations that currently use obsolete systems.
Data Acquisition Challenges:
Data acquisition is not an easy task; for instance, in the EU, the number of monitoring points found today in drinking water networks ranges from zero to about five per 100,000 inhabitants, which is still extremely low.
The Role of the European Commission:
The digital transition, particularly in the water sector, is a core topic at the global level and especially in the EU, as it is one of the six priorities of the current Commission. During the Digital Decade, the European Commission is committed to delivering a Europe fit for the digital age. To achieve the ambitions set in the Digital Compass, the EU needs to step up investments in key digital technologies, as well as in relevant skills.
Investment vs. Benefits:
To foster the digital transition, an additional investment of around EUR 125 billion per year is needed, and just a few among the many benefits here quantified would fill almost 5% of the total costs (across all sectors, not limited to the water sectors).
