Urban water management is one of the services most affected by the impacts of climate change, threatening the capacity of service providers to deliver safe water, protect rivers and oceans, as well as protect people and assets from extreme water events such as flooding. 

Water, sanitation and urban drainage utilities can contribute up to 15% to their cities’ greenhouse gas (GHG) emissions. Therefore, utilities are significant actors in the path towards decarbonisation and net zero. 

With urgent action needed on mitigation, the International Water Association is launching a new webinar series, organised by IWA’s Climate Smart Utilities Initiative in partnership with DANVA, to raise awareness of key sources of GHG emissions from the urban water cycle and showcase pioneering net zero solutions.

With a focus on progress in the Nordics, the series will provide an overview of GHG emissions from wastewater treatment and the relevance of process emissions of nitrous oxide and methane. It will highlight progress made through the Danish national monitoring programmes for nitrous oxide and methane, share actions by progressive utilities and regulators, and provide a space for discussion and collaboration on mitigation. 

The series, structured in four webinars, aims to empower participants to understand where to focus, to develop insights into the monitoring and reduction of GHG emissions and to improve their GHG accounting methodologies and considerations.  

The first webinar ‘Towards a Climate Neutral Water Sector: the Nordic Experience’ takes place on 2 May. The webinar will focus on the main sources of emissions in the urban water cycle. The webinar will also present a recent collaborative document on the Nordic Principles for moving towards a climate-neutral water sector, focusing on GHG accounting approaches and on the importance of developing a common understanding. It will finish with a utility showcase by Bergen Vann, a progressive water utility from Norway that will share exemplary actions. Sign up for free here.  

The second and third webinars will focus on methane and nitrous oxide emissions respectively, sharing learnings from the collaborative Danish national monitoring programmes which have helped drive progress. The webinars will present quantification approaches, findings and successes in emissions reduction to date. The discussion will explore what has driven such progress and how these efforts have led to sustained action and motivated utilities worldwide in monitoring and reducing their emissions. 

The final webinar of the series will offer a systems view. Looking beyond GHG emissions, we will consider the role played by the water sector within planetary boundaries. This will showcase innovative life cycle carbon assessment which is being used in decision-making processes related to resource recovery.  

We invite practitioners, engineers, consultants, students and researchers, operators, and carbon accounting professionals to join the series and engage with IWA’s Climate Smart Utilities initiative to share knowledge and exchange practices for a climate neutral water sector. 

Save the dates!

Towards a Climate Neutral Water Sector: the Nordic Experience

2 May 13:00 BST, 14:00 CET  

Monitoring and mitigating methane: Danish lessons for global action  

26 June  

Monitoring and mitigating nitrous oxide: Danish lessons for global action   

12 September 

Climate Smart Water Futures within Planetary Boundaries  

3 October 

IWA’s Climate Smart Utilities Initiative 

Stakeholders interested in improving their climate resilience while contributing to significant and sustainable reduction of carbon emissions are encouraged to engage with IWA’s Climate Smart Utilities initiative. The initiative aims to deliver value to utilities and inspire the wider water professional community. 

The initiative offers several opportunities, such as: 

• A community of practice around adaptation and mitigation to climate change to support bridging science and practice and trigger the necessary cultural shifts and actions 
• A web platform an online space to share resources and contribute to the wider dissemination of the change agenda 
• A utility leaders peer-to-peer exchange programme to drive decision making towards Climate Smart 
• A Recognition Programme and Climate Smart Vision to inspire and increase awareness & encourage utilities to include climate change in their agendas 

By CEO of Kalundborg Utility, Hans-Martin Friis Møller & Head of the Secretariat in Kalundborg Symbiosis, Lisbeth Randers. The blog post is part of a series of perspectives leading up to the IWA World Water Congress & Exhibition in Copenhagen in September 2022.

In Kalundborg, Denmark, one company´s waste or residual is another company’s resource. This is the site of the world’s first Industrial Symbiosis, which has created value through a symbiotic and circular approach to industry and production for 50 years. The city’s industrial companies work together across sectors to share their surplus of energy, water, and residual materials.

Symbiosis saves partners and the environment 4 million m³ of groundwater every year by using surface water (corresponding to half of our groundwater use). We save the environment 586,000 tons of CO2 and recycle 62,000 tons of residual materials. Since 2015, this innovative process has helped reduce CO2 emissions by 80%.

Creating symbiosis takes time and requires data and mutual trust between the parties. It also requires experience, competencies, knowledge, and an innovative approach.

How does symbiosis work? Collaboration is key. Within the Symbiosis system, public and private industrial companies are physically connected through pipelines, so companies can share their surplus. Symbiosis allows companies to trade waste and resources. It creates profit on the bottom line and attracts talented students, researchers, and specialists to the area. Symbiosis can be the solution of the future as it facilitates sustainability and profit going hand in hand.

Our vision is that the Kalundborg Symbiosis will be the world’s leading industrial symbiosis with a circular approach to production. For us, symbiosis is a local partnership where one provides, shares, and reuses resources. We are currently exploring the possibility of expanding our collaborations into regional partnerships.

We plan to establish a green energy motorway in which excess heat is collected through interconnections of the various companies and transported to the capital’s district heating network. The aim is for the heat to be utilised in Holbæk to phase out natural gas.

Fig. 1: The figure shows the different streams in the symbiosis.

An example of green conversion

Using residual heat from wastewater, Kalundborg Utility has invested in Denmark’s largest heat pump which uses residual heat from wastewater. The heat from the industry’s wastewater is part of the city’s district heating solution. The heat coming from the wastewater is used in three ways:

1. The companies use the heat and the wastewater’s organic content to produce biogas.
2. At the treatment plant, the hot water speeds up the biological processes so that more than twice as much wastewater can be treated.
3. The heat pump utilises residual heat before discharging the treated wastewater.

The Kalundborg Wastewater Treatment Plant receives approximately 7 million m³ of wastewater per year The treated wastewater has an average temperature of 24-25 degrees Celsius and is led to a heat exchanger where a heat pump uses electricity to extract the energy and boost it up to 72-87 degrees for district heating. This takes place during periods when district heating is most necessary in the city.

By cooling the wastewater by 10 degrees, the heat pump can produce approx. 80,000 MWh district heating annually, covering over 30% of Kalundborg Utility’s annual need of district heating. The heat pump makes it possible to utilise even more of the heat from the wastewater from the various industries in Kalundborg.

This is just one example of green conversion amongst many within the Kalundborg Symbiosis.

Contact Kalundborg Symbiosis

We wish to share our knowledge regarding industrial symbiosis, how to facilitate a local partnership with resources in focus, how public and private companies work together – and many more insights our long experience has granted us.

Visit the Kalundborg Industrial Symbiosis (Tour 8) as part of the IWA World Water Congress & Exhibition and experience first-hand how private enterprises are exchanging residuals and by-products from industrial production in closed cycles – with significant water and energy savings! (Technical Tours | World Water Congress & Exhibition)

Contact us: symbiosecenter@kalundborg.dk

Learn more: www.symbiosis.dk

Registrations for the Congress are now open. Secure your seat at the world’s leading forum for water issues!

By Jeanette Agertved Madsen, EnviDan A/S. The blog post is part of a series of perspectives leading up to the IWA World Water Congress & Exhibition in Copenhagen in September 2022

The latest IPCC report made it very clear – once again – that the planet is under severe stress and urgent climate action is needed immediately. It is necessary for everyone to contribute to the sustainable reduction of greenhouse gas (GHG) emissions, including all sectors in all countries. This calls for ambitious national and international policies and collaborations across borders and sectors – water included.

Energy and climate-neutral water sector in Denmark by 2030

The Danish Government implemented a new climate law in 2020 with the overall goal of reducing the national CO₂ emissions by 70 percent in 2030 (compared to 1990 levels). This law was followed by several other initiatives, including a climate plan for a green waste sector and circular economy. This climate plan includes goals to reduce nitrous oxide (N₂O) emissions from wastewater treatment plants by 50 percent, and to implement a limit for emissions from WWTPs larger than 30,000 person equivalents (PE), no later than 2025. These national goals have pushed the Danish wastewater sector from focusing mainly on energy to implement tangible climate actions on other fronts.

A national model, inspired by Paris Agreement on GHG reductions, was introduced in 2021 by the Danish EPA. In this model, all water and wastewater utilities are urged to report CO₂ emissions and their plans for reducing these in the next 15 years. One of the results of the model is the ambitious goal of energy and climate neutrality by 2030. You can read more on this here: iwa-network.org/the-road-towards-an-energy-and-climate-neutral-danish-water-sector-by-2030.

The CO₂ emission from the production of Danish electricity is decreasing by the day due to more and more renewable energy production. This means that contributions to the GHG footprint coming from the wastewater sector are taking over as the biggest individual contributors – especially N₂O from biological nitrogen removal processes, and methane (CH₄) from the biogas system. Thus, it is no longer enough to focus on reducing energy consumption and increasing renewable energy production. More climate measures need to be taken to fulfil the national goals.

Comprehensive data and knowledge on N₂O emissions should be shared

The International Greenhouse Gas Protocol sets standards for measure and manage emissions, categorising them in three different ‘Scopes’. These are exemplified in a water sector context in Figure 1. Most often Danish utilities report on Scope 1 and Scope 2, whereas Scope 3 is less frequently addressed, despite covering a very substantial part of GHG emissions in water.

Figure 1: Definition of scope 1, 2 and 3 based in the water sector (figure is developed by EnviDan based on the Greenhouse Gas Protocol Standards).

The Danish EPA has funded several projects related to N₂O emissions, providing a good starting point for reporting direct emissions in Scope 1. This is one of the reasons why Denmark has come far in gathering knowledge on N₂O emissions, and several control strategies are now being tested and used at full-scale at Danish utilities.

The VARGA project (www.projekt-varga.dk/en/front/) is an example of one of these projects. It showcases the transformation of a traditional WWTP to a Water Resource Recovery Facility (WRRF) and can be visited as part of the World Water Congress & Exhibition technical tours programme: Tour 2, Avedøre WWTP (worldwatercongress.org/technical-tours).

More than three years of online data on N₂O emissions have been collected, and a range of control strategies have been tested on-site. The results showed reductions of 30-80 percent (depending on the strategy) without compromising the nitrogen removal.

These experiences, together with the ambitious upcoming implementation of a limit on N₂O in Denmark, are key tools for effective emissions reductions that can serve as inspiration for other countries on the road to Net Zero.

Don’t get lost in operation

As mentioned earlier, Scope 3 is now starting to gain traction in the wastewater sector. Here in particular we can find CO2 emissions from construction. We know from other sectors that this has a huge impact, especially when building completely new WWTPs. So far, Danish utilities have focused mostly on CO₂ from operations as part of their reporting activities.  But now is the time to start expanding our gaze to include wider climate goals and also consider indirect emissions.

More information and resources

IWA is holding a series of webinars on process emissions, focusing on monitoring, management and mitigation of GHG emissions, including process emissions, carbon dioxide, nitrous oxide and methane. Masterclass 3 on Methane in Wastewater is scheduled for 23 June, 11:00 UK time. Find out more and register here.

IWAP has recently published a book on Quantifying and modelling of fugitive greenhouse gas emissions from urban water systems.

Finally, IWA looks forward to sharing ideas and knowledge at the IWA World Water Conference & Exhibition in Copenhagen, 11-15 September 2022. The Congress will offer many opportunities for water professionals and utilities to learn from emerging research on climate adaptation, mitigation, and much more!

Registrations for the Congress are now open. Secure your seat at the world’s leading event for water professional

Like all countries across the globe, Norway is not immune to climate change. Increased precipitation and extreme weather events in the country mean that water and wastewater systems have a growing vulnerability to water-related risks, which has led to the need for adaptation approaches to be adopted. Bergen, the rainiest city in Europe, considers stormwater as a resource. The city is shaped by decades of giving stormwater time and space, with emphasis on nature-based solutions and interdisciplinary collaboration.

Bergen aims to be Norway’s greenest city and a pioneering city with regards to environment, sustainable development and climate adaptation. Specific targets include becoming fossil free by 2030 and a 1.5-degree city by 2050, having zero-emission construction sites by 2025and increasing climate adaptation especially through blue-green infrastructure.

Adapting to climate change

In the quest to adapt to climate change, Bergen has for many years had an interdisciplinary and interdepartmental approach to stormwater management. As a leader in this area in Norway, Bergen developed a Municipal Stormwater Management plan that: 1) prioritises stormwater management; 2) ensures that stormwater management is integrated in all land use planning and urban development; and 3) ensures that blue-green infrastructure for stormwater management is a mandatory first choice. Training of relevant stakeholders in the Stormwater Management Plan has further accelerated this plan and raised awareness across disciplines. In addition, Bergen municipality has a monthly Interdepartmental Stormwater Forum, to keep stormwater high on the agenda and ensure continuous collaboration. Bergen also has a long history of international collaboration and knowledge-sharing, including more than 12 years of EU projects on climate adaptation, including the ongoing BEGIN project (on blue-green infrastructure through social innovation).

The integration of blue-green infrastructure for stormwater not only ensures significantly reduced flood risk, but also multiple co-benefits in health and biodiversity which improve liveability in Bergen. In attempts to monetise all these benefits, estimates show that the long-term financial benefits of using blue-green infrastructure to reduce flood risk in the municipality area are in the range of €33 million.

Bergen also has measures to enable climate adaptation for the forecasted increase rise in sea-level. As low-lying areas are at risk, all new areas below a certain altitude or with larger flood risk require water locks and pumping for wastewater infrastructure. A separate pumping system for wastewater infrastructure has been constructed for the historic “Bryggen” – a central, low-lying, and vulnerable water-front, with UNESCO-listed sites dating back to 1070 that require extra protection. In the coming years, an interdepartmental risk-based plan for Bergen with regards to the forecasted sea-level rise will be developed, considering the need for greater physical barriers.

Mitigation actions

Actions around mitigation will reduce greenhouse gas emissions and contribute towards Bergen becoming a 1.5-degree city by 2050, meeting the goals of the Paris Agreement.

The utility strategy for Bergen Water specifies the use an energy management system, with a circular economy approach which also reduces non-revenue water and emissions. Energy-use reduction and cost savings are driving utility’s mitigation actions. The utility is able to produce 60% of its energy through a combination of the utility’s biogas production from wastewater sludge and water turbines connected to the water intake from high in the mountains to the drinking water treatment plants. Energy consumption in operations has been reduced by 15% between 2018 and 2020, and further reduction is expected in the coming years. Another feature providing great energy savings is trenchless (no-dig) infrastructure management. For many years, Bergen has been now using a high percentage of trenchless solutions for renewal of pipe infrastructure. In 2020, around 80% of wastewater pipes were renewed with this method. Trenchless technologies not only save large amounts of energy in the construction phase, but also time and are less of a nuisance for citizens.

The utility has strived to become carbon neutral since 2018 and has a tool to map its carbon footprint. Bergen Water’s self-developed climate footprint tool includes both direct and indirect emissions, with a level of detail that is not only a leading approach in Norway, but also internationally. The tool provides an overview of the main sources for emissions and is the foundation for measures to reduce greenhouse gas emissions. For example, chemicals and filter materials have been replaced based on the footprint assessment results. This, together with the reduced energy consumption at treatment plants, as well as the introduction of a biogas treatment plant operation optimization process, has resulted in a 1/3 reduction of Bergen utility’s carbon footprint since 2018.

Data and calculations from the climate footprint tool have also been used for estimating expected levels of emissions in procurement and monitoring in line with international climate agreements. Bergen Water is also involved with IWA’s Climate Smart Utilities initiative and the Norwegian Water Utilities Climate Footprint Tool users forum – where shared experiences with the Bergen tool has been key in shaping a national tool.

Bergen Water follows the principles of a circular economy, by limiting resource and energy consumption and by producing renewable energy and fertiliser from wastewater. Resource usage has been minimised by limiting chemical usage as well as encouraging citizens to limit water consumption. From the biogas plant, 100% of the biosolids are sold as fertiliser in Norway, and 100% of the biogas produced is utilised as fuel by buses in Bergen.

In 2021 the first zero-emission construction work of the utility started, using 100% electric excavators. Already since 2020 all new contracts have required 30% weight on fossil-free construction sites, and from 2023 this will be a qualification requirement. Bergen municipality aims to have zero-emission construction sites by 2025. The municipality collaborates with a local energy company for mobile charging of construction equipment, an innovative project supported with investments from the Norwegian National Energy Fund.

Communication with citizens

Bergen Water has communicated all these actions to its citizens through public communication campaigns and social media, encouraging more sustainable behaviours like reducing their water use in households. These will save energy and resources, but also help adapt to climate change by managing demand.

Through the BINGO project, Bergen had several citizen engagement initiatives, including communication with citizens on how they are relevant local stakeholders in flood risk management and preparedness. A website was launched where citizens can easily share photos from their phones of flood related incidents and situations, giving valuable information for the Utility to follow up.

To further highlight the role of rain in Bergen, a large interactive art installation “The Art of Precipitation” will soon be installed on the main city square as part of the BEGIN project. The installation will visualise the weather in real time, and display precipitation in the last hour, day, week and month, as well as climate change information. A linked website will provide more detailed information and resources. The Art of Precipitation will be a unique way for building citizen awareness on stormwater, and to celebrate rain as a resource.

Lessons learned

1. Climate adaptation measures need to happen in collaboration, and need to be integrated with existing land use planning. This is happening in Bergen’s Municipal Stormwater Management Plan and continuous interdisciplinary and interdepartmental work.
2. Climate footprint calculations are a powerful tool, especially to identify measures to reduce greenhouse gas emissions.
3. National and international knowledge sharing accelerates everyone’s success. Over 15 years of EU projects have been key for Bergen.
4. A shared vision among all relevant stakeholders is key to ensure goals are met.
5. Stormwater is a valuable resource, and blue-green solutions to handle rain provide a long list of co-benefits for more liveable cities.

For more information contact:

Marie R. Sagen

Useful links

northsearegion.eu/begin/about-us/

connectingnature.eu/oppla-case-study/20402

northsearegion.eu/begin/bgi-pilot-projects/bergen/

Norway: Carbon-neutral as soon as 2030. Nordic Energy Research. nordicenergy.org/figure/ambitious-climate-targets-and-visions-for-all-nordic-countries/carbon-neutral-as-soon-as-2030/

Submit your Utility Case Story

Feeling inspired by this story? There are many other Climate Smart Stories worth celebrating. If you are interested in submitting your utility story and celebrate your achievements, join the Climate Smart Utilities Recognition Programme or contact Carlos Diaz.

In September 2022, an event to celebrate Climate Smart Utilities will take place at the IWA World Water Congress & Exhibition in Copenhagen, where top applicants will be invited.

Blog post by Karin Klitgaard, Director of Environmental Policy, Confederation of Danish Industry and member of the Danish Water Vision. The blog post is part of a series of perspectives leading up to the IWA World Water Congress & Exhibition in Copenhagen in September 2022

International collaboration is key to unleashing the potential of an energy and climate neutral water sector. But in all its essence, proper homework starts at home. As such, Denmark in 2019 established 14 Climate Partnerships to forge financially viable paths where corporations and governments work in tandem towards energy efficiency, greenhouse gas reduction, and greener industries.

The Climate Partnerships were tasked with formulating recommendations as to how their sector can contribute to reducing emissions and reaching the 2030 goal. With the dual objective to make the world more sustainable while ensuring green growth in Denmark, the effort sought to drive conscientious and concerted action within and across sectors.

Amongst more than 400 tangible recommendations, the Danish Climate Partnership for Waste, Water and Circular Economy suggested in 2020 to strive for an energy and climate neutral water sector in Denmark by 2030.

As described by Lars Schroeder, CEO of Aarhus Vand, who served as vice chair for the partnership, “transforming for energy- and climate neutrality within 10 years is an ambitious, yet realistic and achievable goal”.

Echoing the optimism, this blogpost gives an update on the work, and the voluntary agreement to reach energy and climate neutrality by 2030.

Collaboration between the stakeholders in the water sector is a prerequisite to aim towards a goal such as energy and climate neutrality. In Denmark, we started our journey in 2015 establishing the Water Vision cooperation, a public-private partnership aiming to promote a sustainable and innovative Danish water sector. The partners in the Water Vision are the Confederation of Danish Industry (DI), DI Water, the Danish Water and Wastewater Association (DANVA), representing water utilities, the Danish Environment Technology Association, and the Ministry of Environment, in cooperation with Danish universities.

Introducing ‘The Paris Agreement’ for the water sector

Since the formulation of the energy and climate goal in the climate partnership in 2020, the Danish parliament has made it an official national target. To keep track on the sector’s progress, the Danish EPA asked all Danish water and wastewater utilities to report their ambitions for the coming years on a voluntary basis. A process inspired by the Paris Agreement on GHG reductions. A high level of commitment from the sector has resulted in participation from most of the utilities, and the ambitions will be incorporated in a report outlining a 2030 forecast of the situation.

Many tools will be used by the utilities to move towards the energy and climate neutrality goal. Among the most important are:

• Process optimisation and focus on energy efficient equipment and operation
• Online sensors and real time regulation strategies
• Increased energy production from biogas
• Heat generation for the district heating system with heat pumps on the effluent water
• Afforestation on drinking water supply areas to protect groundwater
• Control of nitrous oxide from process tanks and methane leakage from digesters and sludge processing

The results are promising. Denmark is moving quickly towards energy and climate neutrality and a climate positive water sector is expected to be reached earlier than the 2030 deadline.

With the current momentum, I am confident that new developments and innovation in more effective and efficient methods can take the Danish water sector even further. This goes for both the drinking water supply and the transportation and treatment of wastewater. One key element here will be digitalisation and online control, which can result in reduction of greenhouse emissions and energy savings, as well as a reduction of water loss and higher effluent quality.

While Denmark is on the right track, there is still a long way to go and a lot to learn. As such, we are looking forward to sharing ideas and gather inspiration with new partners and old friends at the IWA World Water Conference & Exhibition in Copenhagen this September. On 11-15 September, we invite interested parties to join a selection of technical tours to some of Denmark’s leading water projects and facilities. With our eye and efforts firmly focused on the joint goal of energy and climate neutrality, we are looking forward to sharing Denmark’s contribution to this global endeavour.

Registrations for the WWCE are now open. Secure your seat at the world’s leading event for water professionals.

Population growth, urbanization and persistent drought are straining water resources in various regions around the world, while pollution and contamination compound these challenges. As this situation intensifies, water technology companies like Xylem are working to advance the conversation on sustainable water supply strategies, including the use of recycled water – or reuse water – to tackle water shortages.

The reality is that water scarcity is an issue facing communities in every corner of the world, but solutions exist to address this challenge. Advanced treatment technologies have demonstrated that wastewater can be purified well beyond drinking water standards and reused safely for both potable and non-potable purposes.

Reusing water can also have numerous economic benefits, reused water is less expensive than generating water through other technologies such as desalination, which means savings for both public utilities and citizens.

Advanced treatment technologies play key role

Advanced technologies are a key part of the foundation to support the development of potable reuse projects. New developments in oxidation-enhanced, biologically active filtration and UV disinfection are helping utilities around the world achieve reuse water quality standards, while delivering optimal performance, reliable operations and substantial energy savings.

Xylem is engaged in initiatives to build support for water reuse throughout the world:

• In California, advanced treatment technologies are helping to combat water shortages due to drought. For example, the Santa Clara Valley Water District is using ultraviolet (UV) light to produce recycled water for use by commercial and industrial customers, and the city of Los Angeles is incorporating UV light and chlorine in a cutting-edge advanced oxidation process to augment dwindling groundwater supplies. Xylem’s ozone and biologically active filtration processes are also being provided to produce high-quality water to supplement surface water supplies in San Diego.
• Using a multi-step disinfection process, Hampton Roads Sanitation District (HRSD) in Virginia Beach, Virginia, implemented an innovative water treatment program called SWIFT (Sustainable Water Initiative for Tomorrow). The program puts highly treated water through additional rounds of advanced water treatment to meet strict drinking water quality standards. SWIFT water is then added to the Potomac Aquifer to help slow and potentially reverse the shrinking of land due to withdrawal, help restore the health of the Chesapeake Bay and give the region a sustainable source of groundwater.
• In Saudi Arabia, a sewage treatment plant was expanded to help meet the country’s ambitious target for water reuse. An integrated wastewater treatment system from Xylem helps generate over 52 million gallons per day of treated water per day.

Expanding water reuse practices and customizing water treatment options such as Ozone Oxidation, Biologically Active Filtration, UV Disinfection and Advanced Oxidation Processes are increasingly necessary for water utilities to develop resiliency against local water challenges that range from protecting the environment to securing long-term water supply independence.

Wide-scale adoption

As climate change and continued population growth put even more pressure on already overstretched water resources around the world, water reuse applications are becoming increasingly important.

Accelerating the adoption of reuse technologies requires a combination of smart water policies and public education. As support for public policies to promote the use of recycled water and advancing technologies become more affordable, the treatment and recycling of wastewater for potable and non-potable use will continue to grow. We must spread the word that water reuse is a viable, safe and sustainable solution that will be essential to help solving the world’s future water needs. Ultimately it is the water’s quality that counts, and not the water’s  history.

How well water issues are managed will materially affect how far and fast greenhouse gas emissions can be reduced to help keep warming limited to 1.5 C. How can water sector professionals effectively enable emission reductions?

Hydropower provides one example of the links between water and emissions. The International Energy Agency has reported that in 2020, hydropower supplied one sixth of global electricity generation, making it the single largest source of low-carbon power – more than all other renewables combined, and advised that to achieve net-zero emissions by 2050, much more hydropower capacity would be needed (IEA).

Because of the effect of hydropower on the timing and scale of water flows downstream, any new or enhanced hydro schemes will affect water users and downstream communities and the environment. In most if not all countries, such schemes cannot progress without also managing the complex and often controversial trade-offs involved.

The use of hydrogen for liquid fuel also requires lots of water, with every litre of hydrogen consuming nine litres of water. Any new freshwater demand for this clean energy source will also affect water availability for other purposes and require governments to resolve the socioeconomic and environmental trade-offs.

Water managers and advisers have a key role to play in keeping the world under 1.5 degrees of warming by assisting governments to understand and work through such issues of competing needs for water and to implement the best overall solutions. For more on this opportunity, and what you can do, have a look at my article on Devex.

You can read more about water and climate issues in Water Policy Group’s Global Water Policy Report 2021: Listening to National Water Leaders. This report reveals the importance of climate risks from the perspective of water Ministers and top water officials from 88 countries from all regions.

IWA also invites you to discover the Climate Smart Utilities initiative, which aims to guide utilities in their mitigation and adaptation journey.

Day by day, the energy accounts of many Danish wastewater treatment plants are looking better and better. Consequently, many wastewater companies look into a future, with potential energy self-sufficiency.  

Wastewater is increasingly becoming a resource that can be utilised and contribute to the green transition – thanks to new technologies and innovative thinking. On one hand, new technologies that save energy and make the plants more energy efficient are continuously implemented. On the other hand, new methods of producing energy – e.g. biogas – constantly increase productivity in the sector.

In other words, the potential gets bigger and bigger to a certain level. This means that wastewater treatment plants in Denmark are getting better at utilising the resources in the wastewater. Not only can they produce the energy they need to treat the wastewater, they are also able to produce enough energy to sell the excess.

Better utilisation of resources and production of energy is high on the agenda at wastewater treatment plants in Denmark. It is intrinsic to the way Danish wastewater companies think today: That wastewater is a resource and is no longer perceived a waste product.

This development is beneficial to the green transition.

Climate legislation expedites the development

On 16 June 2020, the Danish Government with bipartisan support from the Parliament published a new climate agreement for a green waste sector and circular economy as a part of the specific execution of the Climate Act. The agreement sets a direction for the country’s wastewater companies. Among other things, it focuses on the energy consumption in the sector, energy production, and possible export potentials.

It is especially the large wastewater companies that treat significant amounts of wastewater, who are now able to boost their bottom line in regards to their energy accounts. In many places around Denmark, the development is already in motion.

New report leads the way

A new report devised by NIRAS and one of Denmark’s largest utility companies (VandCenter Syd) for the Danish Environmental Protection Agency outlines both potentials and challenges in the wastewater sector’s energy- and resource utilisation. The report was created based on reviews of eight treatment plants. It will serve as an inspirational catalogue for treatment plants and summarise a long list of opportunities, methods, and technologies for increased energy and resource utilisation.

Broadly speaking, there is a tremendous potential to save and produce energy – and thereby also reduce CO₂ emissions – via energy optimisation of wastewater treatment plants. The report highlights a number of these opportunities and technologies – and some of which are completely obvious, with initiatives that are both profitable and have short pay-back periods.