Our goal is to raise awareness of hydrological risks and help bridge the gap between science and practice

Cédric Hananel, Arctik

The materials published on the IMPREX website are made public for information, research and education purposes.

Always acknowledge the use of photos or videos by the use of appropriate copy and author rights. Prior to using the IMPREX visual identity, please contact Janet Wijngaard, janet.wijngaard@knmi.nl or Katrien Witpas, katrien.witpas@arctik.eu for authorisation. 

* Final Technical Report *

Overview of the results & their exploitation and dissemination. Selection of highlights of project outcomes and societal impacts.

PRESS RELEASE - Heat-waves, drought … time to start thinking big and bold

Immediate release


Another year of record-low rainfall and unprecedented heatwaves leading to worrying water shortages. Yet water users and authorities, especially in northern Europe, are struggling to understand the threat posed by climate change. It’s time to think big and look for bold solutions.

BRUSSELS, 20 September 2019 -- Greater awareness, better forecasting and long-term planning are key to preparing Europe for what could become the ‘new normal’ of extreme temperatures and water scarcity, according to IMPREX experts who have studied the hydro-meteorological risks and their comparative economic impacts on various water users.

Another summer of temperature spikes across Europe has forced governments to issue drought warnings and introduce sometimes drastic water-saving measures in those regions affected. But experts are calling for bolder, longer-term solutions to deal with prolonged dry periods under climate change.

Droughts can occur anywhere in Europe, in both high- and low-rainfall regions as well as outside the summer months. Yet, according to Marjolein Mens of Deltares in the Netherlands: “There is a belief in many northern European countries like the Netherlands and Belgium that water reserves are endless. Whether through lack of information or a behavioural disconnect, people don’t appreciate how their water use is affecting and affected by wider forces. To tackle this growing water-scarcity concern, strategic decisions are needed which will have long-term and potentially serious impacts.”

The problem is really a supply and demand one. Capturing and making better use of the rain that falls is a vital first step. With incentives, households could collect rainfall from their rooftops and store it in water tanks for watering their lawns and washing cars. With the right information, water authorities could better channel or buffer runoff to larger reservoirs, not letting it run freely into rivers and eventually the sea. On the demand side, ill-considered water use is a common problem. Practices like smart irrigation in the agricultural sector and reusing grey water – e.g. discharge from washing machines or industrial cleaning processes – are struggling to catch on.

IMPREX has tackled many of these subjects. Its work is part of a multi-country, multi-stakeholder initiative funded by the European Union’s Horizon 2020 to produce better insights into extreme hydro-meteorological conditions and their impacts in support of risk management and adaptation planning at European, national and regional levels.

Investigations in the Netherlands took a stepwise approach to understanding the problem of water scarcity and how it affects different water users and society in different ways. Some farms in the Netherlands, for instance, are linked to the country’s main water systems, which are holding up reasonably well in the drought. While others relying on groundwater are struggling. This means measures like buffering or redirecting water to low-flow waterways need to be more targeted.

Susanne Groot of HKV Consultants, an IMPREX partner, explains what the Dutch regional cases reveal: “Foremost we’re learning that local measures and efforts to mitigate climate change are not enough. Measures and impacts have to be considered in an integrated way. We encountered diverse views on what’s working and what’s not, and realised that perceptions change once we complete a thorough risk analysis in consultation with the stakeholder.

Being better prepared…

Investment in larger reservoirs in drought-affected areas is one solution. But in the end a more profound strategic review of land use may be needed, looking at where and what kind of agricultural activity is best suited in terms of freshwater availability. That is a national and even EU-wide discussion which would have huge economic and political ramifications.

On the importance of meteorological forecasting under climate change scenarios, IMPREX’s director Bart van den Hurk notes: “The 2018 drought really put into context the International Panel on Climate Change’s call to keep global average temperature to ‘well below 2°C above pre-industrial levels’. Climate models need to be improved to project the drought situation. Right now, they are overly focused on rainfall per se, when planners are also looking to be better prepared for droughts.”

IMPREX’s longer-term seasonal rainfall and water-level and -flow forecasting, as part of its case work on the Rhine in Germany, has a significant role to play in risk analysis and climate change adaptation measures by all of Europe’s major inland waterway stakeholders. Dutch water authorities facing low water levels in a region or across the wider system need to know further in advance when to start buffering. Accurate forecasts in 2018 came too late to prevent the drying out of vital reservoirs.

Unique new solutions

Over the past 30 years, droughts have dramatically increased in number and intensity in the EU. The number of areas and people affected by droughts went up by almost 20 % between 1976 and 2006.

Yet drought forecasting has remained largely unchanged. The solutions developed under IMPREX offer, for first time, a fresh perspective based on longer-time data series rather than what the experts call ‘characteristic drought events’.

Deltares’ Femke Schasfoort says: “With this data, we can also see for the first time the impact of droughts on Dutch society. The tools we developed help us understand the impact of water shortages on different sectors like agriculture, shipping, drinking water utilities, and on nature and biodiversity in general. We now have numbers to scale and compare the risks to shipping versus, say, agricultural water users. This is valuable economic data supporting important decision-making under changing socio-economic and climate conditions.”


Note to editors

For more information contact Marjolein Mens (marjolein.mens@deltares.nl)


IMPREX – Improving Predictions and Management of Hydrological Extremes – is an EU-backed initiative spanning nine countries to improve society’s ability to anticipate and respond to future hydrological extreme events (floods, droughts...) in Europe. It will enhance forecast quality of extreme hydro-meteorological conditions and their impacts. The knowledge developed by the project will support risk management and adaptation planning at European and national levels. 

About Deltares

Deltares is an independent institute for applied research in the field of water and subsurface. The main focus is on deltas, coastal regions and river basins. Managing these densely populated and vulnerable areas is complex, which is why we work closely with governments, businesses, other research institutes and universities in The Netherlands and abroad. Deltares is a not-for-profit organization based in the Netherlands with 800 employees worldwide and offices in five different time zones around the globe.


Drought (Copyright: Jannes Wiersema , KNMI)
Drought (Copyright: Jannes Wiersema , KNMI) - full size


PRESS RELEASE - Climate change’s lesser-known consequences: inland waterways

Immediate release

Transport along Europe’s inland waterways is vital to trade. Concern about poor flow due to low rainfall, even along major river systems like the Rhine, has spurred innovation in long-term forecasting and logistics planning

BRUSSELS, 23 September 2019 -- Not content to hope for the best, shippers who ply Europe’s inland waterways have turned to IMPREX, experts in hydro-meteorological analysis, for reliable longer-term water-level forecasts to plan and optimise shipments along the Rhine.

Germany hoped the record drought of 2018, which wilted crops and brought many farmers to their knees, was an aberration. One of the responses was for the country’s meteorological office to set up an early warning system. That service was put to the test sooner than expected, as unprecedented heatwaves hit Europe again this summer, confirming what many feared … that extreme events could become more frequent in the future. While much of the focus has been on how farmers are coping, less has been reported on the impact of low rainfall on vital inland shipping routes.

Bastian Klein of Germany’s Federal Institute of Hydrology (BfG) says: “Accurate, long-term planning is the key to efficient and competitive transport along Europe’s inland waterways. Just as a road haulier wants to know about planned road works and other potential delays to their shipments, water transport companies and their customers need to know what’s happening with their routes. They need reliable water-level forecasts at different lead-times to improve logistics planning and remain competitive within the overall transport market.

Coping with low flow along the Rhine

To be competitive, all transport companies need to maximise loads. But with major watercourses under stress from consecutive years of dry weather, lower water levels mean volumes have to be reduced to ensure safe passage. More than ever, vessels need better data and intelligence on the optimal loads and times to ship along various sections of the river.

German authorities called on IMPREX, the EU Horizon 2020-funded project, to connect the dots between meteorological forecasts and water dynamics along the Rhine, which is a major route for commodities such as grains and minerals, but also coal and other important fuel sources.

IMPREX offers stakeholders richer insights into extreme hydro-meteorological conditions and their impacts to improve risk management and adaptation planning at European, national and regional levels. Teams in Germany and elsewhere have put together bespoke forecasting tools to aid decision-making, which include the following pre-operational prototypes:

1) Ten-day water-level forecasts for operators to optimise route planning, for water authorities to plan maintenance work, but also for customers/industry to help plan shipments and better manage stock at the ports/loading points;

2) Monthly to seasonal flow forecasts for all major German waterways (Rhine, Elbe and Danube) required for medium- and long-term planning and optimisation of the water-bound logistics chain (stock management, fleet composition, production planning) including connections between waterways and other transport modes as well as waterway management.

Some unexpected beneficiaries

This fine-grained data support has helped shippers and their customers navigate difficult times. IMPREX’s long-term forecasts have also found an unexpected fanbase among road hauliers. Lorry companies use them to fine-tune their own logistics planning and ensure that that they have enough drivers ready when low flows are predicted and a back-up solution across land is needed.

Energy producers are another keenly interested sector in IMPREX’s intelligence reporting. Inland shipping remains a vital link in the coal supply chain, to produce electricity especially during periods of peak demand, such as in the winter. Better longer-term seasonal forecasts help power plants plan for coal supply contingencies and make sure the lights don’t go out when river levels are too low or too high for barges to safely navigate.

Managers of waterways influenced by tides are also using IMPREX’s long-term forecasts to estimate sediment build-up around harbours and waterways, to optimally plan their management strategies under the constraints of natural conservation.

These monitoring and reporting systems form the backbone of a set of tailored and very accurate forecast products. The tools are ready for use by the stakeholders involved in IMPREX and beyond.

Andreas Backhaus, Head of European Site Logistics Operations BASF SE confirms: “Barging is a vital transport mode for BASF – especially regarding volume and sustainability. IMPREX’s long-term forecasts for water levels on the Rhine are an absolute necessity for our inventory and supply management.”

The expertise developed under the project is thus uniquely placed to support risk management and adaptation planning in response to future hydrological extremes.


Note to editors

Read the full report, ‘Improving predictions and management of hydrological extremes’ 

For more information or quotes contact Bastian Klein: klein@bafg.de


IMPREX – Improving Predictions and Management of Hydrological Extremes – is an EU-backed initiative spanning nine countries to improve society’s ability to anticipate and respond to future hydrological extreme events (floods, droughts...) in Europe. It will enhance forecast quality of extreme hydro-meteorological conditions and their impacts. The knowledge developed by the project will support risk management and adaptation planning at European and national levels. 

About BfG

The Federal Institute of Hydrology (BfG) advises ministries (e.g. the Federal Ministry of Transport and Digital Infrastructure, BMVI) and the Waterways and Shipping Administration (WSV) in matters of utilisation and management of the German federal waterways. Being part of the portfolio of the Federal Ministry of Transport and Digital Infrastructure (BMVI), it is the BfG's mission to contribute to the implementation and operation of an efficient and environment-friendly transport system. By improving the national infrastructure the BfG wants to boost Germany's economic power, strengthen Germany as an investment and industrial location and secure its position in a European context.


Hamburg Harbour (Credit: Markus Promny BfG)
Hamburg Harbour (Credit: Markus Promny BfG) - Full size


Rhine at Braubach (Credit: Markus Promny BfG)
Rhine at Braubach (Credit: Markus Promny BfG) - Full size


PRESS RELEASE - Heat waves, climate change and toxic algal blooms: New forecasting tools

Immediate release

Concerns about the quality of drinking and bathing water are mounting after a summer of yet more toxic algal blooms

BRUSSELS, 20 September 2019 -- Better insights and tools to control the growing prevalence of toxic algal bloom in Europe’s inland waters, thanks to detailed investigations by the EU-backed IMPREX initiative.

Europe is leaving behind a summer of record heat waves and reports of widespread algal blooms in many of its rivers and lakes. Algae tend to thrive in sunnier conditions, higher temperatures and in more stagnant or low-flowing waters with higher concentrations of nutrients like nitrates found in fertilisers – a process known as eutrophication. Proliferating algae affect bathing and drinking water, and aquatic life and biodiversity struggle in oxygen-starved and toxic conditions.

Not all algae are dangerous; some species can even be eaten and used in cosmetics or as energy biomass. But those containing cyanotoxins, such as microcystis aeruginosa, can cause serious harm to humans and animals. This risk of more toxic blooms is expected to increase as temperatures rise, rainfall drops and waterways become more static under climate change conditions. This puts growing pressure on water authorities responsible for sampling and testing drinking and bathing waters.

Better forecasting and innovative methods to handle this growing threat are needed. IMPREX scientist and project manager at Cetaqua, Laurent Pouget notes: “Detecting the most dangerous type of cyanobacteria in raw surface water is complex and costly (~€100 per sample), which limits monitoring frequency. Water operators are only required to monitor treated water. Little is known about or done to prevent potentially dangerous blooms upstream. Due to its heavy reliance on lakes and open reservoirs for its drinking water, Spain has to be particularly vigilant.”

Pouget is lead author of a new report produced under the EU’s Horizon 2020-funded IMPREX, which traces the threat to urban water supplies in Europe posed by extreme weather. Advanced water-quality forecasts, honed through detailed case studies in collaboration with SUEZ in Spain’s Segura and Llobregat Basins and other sites, can help Drinking Water Treatment Plants (DWTP) and authorities responsible for Water Safety Plans monitor conditions and better predict potential threats, making water supplies safer and more resilient.

Isabel Hurtado of Aquatec, who manages risks linked to raw water intake in a DWTP in Murcia (ES) says: “Resilience is going to be more important as hydrological extremes become more common and unpredictable. Changing water conditions will have big implications on the design of water management practices. Actionable research like IMPREX’s is urgently needed to guide decisions. We want to know what’s going on with our climate, but also how to respond effectively.”

IMPREX’s detailed monitoring of algal activity, water conditions and enhanced climate projections provide decision-makers with the intelligence to make risk assessments based on changing hydro-meteorological conditions. Hurtado explains: “In the competition for resources between inoffensive and dangerous algae, greater instability in the weather and extreme heat can give the toxin-bearing bacterial strains the edge over the benign ones. We’ve monitored different algal growth and now know which were present at different times, indicating which are dominant and growing fastest.”

Four innovative services have been developed in the framework of IMPREX, using data to help water authorities and managers reduce risks, plan services and infrastructure and save on costs:
1) Tools for managing turbidity or murkiness in the water
2) Advanced control of cyanotoxin risks
3) Models for assessing climate change impacts on river pollutant concentration
4) Tools for monitoring and forecasting algae development in reservoirs.

SUEZ, a major water utility and one of IMPREX’s industry partners, is integrating these services into its wider operational platform. The project’s use of analytical tools and machine learning to transform monitoring data into predictive models is also showing great promise. More broadly, improved forecasting means better-informed decision-making on how to tackle potentially life-threatening algal blooms under changing climatic conditions.


Note to editors
Download the full report here
For more information or quotes contact Laurent Pouget: lpouget@cetaqua.com


IMPREX – Improving Predictions and Management of Hydrological Extremes – is an EU-backed initiative spanning nine countries to improve Europe’s ability to anticipate and respond to future hydro-meteorological extremes (floods, droughts...) and their impacts. The findings/tools developed by the project will support risk management and adaptation planning at European and national levels. 

Cetaqua represents a pioneering collaborative model among public scientific institutions, universities and water companies. This model has been established as a European benchmark in the application of scientific knowledge to water and the environment. Cetaqua’s mission is to anticipate society’s needs and propose new R&D&I solutions in order to ensure the sustainability and efficiency of the water cycle, while taking local needs into account. 

Tables and images

Services within IMPREX that tackle this problem
Services within IMPREX that tackle this problem


Algae - source: Unsplash
Algae - Source: Unsplash - full size


Media toolkit - IMPREXive game

As part of the launch of our IMPREXive serious game, we have made a media toolkit that can be used to promote the game. 

The kit includes:

banners and model posts that can be used on social media

some website banners

a short, accessible description of the game

a press release

a PowerPoint slide with one of the campaign images (plus an extra slide to add some info on)eu

For additional information or promotional materials, please contact Katrien Witpas at katrien.witpas@arctik.eu.

POLICY BRIEF - Probabilistic Approaches for Improved Flood Risk Assessment and Management under consideration of uncertainties

One of the challenges faced by Member States in implementing the Floods Directive is how to factor in uncertainties in flood hazard and flood risk assessments within flood risk management strategies. Tools are needed to support decision-making on appropriate flood measures under consideration of uncertainties. Here is how IMPREX can help.

POLICY BRIEF - The importance of including compound events in the implementation of the Floods Directive

Compound flooding, floods due to multiple flood drivers such as heavy rain, storm surges, or high runoff rates, has caused some of the most destructive floods in Europe. Still, the compounding nature of multiple drivers is not sufficiently emphasized in current flood hazard and risk scenarios developed, for example, in the context of the Floods Directive. This may lead to a biased assessment of flood risk, both for current and future climate conditions. This IMPREX policy brief presents guidance for policies that take into account the risks of compound flooding.

POLICY BRIEF - A new dimension in EU’s Climate Adaptation Policy: EU’s vulnerability to climate change impacts outside its borders

IMPREX poster - User needs assessment

DEPENDENCIES OF EUROPE’S ECONOMY ON OTHER PARTS OF THE WORLD IN TERMS OF WATER RESOURCES - Executive summary: EU’s vulnerability to water scarcity and drought

Executive Summary of the IMPREX Deliverable D12.1: Dependence of European economy on water issues elsewhere