Climate change is increasing health risks in coastal environments. Warmer water, heavy rainfall and runoff can make bacteria, viruses and other waterborne pathogens more likely to occur or spread. But people using beaches and bathing waters cannot usually see these risks when they decide where to swim, bathe or spend time by the sea.

Beach users can see the weather, waves, crowds and facilities. They cannot see E. coli, enterococci, Vibrio bacteria or cyanobacteria in the water.

In this study, we wanted to know:

If people have better information about waterborne pathogens and health risks, does this change what they know, what they value, where they choose to go, and what kinds of public policies they support?

From our research, the answer is yes – but the story is more intricate than “information changes behaviour”.

The University of Warsaw team, led by Professor Mikołaj Czajkowski, studied two different roles of information.

The first is timely risk information. This means access to current or recent information about water quality, such as monitoring results, warnings, forecasts, apps, information boards or disclosure systems. This kind of information helps people make decisions when risks are otherwise invisible. We find that people value access to this information and are willing to travel further to use bathing sites where water quality is monitored more frequently.

The second is risk education. This means explaining what pathogens are, how people can be exposed, who may be more vulnerable, what symptoms can occur, and how people can reduce risks. This kind of information changes what people know, and it also changes what they value. After receiving pathogen-risk information, people placed greater value on monitoring and on policies that reduce infection risks.

The team studied these questions using a panel survey of people who had visited the  Gulf of Gdańsk or the Vistula Lagoon in Poland for recreation or leisure within the previous 36 months. The study combined stated-preference methods with reported trip behaviour. This means it did not only ask people what they might do; it also included information about their actual reported trips and recreation demand.

Why is this work important?

The Gulf of Gdańsk and the Vistula Lagoon are among Poland’s most important coastal recreation areas. They attract many visitors, especially in summer. At the same time, parts of the system are semi-enclosed, with limited water exchange and vulnerability to runoff and pollution events.

This makes the area a useful real-world setting for studying water-quality information. The risks are real, but they are not always visible or easy for the public to understand.

Better communication could help in two ways. It could help people reduce exposure by choosing safer places or times for bathing. It could also increase support for investments in monitoring, warning systems, forecasting and water-quality improvements.

Research highlights

• People value water-quality information. Respondents were willing to travel further to use bathing sites with more frequent water-quality monitoring. This shows that timely information is not just a technical feature of the system; it is something beach users actively value when making choices.
• Risk education changes behaviour and preferences. When respondents received credible information about pathogens and health risks, they learned more and placed greater value on risk-relevant measures, especially water-quality monitoring.
• Risk education also changed policy preferences. In a later policy-choice experiment, people who had received pathogen-risk information showed different preferences for mitigation and adaptation policies, including policies that reduce infection risk and improve monitoring.
• We can express these policy values in monetary terms. Using state-of-the-art stated-preference and econometric methods, we estimated willingness to pay for policies that reduce health risks and improve monitoring. This means the results can feed directly into cost-benefit analysis.
• Some effects were still visible about one year later. Prior exposure to pathogen-risk information was associated with changes in support for policies that reduce infection risk and improve monitoring.
• The study includes both stated choices and reported trip behaviour. The strongest causal evidence comes from the repeated choice experiments, but the travel-cost module also suggests that information is associated with changes in recreation demand and reported trips.
• Information should be treated as part of adaptation policy. It does not replace cleaner water, monitoring infrastructure or physical safety measures, but it can complement them and should be included in cost-benefit analysis.

Method

Before developing the survey, the team carried out background research on water quality, beach closures, monitoring systems, regulations and existing public information sources in the region. The survey was designed to connect knowledge, preferences, choices, behaviour and policy support.

The study used three main survey waves with active coastal users:

Wave 1: Baseline choices and trips
In the first wave, respondents reported their coastal recreation behaviour and completed a beach-choice experiment. They chose between bathing sites with different features, such as distance, designated bathing status, lifeguards, weather information and water-quality monitoring. This allowed the team to estimate how much people value different site attributes, including access to water-quality monitoring.

Wave 2: Risk education and repeated choices:
In the second wave, respondents were randomly assigned to different information groups. Some received minimal information, while others received more detailed information about pathogens, exposure pathways, symptoms, vulnerable groups and prevention. Respondents then completed a knowledge quiz and repeated the beach-choice experiment. This made it possible to test whether risk education changed knowledge, choices and preferences for monitored bathing sites.

Wave 3: Longer-term policy support and reported trips:
About one year later, respondents completed a policy-choice experiment. They chose between public programmes with different levels of infection risk reduction, monitoring frequency and household cost. They also reported their trips again. This allowed the team to examine whether earlier risk education had longer-term effects on policy support, monetary valuation and recreation behaviour.

Results

• The study shows that people learned from the risk information. Respondents who received more detailed pathogen-risk information had higher objective knowledge and higher self-rated knowledge shortly after the information treatment.
• People also changed how they made choices. When more frequent monitoring was available, respondents were willing to travel further to choose better-monitored bathing sites. This shows that timely information about water quality can directly affect site choice.
• Risk education also changed the value people placed on information. Respondents who received detailed pathogen-risk information attached greater importance to water-quality monitoring than those who received minimal information. In other words, education about invisible health risks made timely monitoring information more valuable.
• People were willing to travel further for safer and better-informed bathing sites. On average, they were willing to travel around 4.7 km further to visit a designated bathing site with a lifeguard and around 3.3 km further for a designated bathing site without a lifeguard.
• They also valued more frequent monitoring. Respondents were willing to travel around 2.0 km further for bathing sites tested every two weeks, 2.8 km further for weekly testing, 3.3 km further for testing every two days, and 3.6 km further for daily testing.
• The policy-choice experiment showed that people were willing to pay for lower infection risks and for more frequent water-quality monitoring. This gives public authorities monetary estimates of the value that users, and potentially the wider public, place on mitigation and adaptation policies.
• The travel-cost evidence adds a behavioural dimension. It suggests that information is associated with changes in reported recreation demand and trip behaviour, although these results should be interpreted carefully and not overclaimed as final welfare estimates.

Overall, the evidence suggests that information changes what people know, where they say they would choose to go, how they value monitoring and risk reduction, what policies they support, and at least some aspects of recreation behaviour.

What does this mean for policy?

Information should be treated as an adaptation tool, but not as a substitute for cleaner water or better infrastructure.

• Risk education and timely risk information should be considered separately. Campaigns and public-health messages can increase knowledge and change how people think about risks. Monitoring, warnings, forecasts and apps provide current risk signals that people can use when making decisions.
• Both types of information have economic value. People value access to monitoring and risk information, and they are willing to pay for policies that reduce infection risk and improve monitoring. These values can be used in cost-benefit analysis.
• Cost-benefit analysis of bathing-water policies should include communication. If information changes knowledge, preferences, behaviour and policy support, it also changes welfare-relevant inputs for appraisal.
• Authorities should not rely on awareness alone. Communication should be clear, trusted, timely and linked to practical decisions, such as where to swim, when to avoid bathing, or how vulnerable users can reduce exposure.
• Information is most useful as part of a wider adaptation package. The strongest approach is likely to combine education, monitoring, warnings, forecasting, disclosure systems and mitigation of water-quality problems.

Future research

The next step is to better understand who benefits most from information. Further analysis should examine whether people with pre-existing health conditions, older adults, families with children or high-exposure users learn more, update their preferences more strongly, or change behaviour differently.

More work is also needed to connect the Polish case-study evidence with other BlueAdapt work on forecasting, warning systems, apps, health-risk modelling and cost-benefit analysis.