Plitvice, natural treasure becomes victim of its own success

How mass-tourism pressures wastewater infrastructures and affects groundwater

Waterfalls as far as the eyes can see, surrounded by a lush, green environment, cascade into 16 crystal clear and interconnected lakes. The emerald green of this pristine water creates a beautiful colour palette with the dense forest in the backdrop. Looking at the natural beauty of Plitvice Lakes National Park, it is easy to grasp how this captivating site attracts more tourists every year. In 2022 alone, about 1.9 million people found their way to this park In Croatia. Ironically, these nature-loving visitors are leaving an increasingly large mark on the nature they so much adore.

Plitvice national park waterfall scenery
Plitvice national park waterfall scenery

‘Park of 16 lakes’ has a 17th lake

Moving away from these 16 lakes that make up the Plitvice Lakes, but still within the national park, Mayor Ante Kovač takes a WDR journalist into the forest. “Welcome to the 17th lake!”, he says when approaching a pool of wastewater. The narrator of the WDR documentary calls the stench ‘bestial’ while showing the illegal and unidentified drainpipe discharging wastewater into the sinkhole. 

“This is the dark side of Plitvice”, concludes Kovač the situation fittingly while gazing over the murky grey water in front of him.

WDR Documentary

He then continues to explain what he calls the ‘tragicomic paradox’ that the national park and water authorities are currently facing. “The sludge is coming from the hotels of the National Park”, he starts. “So, the biggest protector of the park is at the same time the biggest polluter.”

UNESCO heritage status at risk

The state of the national park and the quality of its waters also became an increasing concern for UNESCO, who in 1979 had included Plitvice on its famous list of World Heritage Sites. In 2017, UNESCO sent a mission to the park to evaluate the impacts of tourism, water extraction and pollution of both groundwater and surface water. The report that this visit yielded and monitored the construction of tourist lodging within the park mentioned “rapid increase in the number of issued permits is noticeable” and “a considerable number of reports of suspected illegal construction had been submitted to the State construction inspectors”. As a result of this rapid increase, the mission report noted that “growing water demand due to an increasing number of visitors and facilities, consequently increasing wastewater disposal, and a high risk of water pollution pose serious threats to the sensitive hydrological system of the property.” The report concluded with a very clear message for the responsible authorities:

If no substantial progress in the implementation of the World Heritage Committee’s requests and of the recommendations of the mission can be achieved by 2018 and in view of the current and potential impact from the significant and unsustainable expansion of tourism facilities and excessive number of visitors on the property and its OUV, the mission recommends that the World Heritage Committee consider inscription of the property in the List of World Heritage in Danger at its 42nd session in 2018.”

World Heritage Committee, January 2017

That would’ve been the second time that the heritage site ended up on UNESCO’s danger list, with the first one being during the period of war in the 1990’s. This urged some immediate actions, described later in this story, but first, how did the situation even reach this stage of urgency?

Long history of Plitvice

Plitvice has a long history. Not only because it took nature over 16 million years to create its unique formation, but it also played a crucial role in (relatively) more recent history. It formed a natural border between the Habsburg monarchy and the Ottoman empire. Later, in 1928, there was already some attempts to preserve the lakes. That year it was first proclaimed a national park. However, this status only lasted one year, after which it took until 1949 before it permanently become a national park.

Tourism increased, wastewater facilities did not

The Yugoslav wars changed a lot, also for the Plitvice Lakes national park that was now located in Croatia. Until that moment, the national park was responsible for all communal infrastructure, including transport, lodging and also (waste)water. After independence, new Croatian legislation demanded that wastewater management would become the responsibility of water companies. However, Plitvice Lakes national park remained an exception.  

This all-encompassing logistical task became increasing challenging as more and more tourists discovered this natural treasure. Particularly the wastewater management started to become an issue. The park did have a wastewater treatment plant. However, this one stemmed from the late 1940’s, when there were little to no tourists visiting the park. The plant, therefore, managed to meet the demand for decades. The touristic boom, starting in the late 90’s and exponentially developing into the new millennium, has been building up the pressure on the existing structure.

Besides this wastewater treatment plant concentrated around the lakes area, there are many unconnected latrines throughout other parts of the national park. The wastewater those latrines produce, is often simply released in pit caves and pit holes. This has not been an uncommon practice, but with the increase of visitors, and thereby faecal waste, this has been increasingly adding up to the wastewater problem.

National Park Plitvička Jezera, by: Kolega P
National Park Plitvička Jezera, by: Kolega P

Groundwater problem reaching the surface

The city of Bihać, in the country of Bosnia & Herzegovina, is simultaneously facing a challenge as well. A water quality challenge to be more precise. This city, of over 61,000 inhabitants, relies for its water supply primarily on the Klokot spring, connected to the Plitvice Lakes national park through their shared groundwater catchment. In 2020, a study was done to research the water quality and it concluded that “many of the samples analyzed in the last 5 years show tendency of water quality deterioration at the spring itself”. This was due to significant frequent presence of Coliform, E. coli and Enterococcus bacteria. All three are indicators for the presence of faecal material in water. Faecal contamination of water is linked to diseases like cholera, diarrhea, dysentery, hepatitis A, typhoid and polio. Needless to say, the report concludes that raw water from the Klokot spring “does not conform to the sanitary and epidemiological requirements”.

Una in Bihać
Una in Bihać

Transboundary waters

Further down the same report, it also becomes apparent that the sanitation issues in the Croatian national park and the groundwater quality problems in Bosnia & Herzegovina are actually linked.  

“One factor which significantly contributes to the deterioration of the microbiological quality of water at the Klokot spring is a significant increase of human activity in the Klokot spring catchment area, especially through the intensification of tourist visits to Plitvice Lakes National Park, as visible from the rapidly growing number of nights spent in that area in the last 5 years.”

Report on Spring cross-border sanitary protection zones Klokot (Bihać), 2020 

From a groundwater perspective, this area underlying the two neighbouring countries is quite special, because it is a ‘karstic’ area. Groundwater has a slightly different behaviour in these aquifers comprised of rock and limestone than it would have in sand or clay environments. While groundwater flows more slowly through clay layers, the cracks and openings in karst aquifers allow the groundwater to travel faster and also further. This is how the situation in Plitvice National Park can have transboundary impacts in a city 20km away, on the other side of the state border. The water, accompanied by bacteria, enters the Rastovače karstic hole, Korenica sinkhole, and at Prijeboj stream sinkhole on one side and then comes to the surface through a karstic Klokot spring on the other side.    

Catching up with infrastructure

The concerns raised by UNESCO as well as the water quality studies carried out, have resulted in some changes, both on a governance and a technical level. Plitvice Lakes N.P. no long manages its own wastewater infrastructure and the water companies are now responsible. Arguably the biggest change is the construction of a second wastewater treatment plant to catch up with the increased demand. Although infrastructural solutions take time and so do their positive impacts on ecosystems. The park has also developed a renewed housing planification and long-term management plan.

There is also increased awareness about the transboundary nature of the catchment area (approx. 90% Croatia/10% BiH) and the impacts of pollution on groundwater quality. To help this process, a feasibility study was conducted on establishing transboundary cooperation between the Plitvice Lakes N.P. in Croatia and the Una N.P. in Bosnia & Herzegovina. In addition, a World Bank-funded study in 2020 looked into the possibility of establishing spring cross-border sanitary protection zones for the Klokot and Privilica sources.

Still room for improvement

Such transboundary cooperation, however, remains highly politicized and thereby complex to actually implement. “It is important to not only think about what happens within state borders but also within natural borders, of groundwater catchments for example”, says Dženeta Hodžić, Research Scientist at ISOE - Institute for Social-Ecological Research, who is conducting ethnographic research on underlying cultural dimensions of groundwater extraction practices. 

“There are many uncertainties when it comes to our understanding and knowledge of groundwater in karst landscapes, and most of Croatia’s groundwater catchments are transboundary not only with Bosnia-Herzegovina but also with Slovenia and Serbia.”

Dženeta Hodžić, Research Scientist - ISOE

According to her, this transboundary case of Plitvice Lakes N.P. shows that drinking water should be in the interest of everyone. “The transboundary groundwater catchment of Klokot spring in Bosnia-Herzegovina and Croatia is one example where the larger part of the catchment lies in Croatia. Hence, pollution there disproportionately affects the springs in Bosnia-Herzegovina next to their own. However, there are many examples where the situation is reversed, where the larger part of the groundwater catchment lies in Bosnia-Herzegovina and pollution there disproportionately impacts springs in Croatia.”

The referenced media source is missing and needs to be re-embedded.
Plitvička Jezera, by Josephine S.

Also, the construction of a second treatment plant should not be seen as the ‘Egg of Columbus’, solving all underlying issues at once. “They have chosen a technical fix for a problem that is also social”, says Dženeta Hodžić. “The ecological and infrastructural issue was addressed by installing a new wastewater treatment plant that has a higher filtration level. The mass tourism, the core of the concerns expressed by local residents in their protests about the ‘17th lake’ is still left unresolved.” Some attempts were done to promote a different kind of tourism, with a bigger focus on hike in other parts of the park to relieve the pressure on the lakes area. Not an easy task, because the lake remains the major attraction, like the Eiffel tower for Paris and the Colosseum for Rome.

Hodžić, whose research is part of the REGULATE project, sees that there is also still room for improvement when it comes to addressing infrastructure development as cultural dimensions. “Municipal infrastructure in particular is often a matter of concern in countries with post-socialist legacy like Croatia”, Hodžić explains. “It is important to understand the infrastructural history in domains of water supply and wastewater treatment. It tells us a lot about the social and cultural norms inscribed in the infrastructure: from the organization of community life to the relation to natural resources such as water.”

More sustainable tourism

“As tourists, we can always ask ourselves: Where does the local drinking water come from? And where does the water I use go to?”, says Hodžić when asked what tourists visiting the Plitvice Lakes could do themselves to improve the situation. “Drinking water and waste water is an issue that concerns everyone, no matter if we’re staying at hotels, private accommodations or camp sites.”

She noticed that most tourists do not know that the drinking water in the Plitvice Lakes N.P. is in fact provided by one of the 16 lakes. “Likewise, tourists often lack awareness for their local ecological impact. There are huge repositories of pamphlets about the local history of the national park, the development of its hotels etc. But most of the tourists still equate the park with the lakes. Sometimes tourists even come in search for waterfalls that are located in an entirely different national park in Croatia.”

Another recommendation is to simply talk to locals who live in the national park or in close proximity. “Ask them about their lives in the park, their concerns, their lives outside of tourist season. From experience I can say that they often have the more interesting stories to tell!”

Simply by addressing concerns while visiting the park can actually already go a long way. 

“We can make infrastructural concerns part of our touristic activities. The economic driver of tourists’ interests cannot be underestimated, particularly in sites of mass tourism. We can engage in conversations about infrastructure with our accommodation hosts, with the park rangers and tour guides, with service workers in the hotels and restaurants. The third or fourth time a tourist asks about infrastructure, it will start to have a ripple effect."

Plitvice Lakes National Park, by: Miroslav Vajdic
Plitvice Lakes National Park, by: Miroslav Vajdic

World Toilet Day 2023

This story is written in light of World Toilet Day 2023. This day is all about accelerating change by doing whatever you can. Take action today, learn about the issues and share the campaign with your networks. 

World Toilet Day 2023
World Toilet Day 2023