RECONECT’s new European Collaborator in Bosnia and Herzegovina
The RECONECT B&H Collaborator is affected by riverine and flash floods and landslides. Frequent floods, great damage, high recovery costs in the past indicate the need to improve the flood protection system and create conditions for better flood risk management. This is where we need RECONECT.
Authors: Tamara Sudar, MSc Civil Engineer, member of the University of Belgrade (UNBELGR) team; Prof. Jasna Plavšić, PhD Civil Engineer, member of the University of Belgrade (UNBELGR) team.
The main river basins in Bosnia and Herzegovina drain towards the Black Sea and Adriatic basins. The Vrbas drains to the Black Sea basin and is one of the most important right tributaries of the Sava. The Vrbanja tributary stands out in the Vrbas basin for its impact on flood hazards and risks. In the past 10–15 years, the Vrbanja has a dominant impact in the formation of increased trends of flood flows in its own basin but also on the river Vrbas in the City of Banja Luka, where the confluence of these rivers is located. Banja Luka is the second largest city in B&H and the largest city in the Republika Srpska (one of the B&H entities).
The Vrbanja basin is located in the Republika Srpska, in the central part of Bosnia and Herzegovina (Figure 1), covering an area of 804 km2. The relief changes from mountainous in the upper course to lowland in the lower course, with the difference in altitude of about 1,500m.
The topography of the Vrbanja basin and the dominant anthropogenic impacts, where the most important is the reduction of forest areas, have influenced an increase in floods in urban areas. Parts of the basin are subject to flash floods characterized by short duration, high flow velocities, and massive movement of sediments. The river course is partially regulated in urban areas.
Extremely unfavourable flood flow regimes, the frequency of floods, and the current level of urban development along the Vrbas, impose the application of measures to control flood runoff in the upper and middle parts of the basin. Since the Vrbanja sub-basin has a significant contribution to the formation of flood waves in the City of Banja Luka which is extremely vulnerable due to flood risks, especially during the superposition of the flood waves of the Vrbas and Vrbanja, this sub-basin was selected as a focal area for improving flood protection by applying nature-based solutions.
Water-related hazards affecting the area
The Vrbanja basin has a population of about 40,000 in the municipalities of Kotor Varos and Celinac. A part of the City of Banja Luka with the population of about 70,000 is also under the influence of the flood flows of the Vrbanja.
Extreme floods occurred in the Vrbas basin in December 2010 (Figure 2) and May 2014 and lasted for two to three days. Significant flooding is registered in the municipalities of Celinac and Kotor Varos, where the Vrbanja spills over the banks in the centre, while floods of much wider extent also occur in the City of Banja Luka.
Catastrophic floods affected the Sava basin in Serbia, Bosnia and Herzegovina, and Croatia in May 2014. The direct and indirect damage for the Vrbas basin were estimated and the result indicated that most of the damage caused by the tributaries was actually in the Vrbanja basin.
NBS in the area before RECONECT
Given that significant floods by the Vrbanja were recorded only in 2010 and 2014, more intensive planning and construction of structural flood protection measures began after 2014. Due to the significant increase in runoff from the basin but also significant erosion and flash flooding, it is necessary to plan for erosion and flash flood control measures. The Flood Risk Management Plan (UNDP B&H 2019) proposed erosion control and bioengineering measures for the Vrbanja basin with the aim to partially slow down runoff from the basin. These measures are planned only to a limited extent but they can easily be incorporated into NBS measures.
Why joining RECONECT?
In B&H the NBS have been scarcely addressed. The potential for their systematic implementation as standalone measures or in a combination with the traditional engineering measures (referred to as hybrid solutions) is still underdeveloped and requires further investigations. While the common practice is to optimise the risk reduction measures only against a single goal (i.e., mitigate floods or droughts), the co-benefits for, for example, biodiversity and/or human well-being are rarely considered. As a rule, data is scarcely available and the knowledge and awareness of people and institutions in the region is usually insufficient. Current flood protection systems in some areas are either not sufficient or not existent, and their improvement in the future could be built on NBS. This requires an integrated water management approach combined with the holistic perspective on possible benefits for nature and people, which is currently not being practiced. This is where we could use RECONECT’s help.
What is RECONECT currently doing in the area?
The selection, design and implementation of NBS with the participation of stakeholders from different levels is crucial. RECONECT’s stakeholder mapping methodology has helped to intensify links with local key stakeholders. A good relationship with them is very important for understanding the local contexts in which NBSs would be implemented.
Bosnia and Herzegovina has a complex administrative structure and consists of two entities (the Republika Srpska and the Federation of B&H) and the Brcko District. Flood risk management is carried out in accordance with the EU Floods Directive 2007/60/EC, which is implemented in the entities’ Water Acts. Flood management is the responsibility of the entities, and coordination and communication with international organizations (EU, EC, WB, etc.) is carried out at the level of B&H. The implementation of NBS must be focused to and implemented within three key sectors: agriculture, forestry and water management. These three sectors are united within the relevant Ministry of the Republika Srpska. It is necessary to include support and cooperation with spatial planning at the level of the Republika Srpska and local communities, other sectors and stakeholders, primarily the scientific community, other Ministries and also non-governmental organizations.
RECONECT’s stakeholder survey and the multi-criteria analysis of stakeholders’ interests helped to gain a better view of local stakeholder’s expectations and preferences about the benefits and co-benefits of NBSs in the basin. Prior to the survey, a virtual introductory meeting was organized with the key stakeholders in the Vrbanja basin and RECONECT representatives in order to inform the stakeholders about the project goals and introduce them to NBS measures. The response was surprisingly positive and most of those present showed interest in hearing more about the next steps, as well as the results of the analysis. Most of the stakeholders gave the advantage to the goals related to water quality and human well-being, followed by the main risks in the area — floods and landslides. The result of the survey was also a broader list of NBSs that are suitable for the Vrbanja basin, prioritized according to the value that stakeholders put on different goals. The virtual meeting and the survey were key in initiating the process of co-creation.
Nature-based solutions are relatively new in B&H and encounter certain barriers to their implementation. The first important barrier is the lack of legislation that defines the planning and implementation of NBSs. However, after the launch of the project in the Vrbanja basin, there are improvements in making NBS binding in strategic documents of the water sector (Integrated Water Management Strategies, Flood Risk Management Plans) and also legal norms. Another key barrier is land ownership. In order to implement certain solutions, local authorities would have to deal with hundreds of landowners who do not want to leave their properties, which makes the process long and frustrating, and therefore, it is common practice to avoid interfering in property relations.
Due to the economic situation of the state, the possibilities of financing are very modest. However, taking into account the need to strengthen the basin capacity through the coordination of key sectors, the RS Ministry of Agriculture, Forestry and Water Management expressed great interest in participating in this project. The Ministries dealing with ecology expressed similar interest. These are encouraging signals! The project would be carried out with the active participation of the scientific community, which understands the problems facing this area and which gives full support to this project.
The Vrbanja basin joined the RECONECT project as a European Collaborator with the goal of exchanging the experience and knowledge with the project’s consortium, while having the support of international experts and learning from the multidisciplinary RECONECT team. There are numerous basins in B&H that have the same or similar characteristics and multiple risks as the Vrbanja basin. This project is extremely useful as it could be used a pilot to develop similar projects throughout B&H. After NBS are implemented in full capacity and begin to give the expected results, it is possible to start optimizing structural flood protection measures and their rationalization.