LIBRARY: Introducing the TETHYS4ADRION Pilot Rivers: The Neretva River

The Neretva River is one of the five pilot rivers being monitored as part of the TETHYS4ADRION project. It is the largest karst river in the eastern part of the Adriatic Sea basin and the fifth-largest river flowing into the Mediterranean. The river originates between the slopes of the Zelengora and Lebršnik mountains in Bosnia and Herzegovina (BiH). Its total length is approximately 225 km, of which 22 km flow through Croatia, where it discharges into the Adriatic Sea at Komin, near the Port of Ploče.

The Neretva is considered one of the coldest rivers in the world, primarily due to the high altitude of its source and the heavy snowfall in the region. In the upper course, water temperatures typically reach around 7°C during the summer months. Around the city of Mostar, in the middle course, summer temperatures are usually around 15°C, while further downstream, they often exceed 20°C.

There are more than 30 tributaries to the Neretva. The most notable are the Bregava, Buna, Krupa, Rakitnica, and Trebižat.

The river’s significant hydroelectric potential has led to the construction of four major plants—Jablanica, Grabovica, Salakovac, and Mostar (all in BiH). These facilities are accompanied by large dams and storage reservoirs. The dam of the Jablanica power plant has led to the creation of Jablanica Lake. A fifth large hydroelectric power plant, Rama, was built on the Neretva’s tributary, the Rama River, resulting in the formation of Rama Lake. Both Jablanica and Rama Lakes are attractive destinations for tourism and recreation.

The Neretva Delta has been designated a Ramsar site—an internationally important wetland. The Hutovo Blato wetland (located in BiH, on the territory of the City of Čapljina and City of Stolac) has been protected as a nature park. It provides a rich habitat for a highly diverse fish community and serves as a resting and wintering site for migratory bird populations. Recent scientific studies conducted in the upper part of the Neretva River have confirmed the presence of more than 1,300 animal and plant species, making the Neretva one of the most biodiverse rivers in Europe.
The wetlands around the Neretva serve as natural flood retention areas, absorbing excess water during high flows.

The areas around the Neretva River have been continuously inhabited since prehistoric times, with evidence of human settlement dating back as far as 11,000 B.C. Archaeological remains from the ancient Greeks and Romans are scattered across the area, including fortifications, Roman villas, and mosaics. The most notable site is in the village of Vid, where the remains of the Roman town Narona and the Augusteum temple—built around 10 B.C.—have been discovered.

In modern times, the Neretva River remains a defining feature of the region’s geography and demographics. The majority of the river flows through the Herzegovina-Neretva Canton in BiH, including the cities of Mostar and Konjic. According to the 2013 census, this canton had just over 222,000 inhabitants. In the Croatian part of the lower Neretva, the surrounding area had a total population of approximately 31,250 residents.

The Neretva Delta is the largest and most productive agricultural region along the Croatian coast, with around 40% to 60% of households involved in agricultural production.
Traditional methods of creating arable land involved digging canals and piling the excavated wet soil into raised plots, forming a patchwork of small fields separated by water channels. These channels, called jendeci, give the Delta its distinctive appearance and allowed movement by small wooden boats: the trupa and lađa, used to transport agricultural goods and livestock. These boats remain in use today and are an enduring part of local tradition.

The Neretva River offers many opportunities for nature-based recreation. Particularly popular among enthusiasts is fly fishing.
Tourism along the Neretva River is growing, though still largely driven by local initiatives. Visitors can enjoy boat tours through the wetlands, or explore the river by rafting, kayaking, rowing, kitesurfing, or diving off the Old Bridge in Mostar.

One of the most pressing issues in the Neretva Delta is the uncontrolled disposal of solid municipal waste and the lack of adequate wastewater treatment facilities. During high-water events or snowmelt, large quantities of plastic and mixed waste are washed downstream into the lower Neretva region. Inadequate wastewater treatment leads to water quality degradation and agricultural pollution, which is particularly striking in the river’s lower course. Old mining sites contribute to acid mine drainage, releasing harmful heavy metals like arsenic, cadmium, and lead. While not direct polluters, hydropower plants and dams worsen the situation by disrupting sediment flow, increasing erosion, and trapping litter.

The accumulation of litter is most evident in the lower reaches of the Neretva River, especially near Metković and other urban areas close to the delta. These regions act as natural retention zones where river currents slow down and materials transported from upstream are deposited.

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can under no circumstances be regarded as reflecting the position of the European Union and/or IPA ADRION programme authorities.