River in focus: Neretva

Country: Bosnia and Herzegovina

Local partners: CZZS, ACT, Aarhus Center

Project goal: To defend the Neretva and her tributaries from further hydropower expansion, secure a strict protection status for its remaining wild sections, and end destructive hydropeaking practices at the Ulog hydropower plant.

Background

The Neretva River, stretching over 230 kilometres from the Dinaric Alps in Bosnia and Herzegovina to its delta on the Adriatic coast of Croatia, is one of the most striking and ecologically valuable rivers in the Balkans. Its emerald-green waters cut through deep canyons, nourish fertile valleys, and sustain a rich mosaic of habitats from alpine meadows and karst springs to Mediterranean wetlands.

The upper Neretva is a biodiversity hotspot of global significance. It harbours numerous endemic and/or endangered species, including the white-clawed crayfish or the softmouth trout, one of Europe’s rarest fish. The Softmouth trout occurs only in a handful of Balkan rivers, with the most viable populations found in the Neretva upstream of Konjic. Ironically, this very stretch is now targeted by a series of new dam projects.

Recent fieldwork has confirmed the spawning of softmouth trout in the Ljuta, one of Neretva’s pristine tributaries, where eDNA samples have again verified its presence—powerful evidence of the river’s outstanding ecological value and the need for its protection.

Ongoing threats

The Neretva river system is among the most threatened in Europe. All remaining free-flowing stretches and every single tributary face the threat of hydropower development. More than 50 planned dams, both large and small, endanger the integrity of the entire river basin.

• Despite years of resistance, the Ulog Hydropower Plant in the upper Neretva was completed and began operation in 2025, causing significant environmental harm. It has already triggered a major ecological disaster: a mass fish die-off during one of the first flush operations in September 2025, exposing the dangers of poor management and weak environmental oversight.
• The massive Upper Horizons project, the largest dam system proposed in Europe, would divert major karstic tributaries away from the Neretva downstream of Mostar, causing an ecological catastrophe in the poljes (periodically flooded karst fields). Several fish species are expected to go extinct.
• Dozens of small hydropower projects threaten to block tributaries that are home to endangered fish and aquatic invertebrates.
• Illegal logging and unsustainable land use in the upper catchment further degrade habitats, increasing erosion and sedimentation risks.

If realised, these projects would fragment one of Europe’s last connected river systems, destroying critical habitats and erasing centuries-old ecological and cultural continuity.

How we are taking action

The Save the Blue Heart of Europe campaign, together with our local partners as well as other local stakeholders such as fishing organisations, works to protect the Neretva’s last wild stretches and secure its long-term conservation.

Our actions include:

• Scientific advocacy: Supporting biological research, including fish monitoring and eDNA sampling, to build a solid evidence base for conservation and challenge flawed Environmental Impact Assessments.
• Legal interventions: Submitting expert analyses and legal complaints to ensure compliance with national and EU law.
• Awareness and outreach: Using media, photography, and field reports to expose environmental violations and rally international attention.
• Community engagement: Collaborating with fishermen, local NGOs, and residents to defend their river.
• Policy advocacy: Engaging decision-makers to secure legal protection and integrate conservation goals into regional development plans.

Supported by Manfred-Hermsen-Stiftung

Related news:

09/2025: Ecocide on the Neretva: Scientists raise alarm after mass fish die-off

05/2024: In search of Softmouth Trout and Huchen

01/2024: Preliminary Report of the Neretva Science Week 2023

11/2023: Protest Against HPP Ulog on the Neretva Held in Konjic

07/2023: Great victory for the citizens of the Neretvica Valley

06/2023: 70 scientists from 17 countries at Neretva Science Week 2023

12/2022:  Bern Convention demands Bosnia-Herzegovina to stop all dam projects on Neretva River

08/2022: Preliminary Report of the Neretva Science Week 2022

07/2022: The Neretva River Science Week 2022: 50 scientists, seven days, one river, one goal