Upper Horizons Threatens the Neretva River

Estimated reading time: 5 minutes · Last updated: 21 October 2026

The Upper Horizons hydropower scheme would redirect large volumes of karst water away from the Neretva basin, putting the river’s ecology, wetlands and downstream livelihoods at risk. Environmental groups and local residents warn the project could remove about two billion cubic metres of water a year from the Neretva’s catchment, altering salt intrusion at the delta and drying peat in Hutovo Blato. The reporting, based on field visits and interviews with residents and scientists, was as first reported by BIRN. The first plant, Dabar, is almost complete in Republika Srpska; planners envisage two more plants that together will feed the older Lower Horizons system downstream.

Fishing has been in my family for four generations,

Miroslav Dugandzic, Komin fisherman

How Upper Horizons would shift Neretva’s water

Upper Horizons is a cascade of three new plants—Dabar, Nevesinje and Bileca—designed to capture karst water in eastern Herzegovina and run it into the Trebisnjica basin to feed the older Lower Horizons plants. The scheme’s core mechanism is diversion: water collected in wet months will be stored and released through tunnels and reservoirs so downstream turbines in the Trebisnjica system can generate year‑round.

The system ties new reservoirs to an existing network. Lower Horizons—the mid‑20th century plants Trebinje I and II, Capljina and Dubrovnik—already draw heavily on the Neretva basin: Lower Horizons already takes an estimated four billion cubic metres a year from the Neretva basin. Project engineers say that linking the new Upper Horizons reservoirs to that network increases predictability of supply but also concentrates where the basin’s water ends up.

Ecological costs: wetlands, endemic fish and carbon stores

Hutovo Blato, a Ramsar site and peat bog fed by Neretva springs, acts as a natural flood buffer and a long‑term carbon sink. Irene Rozic, the park’s director, told BIRN that Hutovo Blato “stores more carbon than all the forests in Bosnia and Herzegovina,” but that parts of the park already dry in autumn because of past diversions and could dry further if Upper Horizons reduces incoming water.

The karst poljes that supply the Neretva basin are also hotspots for cave and endemic species. Ichthyologist Matej Vucic found juvenile Telestes dabar in May 2025 after an eight‑year absence, but he warns that those fish, plus Telestes metohiensis and Delminichthys ghetaldii, rely on regular surface flooding to reproduce. If tunnels intercept the seasonal floods, those mating cycles and the subterranean habitats they depend on could be interrupted or lost.

Politics, permits and local consent

Upper Horizons is being built inside Republika Srpska, but its impacts cross entity borders within Bosnia and Herzegovina and reach into Croatia, which has filed complaints under the Espoo Convention. That cross‑border footprint makes mitigation politically sensitive: the Federation government sought an inter‑entity commission to coordinate water management but the motion failed to pass.

Local resistance is growing. On May 25, 2026, landowners near Nevesinje were called to a meeting where officials offered about 3.5 euros per square metre for plots in the planned Nevesinje reservoir; attendees refused the offer, according to local journalist Miljan Kovac. Civil society groups such as Foundation Atelier for Community Transformation (ACT) have staged protests and publicity stunts in Mostar to raise awareness of cultural as well as environmental impacts.

Money on the table—and stalled payments

Hidroelektrana Dabar d.o.o., a subsidiary of state utility Elektroprivreda Republike Srpske, is the project promoter. China Energy Gezhouba Group is the main contractor and the project is backed by a 190‑million‑euro loan from China’s Exim Bank, guaranteed by Republika Srpska. Local reporting says Exim Bank stopped disbursing in August 2025 and that Gezhouba temporarily reduced its workforce when diversion works lagged.

Official transparency is limited: Republika Srpska has renewed Dabar permits on the basis of a 2012 impact study and, according to Bankwatch, has refused to disclose the loan contract and construction contract with Gezhouba. The combination of disclosed funding, paused disbursements and withheld contracts leaves the project’s timetable and costs uncertain.

How the case for and against the project could unfold

The bottom line

Upper Horizons links new reservoirs and tunnels in eastern Herzegovina to an existing mid‑century hydropower network, promising steadier generation while shifting where the basin’s water flows. That trade‑off matters because scientific and local witnesses say the Neretva’s delta and Hutovo Blato already show the effects of past diversions: peat drying, species loss and salt intrusion. With legal challenges pending under the Bern and Espoo conventions, suspended disbursements reported in 2025 and local resistance to expropriation, the project’s environmental and social costs are likely to shape its timetable and final design.

What to watch

• Watch for the Dabar plant connection to the grid; the plant’s director said it should be connected in 2028.
• Watch for the outcome of Croatia’s Espoo Convention complaint; no date has been set.
• Watch for any official disclosure of the Exim Bank loan contract or the construction contract with China Energy Gezhouba Group; no date has been set.