Brussels, 20 November 2025 — ETIP HYDROPOWER released last thursday 20th November three new White Papers dedicated to biodiversity, focusing on some of the most relevant interactions between hydropower operations and river ecosystems: fish mobility, environmental flows and hydropeaking, and sediment dynamics.

Developed by experts from Working Group 2, the series compiles state-of-the-art knowledge, European practices, and recommendations to support hydropower operators, researchers, and policy makers in advancing environmentally sustainable hydropower.

White Paper on Enabling Fish Mobility at Hydropower Plants

This paper highlights the role of fish migration in maintaining river connectivity and biodiversity. It reviews current technologies and solutions to improve upstream and downstream passage, including nature-like and technical fishways, fish lifts, bypass systems, behavioural guidance structures, and fish-friendly turbines.

It stresses the need for:

• Comprehensive site-specific assessments combining hydraulic and biological perspectives. 
• Clear criteria and performance standards for both upstream and downstream measures. 
• Integration of monitoring and adaptive management to ensure effectiveness over time.
• The document also identifies research gaps in areas such as fish behaviour, cumulative impacts, and the performance of innovative downstream solutions.

Download the White Paper on Fish Mobility

White Paper on Environmental Flows and Hydropeaking

This paper explores how environmental flows (E-flows) and hydropeaking management can reconcile river ecosystem needs with flexible hydropower production. It summarises methodologies applied across Europe (from hydrological and habitat-based to integrative approaches) and provides guidance for their implementation.

Key recommendations include:

• Developing robust, transparent, and adaptive E-flow methods grounded in ecological evidence. 
• Implementing long-term monitoring of both hydrological and biological indicators. 
• Considering hydropeaking mitigation measures, such as ramping rate control, re-regulation basins, and coordinated operation of plants.
• The paper calls for harmonised European approaches and the integration of E-flow considerations in hydropower licensing and policy frameworks.

Download the White Paper on E-flow and Hydropeaking

White Paper on Sediment Dynamics

Sediment transport is essential to river morphology, habitats, and infrastructure resilience. This White Paper explains how hydropower operations alter sediment continuity and outlines a comprehensive set of management measures to address it: such as sediment flushing, sluicing, venting, bypassing, replenishment, and dredging.

Its main messages include:

• The importance of catchment-scale and multi-stakeholder planning for sediment management. 
• Promoting integrated monitoring systems to track sediment fluxes and ecological effects. 
• Encouraging research and innovation in emerging solutions such as sediment venting and robotic dredging.
• By re-establishing sediment continuity, these practices can deliver joint benefits for ecosystems and reservoir performance.

Download the White Paper on Sediment Dynamics

Together, the three White Papers illustrate practical ways to achieve “win-win” solutions between hydropower operation and river ecology. They provide knowledge that supports the objectives of the EU Water Framework Directive, the Nature Restoration Regulation, and the Renewable Energy Directive (RED III), contributing to Europe’s broader goals for a climate-resilient and nature-positive energy transition.