As Central Asia’s power demand accelerates, the question is not only how much hydropower remains, but where and how it can be developed responsibly.

This blog from BOKU University features Hydro4U work from the regional scale to local biodiversity assessments and how fish interact with river hydraulics.

Read on to find out about how we leveraged open-access data to assess the sustainable hydropower potential in Central Asia and what exciting work Hydro4U ecologists have been doing at the Shakhimardan demonstration site.

The 92‑TWh question: Ecosystem‑aware hydropower pathways for Central Asia

By 2050, electricity demand in Central Asia could more than double. Ambitious hydropower plans are emerging, but the real challenge is designing projects that balance energy needs with ecosystem integrity and geohazard risks.

Until now there has been no consistent, region‑wide view of where hydropower can be expanded without unacceptable ecological costs or undue exposure to geophysical risk. Our new study delivers that picture. We present a reproducible, open‑access framework for assessing hydropower potential at the scale of individual reaches, moving from what is physically possible to what is environmentally and geophysically sustainable, thereby offering a regionally consistent baseline for strategic planning.

The headline finding is scale: starting from about 703 TWh per year of theoretical potential, successive filters for technical feasibility, existing hydropower use, geohazards and ecology reduce the total to 92 TWh per year of sustainable potential – roughly 13% of the gross resource. This remaining opportunity is not evenly distributed. Nearly four‑fifths lies in the upstream countries of Tajikistan and Kyrgyzstan, with smaller but meaningful shares in Uzbekistan and Kazakhstan, and almost none in Turkmenistan. Ecological sensitivity is widespread. More than half of the remaining opportunities intersect sensitive areas; yet only a minority fall within strict no‑go zones that warrant exclusion. In the mountains, landslide and seismic risks further narrow options, especially where they coincide.

These patterns have clear policy implications. Because so much of the resource sits upstream, cross‑border power trade and coordinated, basin‑scale planning become critical to share benefits and manage trade‑offs with irrigation and other water uses. The structure of the opportunity also differs by country. In Kyrgyzstan, many viable sites are on small to medium tributaries, opening space for more decentralized projects that can strengthen resilience and rural energy access. In Tajikistan and Uzbekistan, opportunities cluster on medium‑sized rivers, where careful siting and modern mitigation will be essential to maintain connectivity and biodiversity. Across the region, early screening for ecological and hazard conflicts can shorten permitting, reduce the risk of stranded assets, and help align Sustainable Development Goal 7 (clean energy) with SDG 15 (life on land and freshwater).

The BOKU team is currently making the high‑resolution maps openly available and integrating them into an interactive Hydro4U decision‑support tool, HydroPlan-CA, which will be published online in the next months.

Further studies are underway to enhance knowledge on freshwater biodiversity patterns in Central Asia, improving data availability in a still data-deficient area. Moving from regional to site-specific assessments, ongoing ecoydraulics studies, such as those at the Shakhimardan and At-Bashy demonstration sites, help guide the implementation of ecological mitigation measures at hydropower plants, including up- and downstream migration corridors and environmental flows.

Field sampling throwback

In spring 2025, we traveled to our study site in Uzbekistan, the Shakhimardan exclave, to work on post-implementation monitoring and fish ecohydraulics in the context of the Hydro4U Francis Container Power Solution.

Together, we carried out extensive fieldwork, including fish and macroinvertebrate surveys, hydraulic measurements, fish tagging, Passive Integrated Transponders (PIT) antenna employment, and tracking of radio-tagged fish. We also collaborated with the RETERO project to conduct in-situ experiments to better understand the downstream migration of snow trout at a hydropower weir.

Preliminary results of the quantitative assessment of macroinvertebrates in the Shakhimardan River Basin were presented at the XVth All-Russian Trichopterological and Xth All-Russian with International Participation Symposium on Amphibiotic and Aquatic Insects. Other results were presented in September 2025 at the 3rd International Conference on Sustainability in Hydropower in Vienna, Austria.

Key talks included:

• Radio telemetry on snowtrout (Schizothorax eurycephalus) unravels seasonal migrations and habitat use with implications for hydropower development in Central Asia
• Hydraulic Optimization of the Bypass Entrance Design for Downstream Fish Migration: Insights from Laboratory and Field Studies
• Developing a System Dynamics Model to Evaluate Hydropower-Focused Power Development Policies for Achieving SDG 7 in Central Asia by 2050

The summaries of these works can be found in the Conference Proceedings.

Author and Picture credits: Daniel S. Hayes, BOKU University