By Bunyod Holmatov, Shavkat Kenjabaev, Mohsin Hafeez, Jose Gonzalez Cabrera and Julien Harou
The Central Asia region covering five former Soviet Republics, Kazakhstan, the Kyrgyz Republic, Tajikistan, Turkmenistan, and Uzbekistan, is facing climate change impacts on water resource availability. This region has already witnessed the drying of the Aral Sea Lake, a legacy of past water resource mismanagement. Water resources management in Central Asia is increasingly becoming sensitive as water scarcity increases. The region’s two significant rivers, the Amudarya and Syrdarya, are transboundary rivers, each flowing through four of the five countries, and are heavily managed. Some of the world’s largest water infrastructures are in the region, such as the Rogun and Nurek multipurpose dams and the Karakum irrigation canal. Planners initially built a regional infrastructure system that maximized output for the Soviet Union and resulted in the countries’ interdependence. Water allocation challenges arose between the upstream and downstream countries, driven by competing needs for hydropower and agriculture. In recent years, against climate risks to agriculture and hydropower in the region, Afghanistan’s construction of a Qosh Tepa Canal further threatens the region’s water security.
The success of water resources management in Central Asia will need regional cooperation and policy harmonization across borders. This process can be aided by planning tools that quantify water availability and help identify synergies achievable by future water interventions (like new policies or infrastructure). While existing institutional structures, like the Interstate Commission for Water Coordination (ICWC) and regional agreements, serve as frameworks for cooperation, challenges related to intersectoral sharing of water, equitable distribution and climate change persist.
The Chirchik River Pywr model
Within the CGIAR’s Nexus Gains Initiative, the International Water Management Institute (IWMI) and its research partners have worked with Central Asian institutions since 2022 to develop a water resources system model of a transboundary river basin in the region. The river basin selected for the study was the Chirchik River Basin, a small transboundary tributary of the larger Syrdarya River shared between Kazakhstan and Uzbekistan. The Chirchik River sub-basin was chosen for Pywr modeling considering the data availability, complex water resource management, and the juxtaposition of abundant resources with high projected demand from diverse sectors, including Tashkent’s industrial facilities. This necessitates analysis of water allocation and the interplay between various uses within the intestate Syr Darya basin management context.
The modeling framework used to build the Chirchik model is Pywr, an open-source water resources system simulation framework co-developed by a community of water practitioners, including the University of Manchester (UoM). Open-source means the modeling framework’s computer code is publicly available, transparent and owned by all. The model simulates multi-sector water availability and use throughout the system and includes the interactions and linkages between water, hydropower, irrigation and environmental needs. By tracking water management (water allocation and infrastructure operation) decisions, their impacts and benefits, the tool helps understand the current water system and evaluate future interventions.
The model was built, shared and run via an online user-interface to facilitate joint working. The Scientific-Information Center of the International Centre for Water Cooperation (SIC ICWC) coproduced the model with the IWMI-UoM team. The main tasks were to jointly setup and calibrate the model to increase the likelihood that it accurately represented water resources in the basin. The goal was to assess Pywr’s appropriateness, kick-start the collaboration and build a new community of practice.
From 2023, online and in-person training sessions were organized involving SIC ICWC and other stakeholders from national academic institutions to equip participants with skills to develop, use and adapt the model. The model and scenario results have been shown at various events, sparking stakeholder interest.
SIC-ICWC colleagues stressed the importance of the modeling tool and the value of collaborating with international organizations, model developers, and regional and national organizations on multiple occasions. They emphasized that the modeling tool can facilitate new ways of collaboration across various stakeholders. The two-year collaboration with SIC ICWC culminated in the official handover of the Chirchik River Basin Pywr model to SIC ICWC, the model owners, during the Nexus Gains wrap-up workshop in November 2024. This milestone is a step forward in advancing sustainable water management in Central Asia and highlights the value of partnerships in building tools to help address regional challenges.
Sherzod Muminov, Deputy Director at SIC-ICWC said that collaboration on the Chirchik River Basin Pywr model was just the beginning of future collaboration. “I thank the IWMI team for your ongoing collaboration and efforts in co-testing the Pywr model on the example of optimizing water allocation in the Chirchik River basin. As tested during the training, its user-friendly interface enables the simulation of complex water systems under various scenarios, including climate change impacts and competing demands from energy, agriculture, industry, and domestic sectors. The model also effectively addresses the region’s transboundary nature of water resources, facilitating improved decision-making for equitable and sustainable water management to the Amu Darya River basin.”
Future steps
The collaboration between IWMI, UoM and SIC-ICWC demonstrated the value of cooperating on trialling new state-of-the-art analytical tools. Pywr models run quickly, which allows evaluating interventions under many future scenarios and enables connecting to Artificial Intelligence-aided design tools. If these capabilities are taken onboard by local actors, they will bode well for future water management in Central Asia. Partnership between regional and international practitioners helps to co-produce tools that are sustainable and fit for purpose. Expanding the application of Pywr to other, larger basins in Central Asia, as suggested by Dr. Muminov, could further support the region’s ability to address shared water management challenges.
This work was carried out under the CGIAR NEXUS Gains Initiative, which is grateful for the support of CGIAR Trust Fund contributors: www.cgiar.org/funders
