PRESERVING URMIA LAKE IN A CHANGING WORLD: Reconciling anthropogenic and climate drivers by hydrological modelling and policy assessment SOMAYEH SHADKAM Thesis committee Promotor Prof. Dr P. Kabat Professor of Earth System Science, Wageningen University & Research Director General of the International Institute for Applied Systems Analysis (IIASA) Laxenburg, Austria Co-promotors Prof. Dr F. Ludwig Personal chair at the Water Systems and Global Change Group Wageningen University & Research Dr P.R. van Oel Assistant professor, Water Resources Management Group Wageningen University & Research Other members Prof. Dr B.J.M. Arts, Wageningen University & Research Prof. E. van Beek, University of Twente, Enschede Prof. Dr C.M.S. de Fraiture, Unesco-IHE, Delft Prof. Dr S. Morid, Tarbiat Modares University, Tehran This research was conducted under auspices of the SENSE research school PRESERVING URMIA LAKE IN A CHANGING WORLD: Reconciling anthropogenic and climate drivers by hydrological modelling and policy assessment SOMAYEH SHADKAM Thesis submitted in fulfilment of the requirements for the degree of doctor at Wageningen University by the authority of the Rector Magnificus, Prof. Dr A.P.J. Mol, in the presence of the Thesis Committee appointed by the Academic Board to be defended in public on Monday 29 May 2017 at 4 p.m. in the Aula. Somayeh Shadkam Preserving Urmia Lake in a Changing World: Reconciling anthropogenic and climate drivers by hydrological modelling and policy assessment 140 pages. PhD thesis, Wageningen University, Wageningen, the Netherlands (2017) With references, with summaries in English, Dutch and Persian ISBN 978-94-6343-186-6 DOI: 10.18174/413386 Abstract Urmia Lake, in north-western Iran, is an important internationally recognized natural area designated as a RAMSAR site and UNESCO Biosphere Reserve. Over the last 20 years, the surface area of Urmia Lake has declined by 80%. As a result, the salinity of the lake has sharply increased which is disturbing the ecosystems, local agriculture and livelihoods, regional health, as well as tourism, which could amplify economic, political and ethnic tensions in this already volatile region. In response to that, Iranian government established the ten-year “Urmia Lake Restoration Program (ULRP)” proposing six approaches in terms of controlling, protecting, surveying, studying and supplying water from other sources. This study first assessed the main reasons for the decreased inflow using the Variable Infiltration Capacity (VIC) hydrological model, including reservoirs and irrigation modules. The results showed that climate change was the main contributor to this inflow reduction. However, water resources development, particularly water use for irrigation, has played a substantial role as well. In the second step assessed Urmia lake inflow under future climate change and irrigation scenarios. Then, the (VIC) model was forced with bias-corrected climate model outputs for both the lowest (RCP2.6) and highest (RCP8.5) greenhouse-gas concentration scenarios to estimate future water availability. The results showed that the water resources plans are not robust to changes in climate. In other words, if future climate change is limited due to rapid mitigation measures (RCP2.6) the new strategy of reduction of irrigation water use can contribute to preserve Urmia Lake. The next step of this study assessed the quantitative impacts of ULRP by introducing a constructive framework. The framework depicts real water saving by distinguishing between water withdrawals, depletion, and demand in the context of uncertainties in future demand and supply. The results showed that although the ULRP helps to increase inflow by up to 57% it is unlikely to fully reach its target for three main reasons. The first reason is decreasing return flows due to increasing irrigation efficiency. The second reason is increased depletion which is due to neglecting the fact that agricultural water demand is currently higher than available water for agriculture. The third reason is ignoring the potential impact of climate change. However, there still can be some additional none-quantifiable barriers and challenges that may cause the failure of the restoration plan. Therefore, in the last step, this study used two types of qualitative data to explore these aspects: first, the opinions from 40 experts and the in-situ observation of some of the ULRP implementation practices. The results indicate a number of challenges for the ULRP implementation including the water use regulations and the agricultural measures. In addition, (water) demand-side measures such as crop pattern changes were more supported, as opposed to supply-side measures. This thesis showed that the sustainable approach to preserve Urmia Lake should incorporate both demand management (considering socioeconomic complexity) and flexible supply management strategies (to deal with uncertainties in climate variability and change) in a participatory approach. To be prepared for the future, also scenarios with reduced inflow into Urmia Lake, either due to climate change or water resources development, need to be considered to deal with considerable amounts of variability in the current system and with future changes in climate and socioeconomic conditions. CONTENT CHAPTER 1: Introduction .............................................................................................................................. 4 1.1. Impact of climate and water resources developments on natural environments in water stressed areas ........................................................................................................................................ 6 1.2. Strategies to save water for natural environments in water stressed area ................................ 7 1.3. Urmia Lake .............................................................................................................................. 8 1.4. Research objectives and questions ........................................................................................ 11 1.5. Methods ................................................................................................................................. 11 1.6. Thesis outline ........................................................................................................................ 14 CHAPTER 2: Impacts of climate change and water resources development on the declining inflow into Iran's Urmia Lake ................................................................................................................... 16 Introduction ........................................................................................................................... 18 Study area .............................................................................................................................. 19 Method................................................................................................................................... 21 Results ................................................................................................................................... 24 Discussion ............................................................................................................................. 30 Conclusions ........................................................................................................................... 33 CHAPTER 3: Preserving the World Second Largest Hypersaline Lake under Future Irrigation and Climate Change ................................................................................................................. 34 Introduction ........................................................................................................................... 36 Study area .............................................................................................................................. 37 Materials and methods ........................................................................................................... 38 Results ................................................................................................................................... 41 Discussion ............................................................................................................................. 45 Conclusions ............................................................................................................................ 48 CHAPTER 4: Water-saving interventions assessment framework: an application for the Urmia Lake Restoration Program ........................................................................................................... 50 4.1. Introduction ........................................................................................................................... 52 4.2. Method................................................................................................................................... 53 4.3. Urmia Lake Restoration Program (ULRP) ............................................................................ 56 4.4. Results ................................................................................................................................... 61 4.5. Discussion ............................................................................................................................. 67 4.6. Conclusion ............................................................................................................................