Integrated Adaptive Water Allocation Scenarios for Wetland Restoration: A Case Study of Lake Marmara Under Climate Change

Wetlands, as critical ecological systems, face increasing threats from anthropogenic pressures and climate change. This study investigates dynamic water allocation strategies for the restoration of Lake Marmara, a nationally important wetland within the Gediz River Basin of Türkiye, which has experienced complete desiccation in recent years. Within the scope of the PRIMA-funded “Mara-Mediterra” project, an integrated modeling approach was employed to evaluate multiple restoration scenarios using the WEAP (Water Evaluation and Planning) platform. Scenarios varied based on the initial storage capacity of Gördes Dam, irrigation demands, environmental flow priorities, and a potential water diversion investment from the Tabaklı reach. Results indicate that under current conditions, Lake Marmara’s ecological water needs can be sustained without the Tabaklı investment. However, under 2050 climate projections, scenarios lacking the Tabaklı investment or deprioritizing ecological needs consistently failed to meet the lake’s minimum water thresholds. Conversely, scenarios combining moderate dam storage levels, environmental prioritization, and Tabaklı inflow succeeded in restoring lake volumes by over 90%. These findings highlight the need for adaptive water planning that aligns with projected hydro-climatic shifts to ensure long-term wetland sustainability.