Irrigation Water Demand Management-Based Innovative Strategy: Model Application on the Green Riyadh Initiative, Saudi Arabia

Water demand is expected to dramatically increase due to the spread of green and landscape project developments. The main objective of this study is to enhance water demand management in Riyadh, Saudi Arabia, based on an innovative strategy utilizing remote sensing techniques. Furthermore, this study focuses on the Green Riyadh initiative, which emphasizes the need for sustainable water use in urban green areas amidst growing water scarcity. The majority of urban water supplies for irrigation are utilized to maintain vegetation health, aesthetic appearance, and municipal amenities. By employing advanced remote sensing (RS) techniques through Landsat 8 satellite imagery alongside ground-verification methodologies, the research develops a new approach called the Plant Coefficient Method (PCM) to estimate plant evapotranspiration (ETpl) rates for various landscape plants. The study quantifies water demands and evaluates the relationship between plant coefficient values, reference ET rates, and vegetation indices, revealing distinct patterns in spatial and temporal water usage, identifying effective species selections, and providing essential insights for enhancing water conservation strategies in arid environments. Moreover, the study exposes an average annual precipitation of just 73 mm in Riyadh and finds that with good management based on PCM, average daily projected ETpl rates may be as low as 2.6 mm/day, greatly decreasing water needs by around 70% to 50% when compared to higher categorization situations. The findings underscore the importance of integrating accurate ET estimation methods in irrigation planning to support sustainable landscape management and minimize the ecological impact of urban development in drought-prone regions.