Rainwater Harvesting as a Sustainable Water Security Strategy for Vision 2030 Urban Development Projects

Urban development projects under Vision 2030 are transforming cities through giga-projects, tourist attractions, industrial areas, and urban infrastructure upgrades in one of the most climate water-stressed regions where desalination, aquifers' safeguarding, and treated wastewater use are crucial yet not sufficient alone. This literature review investigates rainwater harvesting (RWH) as a water security strategy for urban developments under the Vision 2030 program in Saudi Arabia. Based on a review of literature from 2020 to 2025, government publications, and case studies in the arid region, the paper aims to analyze the potential contribution of RWH technologies including rooftop systems, public-space cisterns, SUDS, wadis, aquifer recharge facilities, and intelligent monitoring to potable water savings, prevention of sudden floods, and aquifers' safeguarding. A structured narrative approach will be applied in this study focusing on four key questions about relevance of RWH to urbanization in Saudi Arabia, applicable technologies to arid cities, assessment criteria, and governance model for implementation of these solutions. The findings suggest that RWH should not be considered a minor green element for cities. The highest contribution of this technique can be expected from integrated portfolios combining distributed RWH, district detention, purification, recharge of the underground aquifer, and reuse of harvested water for irrigation, air conditioning, street sweeping, and construction needs. This paper develops an urban Vision 2030 RWH framework including site location, engineering design, water quality management, cost-effectiveness analysis, and community engagement.