The feasibility of implementing a low-emission zone in central Makkah: environmental indicators and urban quality implications

Abstract

The Central Area of Makkah faces severe seasonal environmental pressures from heavy vehicular traffic, particularly during Hajj. Using the DPSIR framework, this study conducts a spatial and environmental diagnosis of this high-density urban core. To assess the environmental conditions, spatial sampling and field measurements were conducted at 32 strategic locations, using a calibrated Extech VPC300 Video Particle Counter for PM2.5 and PM10, along with portable multi-parameter detectors for CO and CO2. Field measurements captured two seasonal operational extremes: Phase 1 (baseline peak congestion, 20 Dhu Al-Qi’dah 1446AH) and Phase 2 (strict traffic cordon restrictions, serving as a real-world LEZ proxy, 2 Dhu al-Hijjah 1446AH). Paired-samples t-test validation indicates that during peak congestion, localised CO2 reached 1,750 ppm and noise peaked at 95 dB, while localised PM2.5 and PM10 particle counts demonstrated elevated concentrations. Methodological baseline calculations reveal that the localised prayer shuttle fleet generates a carbon footprint four times larger (57,888 tons of CO2) than the inbound regional fleet, condition compounded by the dense ‘street canyon’ morphology. Conversely, spatial analysis identifies 2.5 million m2 of vacant land. As a targeted ‘Response’, this paper introduces the Makkah Low Emission Zone (M-LEZ) framework. Distinct from conventional urban LEZs, the M-LEZ introduces a dynamically phased seasonal framework that utilises underused peripheral land for green infrastructure and transit hubs. It aims to balance mass transit logistics with microclimate sustainability and promotes public health for pedestrians.