Safetyplanning for Mecca, Saudi-Arabia

We employ a simulation-optimization approach to coordinate large pedestrian streams in Mecca, safely.

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Our objective was challenging: to plan crowd movements in one of the largest and most difficult to control mega-events on the planet. Set in a desert environment hostile to human life, the Hajj attracts millions of faithful who attempt to perform the religious rituals once in their lifetime. We began by digitizing the local pedestrian infrastructure such as roads, walkways, stairs, escalators, tunnels, camps, street blocks, and sanitary facilities. Based on this digital infrastructure we developed a pre -event simulation of how the crowd flows through the infrastructure and finally designed a mathematical planning model and algorithm to determine safe pilgrim group departure times and routes for the stoning-of-the-devil ritual (Rhamy-Al-Jamarat). Year for year, we were guests in Saudi-Arabia and gained a deeper understanding of the Hajj organizational structure. With growing experience, we refined our model-based planning and improved our understanding of how to structure and process the massive amount of input-data. We contributed to the Hajj planning process by providing a solid planning method aimed at optimizing safety through spatio-temporal coordination of pilgrim flows.

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Key Challenges

  • Large scale joint optimization project for multiple Saudi-Arabian gorvernmental stakeholders
    • Ministry of Hajj
    • Ministry of Municipal and Rural Affairs
    • Pilgrim Organizations
    • Security Forces
  • A highly challenging, dynamic planning environment
  • Between 2 and 4 million pilgrims per Hajj event
  • Complex infrastructure and multi-mode transportation at the holy sites
  • Massive danger of crowd disasters during peak time periods of the ritual
  • Development of a robust coordination approach to avoid congestion at the ritual sites
  • Integration of optimization approach into Hajj planning software infrastructure and operations

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  • We planned timetables and routes for more than 31 million pilgrims during the projects lifespan
  • In contrast to past years, catastrophic crowd accidents were avoided
  • We held numerous training workshops in Saudi-Arabia
  • We provided consultation services for a number of related logistics optimization questions
    • Infrastructure evaluation using simulation techniques
    • RFID based compliance monitoring
    • Time critical mass ticket distribution
    • Smartphone based pilgrim group dispatching operations
    • Support of high-capacity metro system operations at the holy sites
    • Camp and tent zone optimization for about 400'000 pilgrims

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