Petra, one of the Seven Wonders of the World, which has welcomed 1,135,300 visitors in 2019, is prone to witness more hydrological hazards, including flash floods, landslides, and earthquakes, due to climate change, urban expansion at the site’s neighboring areas, and its geological location near the Jordan rift valley.
In light of that, the Inter-Islamic Network on Water Resources Development and Management (INWRDAM), Disaster Prevention Research Institute (DPRI) of Kyoto University, Japan, and Petra Development & Tourism Region Authority (PDTRA) joined forces, and organized the 6th International Symposium on Flash Floods in Wadi systems (6th ISFF) between 26-30 September 2021 in Amman, allowing researchers and practitioners to exchange experiences and share knowledge on integrated management of Wadi Flash Floods in arid and semi-arid regions. Moreover, the 4th day of the 6th ISFF included a guided tour to Petra.
At Petra, situated between the Red Sea and the Dead Sea, researchers and practitioners were briefed on the ingenious water management system which dates back to the Nabataeans, the ancient inhabitants of the site. This system mitigates the dangerous hydrological hazards’ effects of flash floods, and stores water for use in the dry season.
Over the years, these Nabataean water systems deteriorated. In addition, climate change and urban sprawl added other layers of complexity to the situation.
In 1963, 21 French tourists and two tour guides drowned in the Siq during a disastrous rainstorm. Consequently, the Jordanian government reconstructed the ancient dam at the entrance to the gorge to control flooding. Additional structures were put in place in the 1990s, to direct floodwaters into the same diversion tunnel that the Nabataeans built some 2,000 years earlier.
Similarly, on the 9th of November 2018, a significant flooding event impacted the site, trapped visitors, and forced 3,000 tourists to evacuate to safe places within 1 hour before the flood peak, raising even more awareness of the urgency to mitigate this disaster.
Accordingly, PDTRA and UNESCO joined efforts to protect the site from flooding hazards since September 2018. Commencing in July 2019, the Heritage Emergency Fund (HEF) at the World Heritage Centre funded initiative to propose an integrated hydrologic-hydraulic model grounded on extensive inputs for the Wadi Musa. This study was created to define the flood plain and identify high-risk locations within the Petra Archaeological Park.
As a final output of the study, some structural and non-structural solutions have been proposed by considering their compatibility with Petra's specific characteristics and values as a UNESCO World Heritage Site, thus supporting a sustainable approach to its comprehensive safeguarding.
These solutions proposed under the UNESCO flash flood Risk reduction at the World Heritage Site of Petra included: "Attenuation structures (dams), Channel upgrade, Culvert upgrade, Watershed management measures (terracing), Flow diversion works (diversions tunnel), Rainfall warning systems and the Introduction of warning signs at critical locations, as UNESCO representative Giorgia Cisaro explained.
In turn, Dr. Hussein Alhasanat, Director for Disasters Management Directorate at PDTRA pointed out the measures adopted to reduce the severity and frequency of flood and flash flood risks. These measures included: "Prevention and mitigation, rehabilitation, flood forecasting and warning, awareness, capacity building, preparedness, urban planning, land use planning risk identification, and assessment, developing response emergency plan and recovery and reconstruction plans."
Within this framework, 10 Nabatean dams were rehabilitated in Al-Harimiya. Wadi Al-Harimiya is a small catchment that flows into the Treasury Plaza and is responsible for much of the flooding there. The project funded by GIZ aims to mitigate the flow of water and protect the archaeological site and its visitors.
Still, that is not enough to safeguard the site itself and the visitors. The primary debate is whether to build a large dam that has the advantage of reducing the peak flow or a large number of small check-dams, which had the benefit of delaying peak time.
According to a paper entitled the "Hydrological assessment and management implications for the ancient Nabataean flood control system in Petra, Jordan", published in the Journal of Hydrology (Volume 601, October 2021, 126583), constructing and calibrating hydrological models using HEC-HMS and HEC-RAS software have shown that terraces are effective at delaying the flood peak time (up to 25-minute delay for an 18 dam setup) and at reducing the actual amount of water arriving downstream (13.5% volume reduction). Similar results can be observed for lower frequency flood analysis, in which the models also show the effectiveness of these interventions. For example, modeling a large dam, rather than the smaller terraces and check dams, shows that such an intervention would reduce 30.5% in peak flow but a delay of merely 14 minutes.
However, PDTRA does not want to favor any of the above options. Dr. Hussein Alhasanat explains: "Only an independent study by an independent entity let it be an excellence center or university, would encourage donors to fund the above-mentioned potential solutions to safeguard Petra."
In this regard, Dr. Sameh Ahmed Kantoush, Associate Professor at Kyoto University in Japan, expressed the willingness of the Japanese universities to lend a hand to PDTRA in terms of transferring technology, establishing excellence centers for creating a credible regional database , and putting in place a more effective warning system that includes: satellite remote sensing, weather radar, ground rain gauge, water level gauge, flash flood, impact gauge, 6 ITV camera system, early warning data, analyzing method, and early warning trans-mission system with Siren, ICT (area mail with a mobile phone, etc.)
What Dr. Kantoush proposed at the technical level would be complemented if "Strengthening the resilience and adaptive capacity of vulnerable World Heritage sites (WHS) in Petra goes hand in hand with efforts to raise awareness and integrate measures into the country strategies and planning", Dr. Marwan Alraggad, the executive director of INWRDAM said.
Therefore, "Solutions are possible if we combine the political will with technical means and put in place additional monitoring stations to limit the increase in climate change impacts, through implementing an urgent collective action plan not limited to Petra but includes the MENA region".
Tourism
At the Tourism level, PDTRA and the Japanese International Cooperation Agency (JICA) launched Petra region's comprehensive tourism plan in October 2020. The objective is to make the Petra tourism sector more resilient and self-reliant, as JICA Representative Marie Saito highlighted.
The cooperation between JICA and the PDTRA dates back to 2014 and was materialized by two important projects, namely a grant to establish the Petra Museum and the Project for Community-Based Regional Tourism Development in the Petra Region.
The two projects aim to achieve a more sustainable tourism environment, as the museum displays and narrates the history of the Petra Archaeological Reserve. In addition, the technical cooperation project works to promote tourism that focuses on community participation.
In sum, PDTRA is looking forward to benefiting from Japanese expertise, especially in reducing flood risks, vulnerabilities to natural hazards, especially flash floods, and enhancing building resilience. To reach there, INWRDAM and Kyoto University aspire to establish a network of meteorological monitoring, and foster young researchers, paving the way to an International Collaborative Network and technology transfer, not only to safeguard Petra, which was forgotten until a Swiss explorer by the name of Johann Ludwig Burckhardt rediscovered it in 1822 but the whole MENA region and countries of The Organisation of Islamic Cooperation.