Al Zohour Triangle

In response to the significant risk of flash floods in Amman, in 2019 UN-Habitat Jordan implemented the project “Strengthening the Social Stability and Resilience of Vulnerable Jordanian Communities and Syrian Refugees in Amman against Flash Floods”. The expected outcomes included improved protection of selected sites, reduced vulnerabilities of refugees and local communities, and enhanced capacities within government and communities in managing flash floods in the city¹.

One of the research components of the project consisted of the “Flood Risk Assessment and Flood Hazard Mapping” study of Downtown Amman, which identified flood hotspots within the city, and propose short, medium, and long-term solutions to address the issue. The short-term solutions proposed installation of green stormwater infrastructure, the demonstration of which was done in the form of the Al Zohour Green Triangle.

This initiative serves as a pilot and demonstrator of how nature-based solutions and Sustainable Drainage Urban Systems approaches could represent efficient and concrete solutions. It seeks to mimic the way nature handles water; collecting it, purifying it, and then gently reintroducing it into the stormwater system. With potentially 120 other similar sites mapped by the project and where this innovative approach could be massively and easily replicated, the Al-Zohour Green Triangle is a blueprint for effective resilience in the face of floods. 

It was implemented on an area covering 2,300 square meters, located at the intersection of Al Quds street and Bab Al Khalil street within the Al Zohour District of Amman. It follows the principles of a Sustainable Urban Drainage System (SUDS), and works through two primary systems, stormwater bioretention and stormwater detention. For stormwater bioretention, a series of bioretention and bioswale areas are designed that enhance ground permeability through vegetation cover and facilitate the natural water cycle. Stormwater detention is demonstrated through the installation of an underground water storage tank².  

The project has 5 primary components:

• Water inlets: Inlet pipes to direct water from the streets into the bioretention system and the underground water tank.
• Water retention function: Bioretention and bioswales with an approximate capacity of 750 cubic meters, designed to enable ground permeability.
• Water detention function: Underground water tank with a capacity of 2,100 cubic meters
• Water reuse function: Detention tank with a pump to send out water for mobile water tankers or irrigation systems
• Water outlets: Drainage mechanism for excess water, especially during storms
• Landscape: Natural design features to integrate the infrastructure with the city and create an inviting public space

The complete project was implemented UN Habitat Jordan in collaboration with the Greater Amman Municipality, between April 2020 and November 2022, with funds from the Japan Supplementary Budget of the fiscal year 2019. The Al Zohour pilot was launched in 2022, with a total implementation cost of $465,000^3.