Urban Nexus // Innovative Waste Water Management Workshop on Vacuum Sewer Systems in the United Arab Emirates
By Ruth Erlbeck, Ralph Trosse & Rashane Sala-Ngarm (The Urban Nexus Project). Most cities in Asia and the Middle East face similar issues regarding the collection of wastewater from households and other units. A workshop held in Dubai and Abu Dhabi, United Arab Emirates (UAE), from 6 to 7 November 2018, addressed these issues by introducing a specific vacuum waste water collection technology. This technology provides cities with an alternative solution to the conventional gravity system. The workshop was held in the framework of GIZ “Integrated Resource Management in Asian Cities: The Urban Nexus”.
Innovative Wastewater Management Workshop
Most cities in Asia and the Middle East face similar issues regarding the collection of wastewater from households and other units. A workshop in the framework of GIZ “Integrated Resource Management in Asian Cities: The Urban Nexus”, addressed these issues by introducing a specific vacuum waste water collection technology. It was held in Dubai and Abu Dhabi, United Arab Emirates (UAE), from 6 to 7 November 2018.
25 participants from four countries (China, Indonesia, Thailand, and Vietnam) attended the workshop and site visits. Attendees ranged from high-level representation from the national level to the city level.
Main focus of the workshop has been the technology and suitability of vacuum wastewater collection systems for Asia and the Middle East. Wastewater vacuum technology allows cities to build or expand wastewater collection networks to urban areas which are difficult to access (such as small roads, densely populated areas, flat land with no slope, beach areas and areas along river banks). This in turn would enable cities to contribute to Sustainable Development Goals (SDG) 6 (Clean Water and Sanitation), 11 (Sustainable Cities and Communities) and 13 (Climate Action). It could potentially contribute to SDG 7 (Affordable and Clean Energy) if the collected waste water is used as resource for energy production.
Vacuum Sewer Systems
Technological advancements and increased awareness on the untapped potential of wastewater as a source of water, energy and nutrients has led to the emerging of new concepts in this area. While in the past most sewer systems were designed to capture municipal wastewater as well as storm water, modern concepts involve increased material flow separation.
A vacuum sewer system works in a similar way as water distribution systems, only with a reversed flow. While the water distribution system uses positive pressure to ‘push’ the water from the treatment plant to the point of consumption, vacuum sewer systems use negative pressure to ‘draw’ the wastewater from the point of generation to the wastewater treatment plant.
A special feature of the vacuum system is the fact that it is a closed system. Exfiltration into the environment is very unlikely as the vacuum system is under lower pressure than the environment. Because of this, vacuum lines can be placed in the same trenches as the drinking water mains. It also makes vacuum systems suitable for water protection areas or areas with high-groundwater tables.
These features facilitate installation and servicing of the network for every stakeholder, especially when the water service provider is the same entity as the wastewater service provider. Another reason why vacuum sewers have gained increased popularity is it's potential cost advantage over conventional gravity sewer.
Visit of Palm Jumeirah Waste Water Collection In Dubai
All participants of the workshop had the opportunity to see an active vacuum wastewater collection by visiting the Palm Jumeirah housing complex in Dubai. They also observed the waste water treatment plant for the 23,000 inhabitants in the Palm area.
Palm Jumeirah Waste Water Collection in Dubai is the biggest application of vacuum sewer wastewater collection and treatment worldwide. Towards the end of November of every year, Yas Island in Abu Dhabi hosts a five days event of Formula 1 car racing. During those five days about 60,000 visitors come to the racing tracks every day. The wastewater collection system must therefore be able to handle a seasonal and high waste water load.
This visit was exceptionally interesting for other participating cities with seasonal tourism such as Chiangmai (Thailand) and Danang (Vietnam), who could see the possibility of applying the vacuum wastewater collection system in their cities.
Generally the participants gave positive feedback on all parts of the workshop and site visits and said that the new perspectives and knowledge gained are of excellent value to their waste water management and urban development work. Participants expressed their intention of applying the vacuum waste water collection technology in suitable areas of respective cities.