A plan to improve Abu Dhabi’s waste management and water treatment

With a growing economy and population, the emirate of Abu Dhabi continues to consume more and, as a result, produce a substantial amount of waste. In recent years the emirate has succeeded in reducing the amount of solid waste produced, from 9.6m tonnes in 2009 to 8.39m tonnes in 2015, according to official statistics reported by Tadweer. However, the amount is still high, and finding ways to manage waste effectively will be an ongoing challenge. At the same time, ever-greater quantities of desalinated water are being consumed; yet of the 850,000 cu metres of wastewater generated daily only around 60% is reused. The rest is discharged back into the sea. Addressing these issues of waste management are, respectively, the Abu Dhabi Centre of Waste Management (known as Tadweer, and responsible for solid waste), and the Abu Dhabi Sewerage Services Company (ADSSC). Both have big plans to make better use of the waste produced in the emirate.

An Integrated System

Recycling construction and demolition (C&D) waste can preserve raw materials, energy and water in addition to reducing the production of greenhouse emissions. Eisa Saif Al Qubaisi, general manager of Tadweer, told OBG the master plan project (see overview) “aims to build a roadmap to turn Abu Dhabi from the traditional waste management model based on production, consumption and damage to the evolving model based on a sustainable, circular economy.” He added that Abu Dhabi stood to reap “enormous environmental, social and economic benefits” from the master plan, which was described as the first of its kind in the GCC.

A Targeted Approach

While no additional announcements have yet been made regarding funding for the project, the plan is expected to focus in particular on dealing with the huge quantities of waste produced through C&D works in Abu Dhabi.

At the launch of the plan Tadweer explained that the new model would need to be “very targeted”. “It won’t be ‘one size fits all’. “We’re looking at recycling, recovery, public awareness, information and education. We look at what facilities we need, what size and where.” The plan aims to integrate new facilities with existing ones, while landfills where waste is currently dumped will be restructured for more energy-efficient and environmentally sound methods. In particular, Tadweer described a need for transfer stations, regulation and enforcement in recycling, increased public awareness and better-engineered dumpsites.

As a part of the strategy to transform waste into resources that can be utilised environmentally and economically, in February 2016 Tadweer launched an initiative for converting waste cooking oil into clean energy in collaboration with the Masdar Institute of Science and Technology. The pilot phase of the project commenced at Al Raha Gardens community in Abu Dhabi on February 9, 2016. The collected waste oil will be processed by Masdar Institute’s waste-to-energy laboratory into biodiesel, which will then be used to power the waste collection fleet.

Much-Needed Step

Given the emirate’s limited freshwater supply, reuse and recycling projects are further developed than those addressing solid waste. According to the ADSSC, Abu Dhabi is experiencing a 9-10% growth in wastewater flows every year, with a doubling roughly every decade. To meet this growing demand ADSSC has invested Dh5.2bn ($1.42bn) in the Strategic Tunnel Enhancement Programme (STEP), which will begin initial operations towards the end of 2016. The programme involved the creation of one of the world’s largest gravity-driven sewerage networks, featuring a main tunnel running 42 km. Providing a long-term solution to Abu Dhabi’s needs beyond 2030, the system will have an ultimate capacity to accommodate an average flow of 1.7m cu metres per day by 2030. The elimination of 34 existing pumping stations will additionally reduce the potential for sewer system overflows, resulting in improved health and environmental benefits and providing new land for redevelopment. “STEP provides much-needed relief to existing sewerage infrastructure,” Alan Thomson, managing director of ADSSC, told OBG. “It has been built with huge population growth in mind, and is designed to handle a tripling of usage by 2030, with a design life of 80 years. Crucially, it will have huge scope for additional capacity expansion, which is vital when constructing these long-term utilities infrastructure projects.” Abu Dhabi City’s growth will mean further improvements in ADSSC’s network will be required. Thomson told OBG, “Even with increased environmental awareness, it is expected that water usage will continue to expand heavily, primarily due to Abu Dhabi’s rising population. This means there will be a further need for rehabilitation and upgrading of the existing system, including over 300 pumping stations, as well as addressing the hydraulic capability of the network’s older sewers.”

The Mechanical and Civil Engineering Contractors Company has been actively involved in the sewer rehabilitation schemes on Abu Dhabi island for the past three years. The company’s chairman, William Haddad, described STEP as a “grand” scheme that will suffice Abu Dhabi island’s requirements for many years to come, while the project’s sheer scale will mean it continues to generate opportunities within the sector. “The redundancy and abandonment of some 34 pumping stations on the island and its environs will create unknown scopes of work,” he told OBG. “Once this work is completed and the sewage treatment plants are handling the inflows, the treated sewage effluent will also demand new irrigation networks to several areas of the mainland.”

Committed To Sustainability

Uniting both Tadweer’s and ADSSC’s approach is an emphasis on sustainability, and a particular commitment to the so-called three Rs: reduce, reuse and recycle – goals in keeping with the framework of the Abu Dhabi Economic Vision 2030 to make the most of the emirate’s resources. As Thomson emphasises, “We consider STEP to be a green project, as it is purely reliant on gravity to transport sewerage and wastewater, without the need for any power generation. Considering its size, this is an enormous achievement, and will save a vast amount of power while greatly limiting any environmental impact in the long run.”

Recycling Water

In the case of wastewater, however, most admit that more could be done with the large volumes of treated water produced by the system. Once commissioning has been completed on the STEP project, ADSSC’s attentions are likely to turn toward recycled water. A master plan is due by the end of 2015 to examine scope for much greater use of this resource, and the regulator hopes that a body would be appointed to manage demand and the marketing of potential products within this field.

Achieving this outcome, however, will likely require structural change within the sector: as it stands, the transmission system for treated water is owned by ADSSC, but the distribution system falls under the ownership of the various municipalities. Approval will be required to change this model, which will be a likely prerequisite for expanding the use of treated water further afield in agricultural districts such as Al Ain.

Peter Werner, director of the National Water Centre at the UAE University in Al Ain, agrees that, while a lot is already being done, better coordination will be key to greater success in the future. “Our target is to introduce integrated water resource management addressed to scarcity,” he told OBG, “but to achieve that we need to bring everyone to the same table.”

In particular, Werner sees a great deal of potential for greater use of treated waste water in agriculture, with one possibility being to adapt sand dune storage schemes that are being used in parts of Europe. In the meantime, however, he considers Al Ain as the best testing ground to push such schemes forward. “Abu Dhabi island is so fast-growing that it’s difficult for infrastructure to keep up,” Werner told OBG. “Al Ain though could serve as a model for what can be possible with treated waste water reuse,” he added.