Water has become a challenge of global dimensions, especially in the fast-growing urban areas, which is an under-recognized issue for many citizens, a recent study published in Science by a research team from Switzerland and the Netherlands pointed out.
Attention has usually been paid to water-related issues such as drought, flood, agriculture, food, and the quality of water received. Little concern has been given to cities’ ability to handle the urban water cycle adequately.
With rapidly aging infrastructure, population growth, and increasing urbanization, current urban water management strategies are questionable, especially in the fast-growing urban areas in Asia and Africa.
The existing urban water management system is mainly built on a well-established socio-technical system that has solved most of the water and hygiene-related problems afflicting cities, especially in the more affluent part of the world. It relies on investment-intensive, usually underground, pipe networks that provide single-quality drinking water and evacuate stormwater and wastewater.
In many urban areas, reservoirs, and long-distance water conveyance systems compensate for inadequate local water resources. In addition, water and wastewater treatment plants provide an interface to the aquatic environment, treating raw water for drinking water purposes and wastewater for water pollution control.
The core centralized services in the existing urban water management system include providing safe drinking water, urban hygiene, and protection against flooding, complemented by water pollution control. These approaches have worked well at a good quality in many cities and metropolitans.
Apart from providing safe drinking water and handling wastewater for public health, an additional important infrastructure is the stormwater drainage system. Without adequate drainage infrastructure, unwanted urban flooding events will occur. Thus, protection against flooding is one of the top priorities for urban water sustainability.
According to the study, conventional urban water management systems are not the best solution for rapidly growing cities because of their strong dependence on large quantities of water, high investment costs, need for stable institutions, long planning horizons, and inefficient resource use. Of these disadvantages, inefficient resource use is a global issue. Currently, the conventional system is incurring increasing economic, social, and environmental costs due to aging built infrastructures, increasing urbanization, emerging contaminants, and competitive water uses.
Currently, the overall treatment of the collected wastewater remains highly insufficient in many cities, especially in Africa and Asia, because of the scarcity of sewers and treatment plants. This backlog is compounded by the current unprecedented global population growth rate. Small and medium-sized towns will bear the brunt of this future urbanization growth, notably providing access to safe drinking water and sewers. High urban growth rates lead to high planning uncertainty.
As the currently dominant conventional approach to water management is unlikely to meet the increasing challenges of a globalizing world, the authors noted that a shift toward “new paradigms” is required. These paradigms included integrated water resources management, adaptive management, and ecosystem-based approaches. A shared feature of these reform agendas is that they orient water management toward providing sustainable water services rather than merely delivering quantities of water.
The authors further pointed out that it is not enough to hope for technological breakthroughs or to believe in the wisdom of more inclusive governance arrangements alone. Rather, the joint development of new institutional conditions and technological designs is needed. They have documented several promising alternative technological and institutional approaches, such as stormwater drainage, increasing water productivity, source separation of waste, and on-site treatment of wastewater.
Currently, rapid urbanization in areas with water scarcity and/or missing or aging urban water infrastructure is an immense challenge and a formidable chance for developing next-generation technologies and management structures. The authors said there is an urgent need to develop more cost-effective and resource-efficient systems that deliver the desired water services for areas with fast-growing urbanization.
Relevant scholars at the University of Hong Kong further pointed out that raising the public’s awareness and appreciation of long-term water sustainability for urban residents would also be important. They have recently launched a 3-year JC-WISE (Jockey Club Water Initiative on Sustainability and Engagement) project, funded by The Hong Kong Jockey Club Charities Trust, aiming at elevating the level of public awareness of the importance of water conservation and sustainability by enhancing the understanding of the multiple values of water through re-connecting the public with local rivers and recognizing the impacts of consumption habits on local and distant freshwater resources.
Scholars at the University of Hong Kong said that, informed by this new understanding, one can then take personal and collective actions to reduce the size of one’s water footprint and, thus, the extent of its impacts to contribute to water sustainability goals. Hong Kong’s experience may affect water management in other cities or urban areas.
