Today water stress is a major concern in many urban areas. The core aspect of urbanisation is the rapid urban population growth together with inadequate planning, pollution, poverty, competing demands on the resource, all contribute to water stress: and consequently the urban water consumption is likely to double by 2025. Climate change is expected to cause significant changes as well in precipitation patterns which will affect the availability of water and induce water related disasters.
The world urban population is expected to increase by 72 % by 2050, from 3.6 billion in 2011 to 6.3 billion in 2050. African and Asian urban population is expected to be around 57.7 and 64.4% at urbanisation rate of 1% and 0.9% respectively. In developing countries, average sanitation coverage (56%) is far less than water coverage (85%). For example in Africa, even in urban area coverage for sanitation is 46% and water is 84% and the coverage is even significantly lower in the rural areas.
Current models of urban planning and water management have already failed or likely to fail from the perspective of cost effectiveness, technical performance, social equity, and environmental sustainability. A paradigm shift is required at the system-wide level. Integrated Urban Water Management (IUWM) provides a framework for interventions over the entire water cycle and a reconsideration of the way water is used (and reused). And IUWM balances competing demands among water users: agriculture, industry, household, and ecosystems. More governments recognise the importance of taking such an approach to address the challenges of cities. There is growing consensuses around the principles of Integrated Urban Water Management (IUWM) which include the three main inter connected dimensions:
- Governance: It is a critical aspect for supporting IUWM. Without government policy and framework support and comprehensive stakeholder participation, optimum management of water resources cannot be achieved.
- Service: This component includes closed loop systems for water supply and sanitation (making whole water cycle as one), stormwater management, good Operation & Maintenance and at the same time maintaining the water quality as required for use. Decentralised wastewater treatment systems and innovative and affordable technologies are recommended.
- Resource: It is of utmost importance to make use of all available resources; conventional or unconventional in the form of wastewater, rainwater, surfacewater, greywater, blackwater etc. Wastewater is not wasted water! Simultaneously, demand side management should be utilised to lessen the stress on water resources.
Cities: a wealth of opportunities. Urbanisation also brings with it opportunities for more efficient water management as well as for the provision of drinking water supply and sanitation services to many people. Cities are generators of wealth and employment, incubators of innovation and creativity, and provide the best opportunities to improve livelihoods.