You are here: Home Knowledge Base Environment Reducing the Water and Waste Footprints of Megacities Solutions Treat waste and sewage as a resource, and increase recycling and reuse. Take account of engineering, economic and social viewpoints to implement a range of potential options to make better ...
Symposium 2011

Solution for Reducing the Water and Waste Footprints of Megacities

The Challenge

The United Nations estimates that the number of megacities with a population of more than 10 million will triple from 20 in 2003 to 61 in 2015. It is estimated that more than nine tenths of urban grow ...

The United Nations estimates that the number of megacities with a population of more than 10 million will triple from 20 in 2003 to 61 in 2015. It is estimated that more than nine tenths of urban growth will occur in developing nations, with four fifths of urban growth occurring in Asia and Africa.

Treat waste and sewage as a resource, and increase recycling and reuse. Take account of engineering, economic and social viewpoints to implement a range of potential options to make better use of water and solid waste.

Waste and sewage need to be understood as a valuable resource rather than something unwanted. Increased recycling and reuse will reduce the footprints of megacities. Growing cities mean that there needs to be a range of potential options to make better use of water and solid wastes. The challenge needs to be looked at from biophysical, engineering and economic and social viewpoints. City planners and policy-makers need to realize the potential to do this and put their support behind innovation in this sector, including the development of effective business models.

For emerging megacities in developing countries, Western models of waste disposal and sewage treatment are usually too expensive and require knowledge of the technology. Innovative low-cost engineering solutions are required, for example, providing limited primary treatment for the sewage and then using the waste water and separated solids in agriculture or to produce biogas and fertilizer.

    Implemen- tations

    Implementation
    Symposium 2011

    Building Walls with Waste

    Polity, Academia, Business, Civil Society

    Related Solutions

    Solution
    Symposium 2011

    Water should be charged at its actual cost, reflecting both its nature as a scarce resource and the cost for infrastructure. Avoid subsidies, which encourage overuse.

    Water should be charged at its actual cost, reflecting both its nature as a scarce resource and the cost for infrastructure. Avoid subsidies, which encourage overuse.

    Water should be charged at its actual cost, reflecting both its nature as a scarce resource and the cost for infrastructure. Avoid subsidies, which encourage overuse.

    Polity, Business
    Solution
    Symposium 2011

    Involve all stakeholders in tailor-make solutions to local circumstances to finance infrastructure, to improve institutional effectiveness or to include informal urban settlements.

    Involve all stakeholders in tailor-make solutions to local circumstances to finance infrastructure, to improve institutional effectiveness or to include informal urban settlements.

    Involve all stakeholders in tailor-make solutions to local circumstances to finance infrastructure, to improve institutional effectiveness or to include informal urban settlements.

    Polity, Business
    Solution
    Symposium 2011

    Policy-makers need to implement water markets and existing economic and technological solutions for water and waste problems.

    Policy-makers need to implement water markets and existing economic and technological solutions for water and waste problems.

    Policy-makers need to implement water markets and existing economic and technological solutions for water and waste problems.

    Polity
    Solution
    Symposium 2011

    Raise public awareness about waste and water footprints.

    Raise public awareness about waste and water footprints.

    Raise public awareness about waste and water footprints.

    Polity, Academia, Business, Civil Society