New aspects of urban drainage and pollution reduction towards sustainability

A very basic problem of open material flows resulting in accumulation of pollution is not adequately addressed in present societies. Developed countries with expensive water-related infrastructure still contribute to local and global pollution. Developing countries to a great extent lack water treatment facilities and environmentally sound water management. Large scale end-of-pipe wastewater treatment is one of the spectacular examples of technologies that must change in order to provide a sustainable solution. In order to start the way towards a solution of increasing worldwide pollution problems, a new holistic approach to resource management must be applied. The final goal of such an approach is to close the cycles of residuals that damage the environment, and recover resources lost in residuals emitted from all human activities. Water management should be integrated with management of other activities such as waste handling, industrial production, transportation, energy production, etc. The most important action is to apply pollution prevention strategy, i.e. to prevent pollution formation at the source during all human activities. Different kinds of effluents should be separated instead of mixed together. Recycling of water, nutrients and solid residuals should be arranged on a lowest possible level of human settlements. Technologies exist that can solve the problem of pollution from wastewater on a very basic level of a single house or residential area. Stormwater flows with different origin can be separated and disposed locally or re-used in a single house. Industries should modify technologies so that, eventually, wastewater is not produced at all, instead all fluid, solid and gaseous residuals are recovered and recycled. Tools for implementation of such solutions are: legislation and administrative actions coupled with education programmes on all societal levels, increasing public awareness, competition rules of the market economy based on long-term profits. The goal is sustainability of the society by resource recovery and re-use. Demonstration projects, in which the rules of preventive approach and novel technology is applied may constitute a practical way of implementing such an approach.