Susanne Bieker

Semicentralised supply and treatment systems: integrated infrastructure solutions for fast growing urban areas

Currently, the development of the world population is characterised by two trends: absolute population growth and rapid urbanisation. Especially rapid urbanisation, taking place in Asia, Latin America and Africa, poses major pressure on the affected regions. The development of e.g. Asian countries today is stamped by a combination of urbanisation with high economic growth rates. Conventional centralised infrastructure of supply, treatment and disposal of water is not able to cope with the new challenges arising from these, in history incomparable, high growth rates. Therefore new approaches to infrastructure supply and treatment systems are required - for ecological, sociocultural and economic reasons. The semicentralised approach, focusing on integrated water supply and treatment structures for wastewater and waste on the neighbourhood level, offers one possible solution to the challenges imposed by rapid urbanisation and growing resource needs. The change from centralised to semicentralised supply and treatment systems will minimise the grave discrepancy between the rapid urban growth and the provision of supply and treatment infrastructure. Integrated semicentralised supply and treatment systems face the challenge of growing amounts of wastewater and solid waste combined with rising needs of water for private households and industrial use. The semicentralised approach offers a wide range of flexibility in implementation, energy self-sufficient operation, enormous saving potentials in water demands through intra-urban water reuse and further more advantages in comparison to centralised sectored solutions as practised today.

Wastewater as a Source of Energy, Nutrients, and Service Water

With improving analytical techniques, it becomes more and more obvious that municipal wastewater represents a multisubstance mixture containing probably several hundreds of different substances. However, wastewater consists of H2O to more than 99.5%, a purity which many purchasable products will never reach. This means that potentially valuable substances are present in extreme dilution, in concentrations of mg l−1 down to ng l−1, and mixed with all sorts of other substances. The chapter follows these aspects and faces the ambivalent questions: (1) What prerequisite the wastewater has to fulfill to become a resource? (2) Under which conditions wastewater gets a valuable substance instead of a pollutant?

Organising Capacity — Regionale Handlungsfähigkeit von Regionen im demographischen Wandel

KurzfassungDer demographische Wandel stellt Regionen vor große Herausforderungen und (Verteilungs-) Konflikte, für deren Lösung sie zunehmend auf die kooperative Zusammenarbeit mit anderen Gebietskörperschaften sowie mit Akteuren aus Wirtschaft und Zivilgesellschaft angewiesen sind. Das erweiterte Akteursspektrum führt dabei zu einer verstärkt auf Kooperation ausgerichteten regionalen Steuerung auf netzwerkartiger Basis (Regional Governance). Regional Governance hat — vor dem Hintergrund des demographischen Wandels — zum Ziel, Prozesse der Selbstorganisation zu initiieren, d.h. die selbstständige regionale Handlungsfähigkeit herzustellen und eine bessere Selbstorganisation der Region und ihrer Teilräume zu gewährleisten. Für die Herstellung der regionalen Handlungsfähigkeit zeigt der folgende Beitrag am Beispiel der Region Braunschweig die Entwicklung einer „Organising Capacity” auf.AbstractDemographic change is currently posing major challenges for regions and facing them with conflicts (especially regarding the distribution of infrastructure) which call increasingly for co-operative solutions involving other territorial authorities as well as the involvement of the private sector and civil society. This broadening of the range of actors involved in turn requires a form of network-based regional governance geared increasingly to promoting cooperation. Against the background of demographic change, Regional Governance aims to initiate processes of self-organisation, i.e. to create the capacity to act autonomously at regional level, and to improve the self-organising capacity to both sub-regions and of a region in its entirety. In order to show how this capacity to act at regional level might be established, the following article takes the Braunschweig region as a case in point to illustrate the development of this type of „organising capacity”.

Urban semicentralised supply and disposal: innovations and challenges for Hanoi, Vietnam

The development of the world population is characterised by two trends: absolute population growth and rapid urbanisation. In the urban region of Hanoi, the capital of the Socialist Republic of Vietnam, extensive urbanisation contributes to a deficient provision of infrastructure causing environmental degradation and health problems for large parts of the population. The protection of the environment, as well as the preservation of historic urban fabric, requires new approaches to infrastructure supply. The semicentralised approach, focusing on supply and treatment structures on the neighbourhood level, offers a solution to the challenges imposed by urbanisation. Contrasting existing plans for conventional centralised sewerage systems in Hanoi, it allows the closing of certain cycles on a local level. Within an integrated approach local technologies, such as septic tanks, can be used further on. As it is process oriented, existing management structures of waste and wastewater treatment are to be considered and incorporated.

Potenziale flexibler integrierter semizentraler Infrastruktursysteme in der Siedlungswasserwirtschaft

ZusammenfassungDynamische Rahmenbedingungen wie der demographische Wandel oder der Klimawandel erfordern eine Flexibilität, die bestehende Infrastruktursysteme nur schwerlich gewährleisten können. Die bisherige Annahme, dass zentrale Systeme bei mittleren bis hohen Siedlungsdichten technische und ökonomische Vorteile gegenüber dezentralen Systemen haben, muss vor dem Hintergrund der erforderlichen Anpassungsfähigkeit in Frage gestellt werden. Der vorliegende Beitrag stellt einen innovativen Ansatz integrierter Infrastrukturlösungen vor, der ursprünglich für schnell wachsende urbane Räume Asiens entwickelt wurde. Vor dem Hintergrund sich verändernder Rahmenbedingungen und dem bestehenden Investitionskostenrückstand in Deutschland wird die Übertragbarkeit dieses Ansatzes bzw. einzelner Komponenten davon kritisch überprüft. Handlungsoptionen für die Anpassung bestehender Infrastruktursysteme der Siedlungswasserwirtschaft in der Bundesrepublik werden abgeleitet und Anpassungsstrategien aufgezeigt.AbstractDynamics like climate or demographic changes require a new flexibility, which existing infrastructure systems in Germany cannot perform. The general assumption centralized systems within urban areas of middle or high density offer advantages compared to decentralized structures has to be scrutinized under changing conditions. The following paper introduces an innovative approach of integrated, sector crossing infrastructure systems developed for fast growing urban areas in Asia and screens for transfer potentials of this approach, in order to develop strategies to cope with arising problems in infrastructure matters in Germany. The paper closes with strategic recommendations for changing infrastructure development and offers strategies for adapting current infrastructure elements in order to perform better under changing conditions.