Frontiers of Science and Technology

Gabriela Celani, Olfa Kanoun

• Publisher: De Gruyter
• Year: 2017
• ISBN:
  9783110536263
• Edition: 1
• Topic: Technik & Maschinenbau
• Subtopic: Automatisierung im Maschinenbau

Sponsored by the Alexander von Humbold Stiftung the "Bragfost-Confernce" brings together about 60 outstanding German and Brazilian Scientists to discuss most topical issues in the field of electrical engineering, energy-supply as well as sociological impact of technology. This book presents the most relevant contributions in extended and revised form.

Part 1:Water availability for sustainable development

Steffen Krause, Lisa Bross

Safe and reliable water supply

Abstract: The reliable supply of drinking water in sufficient quality and quantity is decisive for the social and economic development of all municipalities. At the same time, water distribution networks represent one of the greatest assets of a municipality. Therefore, water supply is regarded as one element of the critical infrastructure of society. The protection of the water supply, including ensuring drinking water safety in all situations, is a primary objective for water supply companies. Extraordinary events, such as natural disasters like floods or extreme droughts, can affect water supplies in their functioning. There is a high vulnerability to such extreme events for both the individual components as well as for the overall water supply system. The challenges for small and larger water utilities vary due to different boundary conditions. This paper shows aspects of water safety plans for small scale water utilities as well as organizational aspects for emergency planning for larger water utilities.

Keywords: emergency water supply, risk analysis, water security, small scale water supply, water safety plans

1Introduction

The settlement structure in Germany is very heterogeneous. As a consequence of substantial regional differences in population density and distances between neighboring municipalities, the structure of water utilities in Germany is also very heterogenic. The number of water utilities per administrative district can be regarded as an indicator of the aforementioned regional differences in population density. It is becoming obvious that especially in southern Germany the structure is characterized by a variety of very small water utilities (Figure 1). There are nearly 6000 water utilities in Germany that can be characterized by their annual water production as seen in Figure 2. The annual amount of water delivered by the water utilities in Germany ranges between a few thousand cubic meters up to more than 100 million cubic meters.

The legal framework in which water utilities in Germany are operated comprises health based requirements for drinking water quality, state specific regulations for the provision of fire-fighting water, reliability of services, and recently also the obligation to follow the standards for planning, construction, and operation of water supply systems defined by the German Technical Association for Gas and Water (DVGW). This also includes minimum requirements for operational and organizational structures, qualification, and availability of personnel. This is complemented with legal regulations for corporate management and calculation schemes for fees, which are dependent on the legal form of the water utility. The legal form can be essentially characterized as a public or private water utility.

The aforementioned requirements apply to all water utilities, irrespective of their size. Differences exist only in the frequency and intensity of the surveillance, which is stricter with an increasing amount of water delivered.

German water utilities (WU) are facing various challenges. Among them climate change, demographic change, domestic migration processes, an ageing infrastructure, which result in the need for adaption to those changes and the rehabilitation of water distribution networks. This is intensified by problems in the quality of resources in terms of excessively high nitrate concentrations in groundwater in some parts of Germany, mostly as a consequence of intensive agriculture.

Fig. 1: Number of water utilities in Germany (data source: BBK 2016b, authors’ own graph).

Fig. 2: Size structure of Germany’s water utilities (data source: Statistisches Bundesamt 2013, authors’ own graph).

Demographic change and domestic migration affect various parts of Germany in very different ways. Urban areas are growing as the population moves from the rural areas towards more affluent regions with jobs, infrastructure, and a high standard of living. Additionally, the population is moving from the “new” federal states to the western states. This may result in an undersized water infrastructure in urban areas, as well as oversized water infrastructure in rural areas.

The predicted effects of climate change will lead to drier summers with less groundwater recharge, longer periods of heat, and a wider spread between base and peak demand. The latter is a challenge for the design of water distribution networks. System design according to a high pressure drop in times of peak demand is causing stagnation of the drinking water in the network in periods of normal and low demand. This will increase the danger of bacterial regrowth.

The aforementioned burdens for water supply systems are only one example of the different challenges faced particularly by communities in rural areas. Similar effects exist for other parts of public infrastructure elements, such as roads, medical services, and others. In addition, small treatment systems are disadvantageous by economy of scale and specific costs that are higher than those of large urban systems. Finally, public utilities are competing in recruiting personnel with industries that are offering significantly higher wages. This makes it even harder to find and to bind appropriate employees, in particular in areas of demographic decline.

In the end, this requires a resource and cost efficient management of all public services. An option to increase efficiency that is currently being used by many municipalities is intercommunal cooperation. This ranges from sharing resources to joint management of systems, with or without connection of the networks.

Despite these unfavourable preconditions, it is the obligation of all wa...

Table of contents

• Cover
• Title Page
• Copyright
• Preface
• Contents
• List of Contributors
• Part 1: Water availability for sustainable development
• Part 2: Automation and sensor technologies
• Part 3: Digital Fabrication for the construction industry