Water Reuse

Water scarcity depends on population growth, climate changes, and urbanization. The reuse of treated wastewater is a contribution to the management of limited resources in developing as well as in industrialized countries in the fields of agriculture, urban development, industry, hotels and transport.

Since 2005, the DWA working group BIZ 11.4 “water reuse” with its interdisciplinary experts deals with the improvement of frame conditions for project implementation in the field of design and training capacities. 

• Spokesman 2005 – 2008: Hans Huber, Berching
• Spokesman 2009 – 2014: Prof. Peter Cornel, Darmstadt
• Spokesman since 2015:  Prof. Jens Haberkamp, Münster

This report is intended to provide general guidance for water utilities, consulting engineers and regulatory agencies for planning and expanding non-potable water reuse as an alternative freshwater supply, in particular for agricultural irrigation, urban landscape irrigation and other urban uses, and industrial practices.

It provides an overview regarding relevant regulations and guidelines of water reuse, continues to describe the various aspects of risk management involved in water reuse, and also highlights the various technologies that are applied for water reuse.

Part of the DWA topics Non-Potable Water Reuse is a matrix of commonly used processes of wastewater treatment, which has been elaborated in order to support the selection of the most suitable treatment techniques for several reuse purposes. Each process step was assessed with regard to various aspects such as discharge quality, costs, consumption of material and energy, expenses for maintenance etc..

The assessment matrix considers the following treatment steps for water reuse:

• Mechanical treatment (screening, filtration)
• Ponds, storage and treatment tanks
• UASB, ABR, activated sludge process, trickling filter, helophyte treatment plants
• Downstream filtration/precipitation/flocculation, membrane technology
• Disinfection

The former version [2008] of the assessment matrix is still available in German, French, Spanish, Arabic, Chinese and Farsi on personal request.

Contact: knitschky@dwa.de

„DWA guidance for the practical implementation of water reuse” cover theory and in-practice solutions of water reuse in their interdisciplinary context with 500 slides including four elaborated case studies.

1. Importance of water reuse
2. Regulation and standards
3. Planning and implementation and operation of water reuse projects (project manager, water reuse projects, requirements, organisation, quality assurance)
4. Acceptance (target groups, strategies, lessons learnt)
5. Energy (potential, emissions, climate impact)
6. Hygiene (pathogens, disinfection)
7. Ecology and agriculture (water balance, climate, irrigation)
8. Economic aspects( costs, financing, case studies)
9. Case studies from Tunisia, Bahrain, Jordan and Germany

DWA can offer a whole training package “water reuse” according to your needs. The 2-day seminars “water reuse - overview for practitioners and case studies” and further field trip trainings in Germany.