Thomas Wintgens
The main objective of Work Area 4 is to develop technologies and management options to enhance urban water systems by providing new tools, methods and models for the planning, implementation and operation of enhanced urban water systems. The investigated intervention options will cover the entire urban water cycle from water supply via water use to wastewater disposal and water reuse. The work area will have a strong focus on the needs of the pilot/case study cities and the end-users involved in the project. The work area will generate results applicable in the pilot cities to enable the desired transitions in urban water systems being also relevant for many other application areas in Europe and worldwide.
Work Area 4 will follow the goal to achieve carbon neutral and energy self-dependent urban water systems in the future, researching and improving measures to adapt to global climate change conditions in urban systems aiming at the demonstration and implementation of "no-regret" solutions in the urban water system of tomorrow. Among the intervention options addressed are responses to fluctuations in feed water quality to water supply, demand and leakage reduction, management of extreme stormwater events through application of Sustainable Urban Drainage Systems (SUDS), making wastewater treatment systems more compatible to water reuse, increasing energy efficiency in all parts of the water cycle as well as utilizing the potential for combined heat and power generation.
The TRUST Approach
The Work Area 4 methodology comprises conceptual studies, modeling and simulation as well as experimental investigations in pilot scale on treatment and monitoring technology. The Work Area 4 structure follows the urban water cycle and highlights the focal points "water-energy nexus" and "infrastructure asset management" by cross-cutting activities. The priority topics considered in the Work Area are defined according to the needs of the pilot cities and end-users emerging needs as pointed out by Work Area 1 (roadmaps for transition) and Work Area 2 analysed bottlenecks and points-of-attention in the analysis performed by Work Area 3 approaches and outputs from other relevant completed or ongoing European research projects. The selection of intervention options also considers relevant documents by the Water Supply and Sanitation Technology Platform (e.g. Asset Management for sustainable urban water) and EC Communications (e.g. on water scarcity and drought).

Work Area 4 includes six work packages. While Work Package 4.1 to Work Package 4.3 will focus on aspects of improved planning and more sustainable operation in the "classical" elements of urban water systems, namely "water supply", "water use" and "wastewater and stormwater collection, transport and treatment as well as discharge", Work Package 4.4 will highlight the importance of incorporating alternative water sources in enhanced urban water systems (e.g. by reclamation and reuse of wastewater or stormwater or utilisation of other marginal water sources such as brackish groundwater by desalination). The two "cross-cutting" topics "energy-water nexus" and "infrastructure asset management" are structured into Work Package 4.5 and Work Package 4.6 and will closely interact with the other Work Packages. The intention is to push forward new developments in these areas which will then become applicable in the different urban water system components.