BlueM is a software package for river basin management. It allows for the integrated simulation, analysis and optimisation of discharge and pollution loads in rural and urban catchments, including processes in the water body, using physically-based hydrologic approaches. BlueM is the result of continuous development efforts based on model concepts that have been pursued at ihwb for many years and have already been implemented in various applications.

Besides the hydrological model core for rainfall-runoff computations including discharge, pollution load and water quality processes in rural and urban catchments (BlueM.Sim), the BlueM software package also contains tools for visualizing and analyzing time series (BlueM.Wave), for optimizing, auto-calibrating and performing sensitivity analyses on model parameters (BlueM.Opt), as well as for visualizing optimization results (e.g. in the form of scatterplot matrices). A further package component is BlueM.Analyser, a tool for carrying out monitoring and assessment tasks in real-time (per time step).

BlueM.Sim and BlueM.Analyser are equipped with OpenMI-interfaces, which allows them to be coupled with other OpenMI-compliant models.

BlueM components:

• BlueM.Sim (hydrologic computational core – with OpenMI-interface)
• BlueM.Wave (time series management and analysis tool)
• BlueM.Opt (optimization based on evolutionary algorithms and sensitivity analysis)
• BlueM.Analyser (real-time data monitoring and evaluation tool – coupled via OpenMI)

The software package BlueM is freely available after registration. It is also possible to access the source code for research purposes (requires an aggreement with ihwb). Further information can be found on http://www.bluemodel.org.

Extensive investigations in recent years and decades not only demonstrate very clearly the dependence of human well-being on intact ecosystems, but also their immense economic importance. Especially in the context of international development it could be shown, that even short term resource over use has not lead to long lasting well-being, but possibly to irrevocable loss of valuable ecosystems.

Furthermore avoiding overexploitation is more favorable and simpler than recuperation of functioning ecosystems. Complementary to this insight efficient and practicable financing mechanisms for a sustainable natural resource use as a basis for a socio-economic development are still lacking.

Very promising seem in this context concepts of Payments for Ecosystem Services (PES). These are experiencing increasing popularity, because they address a still unsolved problem: the integration of externalities in resource use.

This research refers directly to the above mentioned Payments for Ecosystem Services and their potential to reach the following goals:

• sustainable environmental conservation and protection i.e. reestablishment of the natural capital and its ecological function,
• poverty reduction, and
• promotion of a participatory Integrated Land and Water Resource Management as well as a sustainable spatial planning progress.

Hereby shall be investigated in particular the influence of different land uses on the provision of hydrological ecosystem services (physical relationship). Especially the possibility of combining environmental protection with poverty reduction in developing countries through sustainable forestry and agriculture in relation to PES will be investigated concerning synergies, complementarity and competition of the respective objectives. Finally the development of decision support systems for an integrated assessment of these natural services shall be promoted.

Catchments are typically formed by a patchwork of urbanized, agricultural and natural areas. Figure 1 outlines sub-systems of such a catchment. It comprises urban areas with sewer systems and wastewater treatment plants (WWTPs), rural parts with natural or agricultural areas and the receiving water body.

Most integrated model approaches in the field of urban drainage consider only one sewer system and WWTP in detail. Flow and pollution information stemming from upstream agricultural, natural or urban areas are normally considered in a simplified manner and not modelled explicitly. In contrast, the representation of urban areas is not possible in most models for diffuse sources and if, urban impacts are represented in a simplified manner.

An integrated approach for catchment wide modelling is developed. The approach is based on different models for the sub systems of a river basin: Multiple urban areas including respective sewer systems, combined sewer overflows and waste water treatment plants; rural catchments with natural or agricultural sub areas and the river body itself. Impacts on water quality from all sub systems are considered including diffuse pollution sources from agricultural and natural areas.

During the lifetime of a reservoir its boundary conditions are continuously changing. Such changes include global changes such as climate and economic change as well as national, regional and local changes. National changes are often induced by modified political objectives, regional changes might include supply and demand alterations, while local changes include modifications directly linked to the reservoir infrastructure itself. It must be the objective to be prepared for such changes by analysing the consequences of potential future changes, defined by a set a feasible scenarios (multiple futures).

In this research BlueM, a model developed by the Institute for Hydraulics and Water Resources Engineering, Section for Hydrology and Water Management of the Darmstadt University of Technology, Germany, will be used to analyses future development of water resources yield and demand and related potential future modifications of the infrastructure and its operation for the case of Aswan high dam reservoir.

Within the framework of the RIMAX (Risk Management of Extreme Flood Events) research activity funded by the Federal Ministry of Education and Research, we are working on the project "Improvement of dam safety and reduction of flood risk for downstream river sections using optimized operating rules for reservoirs and polders under consideration of ecological aspects ".

Currently, new approaches for a more thorough consideration of ecological aspects in the development of flood control concepts are under discussion, which, in the medium term, can be expected to be implemented in line with the EU Water Framework Directive. At the same time, it must be ensured that the new operating concepts do not impair the safety of the dams, or better yet, that dam safety is improved, where necessary.

This research project aims to develop the framework of a suitable tool for analyzing flood control systems in low mountain ranges and adjacent transitional stretches that are significantly affected by dams. This methodology comprises coupled monitoring and model systems that allow for the development of dynamic operating strategies, which, ultimately, can render obsolete the hitherto common practice of treating operating rules and real-time control separately.

Our project partner, the Institute for Hydraulic Engineering and Applied Hydromechanics of TU Dresden deals with the management of flood control storage areas downstream of dams. The case study for this project is the reservoir system on the Rur River in Western Germany, managed by the Wasserverband Eifel-Rur .