The University City Association clearly struck a chord with its choice of topic and high-calibre speakers and panellists. Toni Hinterdobler, chairman of the University City Association, was delighted with the large turnout of listeners from a wide range of sectors of society.
Prof. Dr. Jürgen Geist from the Chair of Aquatic Systems Biology at the TUM School of Life Sciences in Weihenstephan-Triesdorf gave a keynote speech on the possibilities for keeping our water clean. Problems that have already been successfully solved, such as acidification and nutrient enrichment in water bodies, should encourage us to tackle the solvable challenges of nitrate pollution, cyanobacteria and microplastics. In order to reconcile the different interests in water use and prevent the environmental targets from being missed, the importance of the landscape water balance must be recognised and synergies exploited. Lowering the targets would not be sensible.
Worst-case scenarios are still being exceeded
Prof. Dr. Martin G. Grambow, honorary professor at the Technical University of Munich's School of Engineering and Design in Garching and long-time head of the Water Management and Soil Protection Department at the Bavarian Environment Agency, drew attention to the significant differences in precipitation between southern and northern Bavaria. While groundwater levels continue to fall, heavy rainfall is becoming more frequent. The development of the annual average temperature and groundwater recharge is even worse than predicted in all previous forecasts. In order to secure the supply of drinking water for the future, it is necessary to upgrade the infrastructure, protect groundwater and drinking water across the board, reduce pollution and optimise storage and transfer systems. The creation of sustainable agricultural irrigation structures, the improvement of the landscape water balance and the further development of municipalities into so-called sponge cities are further areas of action that must be accompanied by modern monitoring and management systems as well as fiscal and legal measures to influence behaviour.
During the panel discussion, Bavaria's Environment Minister Thorsten Glauber pointed out that the Free State is supporting local authorities in utilising the sponge function of the soil for better water retention on site with its ‘Guideline for Grants for Water Management Projects’ (RZWas). However, because the sponge function reaches its limits during prolonged rainfall or heavy rain, additional technical flood protection is necessary. In order to finance the many tasks related to water, the Free State should introduce a water cent, even if not everyone is enthusiastic about it. For the average consumer, the water cent would mean additional expenditure of four to five euros per year. Water is a difficult long-term task that cannot be left unresolved.
Graduated water cent for large consumers
Eva Lettenbauer, chairwoman of the Bavarian Green Party, warned that, in view of the bleak forecasts for the coming decades, society must join forces to prevent the ecosystem from collapsing. She criticised the CSU and the Free Voters for talking about introducing the water cent for years without taking any action. The Greens would like to see a tiered water cent that places a greater burden on large consumers. ‘We have to do something to raise the groundwater level again, and we need more money to do that.’
Christoph Kämpf, managing director of the Karmeliten brewery, reported on his brewery's efforts to consume as little water and energy as possible. Thanks to massive investments in modern machinery, the brewery has been able to save around 40 percent of its water consumption compared to the past. Kämpf urged visitors to the event to critically rethink their own water consumption. ‘If every Straubinger reduced their water consumption by ten percent, that would be a huge saving for the city.’
Prof. Dr. Ingrid Kögel-Knabner from the Chair of Soil Science at the TUM School of Life Sciences in Freising emphasised that soil is essential for storing water. The more land is sealed and the more the soil is compacted by heavy machinery, the less water it can store and filter.
Fourth purification stage costs 20 million euros
Cristina Pop, Managing Director of Straubinger Stadtentwässerung und Straßenreinigung (SER), reported on the various measures that Straubing has taken, thanks in part to support from the state government, to renature streams, unseal areas and create new green spaces. Whereas the sewage treatment plant used to consist of a simple rake, the Straubing plant can now even filter nitrogen from the wastewater. In order to achieve even better results, a fourth treatment stage would be useful, but would cost around 20 million euros.
In his closing remarks, Prof. Dr. Volker Sieber, Rector of the Straubing TUM Campus, announced the topic for the fourth Straubing Sustainability Talk next spring: ‘Sustainable food production.’
