Research

This research project is a contribution to the project: Adaptation strategies to climate change for Austria's water management: Follow-up study 2024. The contribution consists of trend analyses for floods, surface water supply and low flows, and includes literature studies, method comparison and development, and applications for approx. 800 gauging stations in Austria. Different trend analyses, which take into account serial autocorrelation of discharges, are to be evaluated comparatively and an overall statement is to be synthesised. The research question is to what extent the discharge in Austria has changed in the course of climate change and direct anthropogenic influence, and a quantification of the changes by region, season and catchment size.

The aim of the study is a consistent estimation of a wide range of low-flow characteristics at observed and unobserved river sites in Austria. For this purpose, novel regionalisation models are to be developed and evaluated with regard to their predictive performance at unobserved sites. A nested model is proposed as the model structure, which takes into account low flow (NQ) of different time scales (year, season, month, minimum observed value) in hierarchical form, in order to obtain consistent estimates of derived mean characteristic values and extreme value statistics. The regionalisation aims at a consistent estimation of natural low flows and uses a data set of at most slightly anthropogenically influenced daily flow series with more than 40 years of observations.

The aim of this project is to assess the impact of summer low flows on the remobilization of pollutants from river sediments. The analyses are carried out for eastern Austria, where agricultural input and the predicted risk of climate warming on low flow and water temperature are particularly high. The innovative combination of data-based models with laboratory experiments and water quality monitoring allows an overall assessment of the sediment-related risk of quality impairment along the water network. The added value of the derived information is presented for three selected catchments and discussed with stakeholders with regard to water management relevance. From this, recommendations for future climate scenarios will be developed.