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This data collection includes the Python script used for image processing and analysis as described in the article "Quantification of uncertainties from image processing and analysis in laboratory-scale DNAPL migration experiments evaluated by reflective optical imaging" by Engelmann et al. submitted to Journal "Water" in 2019. Exemplary raw images generated from laboratory-scale tank experiments for DNAPL migration are included as well.
This data collection includes the Python script used for model data preparation, processing and assessment as described in the article "Evaluation of Decentralized, Closely-Spaced Precipitation Water and Treated Wastewater Infiltration" by Händel et al. submitted to Journal "Water" in 2018. Python script input data as generated from Hydrus 2D/3D models as well as resulting plots as used in the previously mentioned article are included.
Stable isotope analysis is widely used in environmental tracer studies, e.g. for groundwater flow and discharge quantification. In this context, this study presents an inexpensive approach for the combined use of deuterium (2H) and oxygen-18 (18O) as active semiartificial groundwater tracers by a direct injection of snowmelt into aquifers. This dual isotope approach takes advantage of isotope signature differences between typical groundwater and precipitation water. Aim of this study is the experimental demonstration on laboratory- and field-scale. For this, two column flow experiments were performed using δ2H and δ18O values of snowmelt for breakthrough detection. The differences of the isotope signature between the snowmelt and groundwater were ∆(δ2H) ≈ 61.0 ‰ and ∆(δ18O) ≈ 8.2 ‰. Breakthrough was observed to be almost congruent to a sodium chloride tracer, indicating conservative transport. The low electrical conductivity (EC) of snowmelt (45 µS/cm, i.e. ∆EC ≈ 486 µS/cm to groundwater) was used as an additional easy-to-measure breakthrough indicator. However, the snowmelt EC breakthrough suffered from a slight retardation due to ion exchange. Based on these results, a push-drift-pull tracer test with snowmelt, additionally labeled with uranine, was realized at the field site Pirna, Germany. In the pull phase, a significant isotopic depletion was observed with peak differences of ∆Peak(δ2H) ≈ 24.2 ‰ and ∆Peak(δ18O) ≈ 3.2 ‰, which equals approx. 40 % of the initial difference. The isotope breakthrough was observed to be almost the same as the breakthrough of uranine indicating conservative behavior, while EC breakthrough was affected by ion exchange again.
Urban pluvial flooding is a growing concern worldwide as consequence of rising urban population and climate change induced increases in heavy rainfall. Easy-to-implement and fast simulation tools are needed to cope with this challenge. This study describes the development of the parsimonious, GPU-accelerated hydraulic model RIM2D for urban pluvial flood simulations. This is achieved by considering the built-up urban area as flow obstacles, and by introducing capacity-based approaches to consider urban drainage by infiltration on pervious surfaces and sewer drainage from roofs and sealed surfaces. The model performance was analyzed by simulating 8 heavy rainfall events in a test area in the city of Dresden, Germany. For these events detailed discharge measurements of sewer discharge are available, providing a unique dataset for evaluating the sewer drainage simulation, which is of high importance for realistic pluvial inundation simulations in urban areas. We show that the model simulates the temporal dynamics of the sewer discharge and the sewer volume within acceptable ranges. Moreover, the erratic variation of the simulated to measured sewer discharge suggests that the deviations from the measurements are caused by the precipitation input rather than the model simplifications. We conclude that RIM2D is a valid tool for urban inundation simulation. Its short simulation runtimes allow probabilistic flood risk assessments and operational flood forecasts.