Robert Sämann

TL;DR: In this article, a Lagrangean particle-based transport model is introduced to calculate the potential contamination paths of solutes in drainage water in an urban area during a pluvial flood event.

TL;DR: In this paper, a particle-based transport model for fast prediction of travel paths of contaminants after a spill during a flash flood is implemented, which calculates mixing and dispersion in the pipe system and on the surface by using a random walk approach.

Abstract: In case of heavy pluvial rain events in urban areas the available drainage system could be insufficient at peak flows (Sunkpho, 2011). Consequently, rainwater in the pipe network is likely to spill out through manholes, causing inundation. The presence of hazardous contaminants in the pipe drainage system, for example due to an accident with dangerous substances, represents a potential risk to humans especially when the contaminated drainage water reaches the surface. For the prediction of transport paths and risk mitigation, a real-time forecasting model of contaminants in the drainage system is required, which needs small computation cost for quick calculation and sufficient warning time. A particle based pollutant transport model based on precalculated velocity fields in an urban catchment can be used to forecast transport paths and contamination area of a single point source pollution. As the velocity field on the surface and in the pipe system is very dynamic in such scenarios, the riskmaps are sensitive to time and location of the spill event (Sämann, 2018). With an ensemble of velocity fields, chosen with a nearest neighbor criteria of the rainfall characteristics, the pollution affected area can be approximated if the real velocity field has not yet been calculated during the forecast process.

TL;DR: In this paper, the authors introduced and compared four distance metrics for temporal rainfall patterns used in a nearest neighbor based forecast system for dynamic water levels and velocities during pluvial floods.