title: The evaluation of rainfall influence on combined sewer overflows characteristics: the Berlin case study.
abstract: The present study aims to explore the relationship between rainfall variables and water quality/quantity characteristics of combined sewer overflows (CSOs), by the use of multivariate statistical methods and online measurements at a principal CSO outlet in Berlin (Germany). Canonical correlation results showed that the maximum and average rainfall intensities are the most influential variables to describe CSO water quantity and pollutant loads whereas the duration of the rainfall event and the rain depth seem to be the most influential variables to describe CSO pollutant concentrations. The analysis of partial least squares (PLS) regression models confirms the findings of the canonical correlation and highlights three main influences of rainfall on CSO characteristics: (i) CSO water quantity characteristics are mainly influenced by the maximal rainfall intensities, (ii) CSO pollutant concentrations were found to be mostly associated with duration of the rainfall and (iii) pollutant loads seemed to be principally influenced by dry weather duration before the rainfall event. The prediction quality of PLS models is rather low (R² < 0.6) but results can be useful to explore qualitatively the influence of rainfall on CSO characteristics.
authors.affiliation: Grupo de Investigación Ciencia e Ingeniería del Agua y el Ambiente, Facultad de Ingeniería, Pontificia Universidad Javeriana, Edificio J.G. Maldonado, S.J., Carrera 7 No. 40-62, Bogotá, Colombia.
authors.forename: S
authors.initials: S
authors.lastname: Sandoval
authors.affiliation: Grupo de Investigación Ciencia e Ingeniería del Agua y el Ambiente, Facultad de Ingeniería, Pontificia Universidad Javeriana, Edificio J.G. Maldonado, S.J., Carrera 7 No. 40-62, Bogotá, Colombia.
authors.forename: A
authors.initials: A
authors.lastname: Torres
authors.affiliation: Berliner Wasserbetriebe, Netz- und Anlagenbau, Neue Jüdenstrasse 1, 10864 Berlin, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Pawlowsky-Reusing
authors.affiliation: Kompetenzzentrum Wasser Berlin gGmbH, Cicerostraße 24, 10709 Berlin, Germany E-mail: nicolas.caradot@kompetenz-wasser.de.
authors.forename: M
authors.initials: M
authors.lastname: Riechel
authors.affiliation: Kompetenzzentrum Wasser Berlin gGmbH, Cicerostraße 24, 10709 Berlin, Germany E-mail: nicolas.caradot@kompetenz-wasser.de.
authors.forename: N
authors.initials: N
authors.lastname: Caradot
mesh_terms: D002947:Cities; D004784:Environmental Monitoring / Q000379:methods* / Q000706:statistics & numerical data*; D005858:Germany; D057446:Hydrodynamics; D016018:Least-Squares Analysis; D015999:Multivariate Analysis; D011891:Rain; D012722:Sewage; D014873:Water Pollutants / Q000032:analysis*; D060753:Water Quality
chemical_list: D012722:Sewage; D014873:Water Pollutants