DOI: 10.5281/zenodo.15783831
title: Continuous sewer hydraulic and pollutant concentration observations from 2008 to 2011 including precipitation data, laboratory analysis and a hydrodynamic model

description: This dataset compiles continuous hydraulic and water quality observations from the combined sewer overflow structure at the outlet of the Graz-West R05 catchment in Austria, covering the period from 2008 to 2011. It integrates high-resolution in-sewer measurements of flow rate, water level, flow velocity and water quality parameters (COD, TSS, temperature), complemented by laboratory analyses of discrete grab samples. Water quality parameters were monitored using an in-situ UV/VIS spectrometer installed on a floating pontoon. Additional locally calibrated COD values derived from laboratory measurements are included. The in-sewer data were acquired at 1- or 3-minute intervals depending on flow conditions.  Flow rates, water levels and overflow discharges were monitored using radar and ultrasonic sensors. Three nearby tipping-bucket rain gauges provided time-stamped precipitation increments, enabling the detailed reconstruction of wet-weather dynamics. All recorded time series are stored in standardised CSV formats with ISO-conform timestamps, along with accompanying metadata that specifies instrumentation, units, data gaps, measurement principles and calibration states. A hydrodynamic SWMM model of the catchment, including geospatial information and dry-weather calibration, is included to support modelling applications.

 

 

 
description: Data collection

Hydraulic data were obtained with a radar-based flow meter (FloDar, Hach/Marsh McBirney), an ultrasonic flow meter (Nivus, OCM Pro) and ultrasonic water-level sensors (Sommer) installed in the inflow conduit, chamber and overflow conduit, logged at 1- and 3-min intervals. Pollutant concentrations were monitored with an UV/VIS probe (s::can, spectro::lyser, 200-750 nm, measurement path of 5 mm) mounted on a floating pontoon. Corresponding grab samples were collected by an automatic peristaltic sampler (American Sigma/Hach) and analysed for COD and TSS in the laboratory. Rainfall was recorded by three tipping-bucket gauges (0.1 mm resolution, Young 52202).
description: Value of the Data



The dataset provides three years of high-quality, high-resolution continuous measurements (hydraulics, precipitation, pollutant concentrations) drawn from a 20-year monitoring programme of a combined sewer overflow system - offering rare, temporally detailed insight into the behaviour of urban drainage systems.

It enables the robust analysis of the interlinking of rainfall, flow dynamics and pollutant loads, including the triggering of pollutant flush events by rainfall — which is essential for understanding how water quality responds to real weather conditions.

The combination of measured data and an existing sewer model enables researchers to develop and test new pollutant transport models (e.g. statistical or machine learning based).

Practitioners and engineers can use the data to design and evaluate retention or mitigation measures for combined sewer overflows, thus supporting informed infrastructure planning and management.

Because the dataset originates from a real long-term case study, it can serve as a teaching tool, helping students and early career researchers practice calibration and validation workflows using authentic urban hydrology data.