Flooding in urban drainage systems: coupling hyperbolic conservation laws for sewer systems and surface flow

The European research project in the EUREKA framework, RisUrSim is presented with its overall objective to develop an integrated planning tool to allow cost effective management for urban drainage systems. The project consortium consisted of industrial mathematics and water engineering research institutes, municipal drainage works as well as an insurance company. The paper relates to the regulatory background of European Standard EN 752 and the need of a more detailed methodology to simulate urban flooding. The analysis of urban flooding caused by surcharged sewers in urban drainage systems leads to the necessity of a dual drainage modeling. A detailed dual drainage simulation model is described based upon hydraulic flow routing procedures for surface flow and pipe flow. Special consideration is given to the interaction between surface and sewer flow during surcharge conditions in order to most accurately compute water levels above ground as a basis for further assessments of possible damage costs. The model application is presented for a small case study in terms of data needs, model verification and first simulation results.

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Parallel computing in conceptual sewer simulations

Water Science & Technology ◽

10.2166/wst.2010.798 ◽

2010 ◽

Vol 61 (2) ◽

pp. 283-291 ◽

Cited By ~ 5

Author(s):

G. Burger ◽

S. Fach ◽

H. Kinzel ◽

W. Rauch

Keyword(s):

Parallel Computing ◽

Software Tool ◽

Computational Time ◽

Limiting Factor ◽

Urban Drainage ◽

Pollution Effects ◽

Drainage Systems ◽

Sewer Systems ◽

Urban Drainage Systems

Integrated urban drainage modelling is used to analyze how existing urban drainage systems respond to particular conditions. Based on these integrated models, researchers and engineers are able to e.g. estimate long-term pollution effects, optimize the behaviour of a system by comparing impacts of different measures on the desired target value or get new insights on systems interactions. Although the use of simplified conceptual models reduces the computational time significantly, searching the enormous vector space that is given by comparing different measures or that the input parameters span, leads to the fact, that computational time is still a limiting factor. Owing to the stagnation of single thread performance in computers and the rising number of cores one needs to adapt algorithms to the parallel nature of the new CPUs to fully utilize the available computing power. In this work a new developed software tool named CD3 for parallel computing in integrated urban drainage systems is introduced. From three investigated parallel strategies two showed promising results and one results in a speedup of up to 4.2 on an eight-way hyperthreaded quad core CPU and shows even for all investigated sewer systems significant run-time reductions.

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Sustainable urban drainage systems: a tool to adapt combined sewer systems to climate change

Proceedings of the Institution of Civil Engineers - Municipal Engineer ◽

10.1680/jmuen.17.00035 ◽

2019 ◽

Vol 172 (3) ◽

pp. 175-184 ◽

Cited By ~ 1

Author(s):

Carlos García-Terán ◽

Iñaki Tejero-Monzón ◽

José Luis Gil-Díaz

Keyword(s):

Climate Change ◽

Urban Drainage ◽

Drainage Systems ◽

Sewer Systems ◽

Combined Sewer ◽

Urban Drainage Systems

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Urban Drainage Systems: Design and Operation

Water Science & Technology ◽

10.2166/wst.1993.0291 ◽

1993 ◽

Vol 27 (12) ◽

pp. 31-70 ◽

Cited By ~ 32

Author(s):

J. Marsalek ◽

T. O. Barnwell ◽

W. Geiger ◽

M. Grottker ◽

W. C. Huber ◽

...

Keyword(s):

Sewage Treatment ◽

Systems Design ◽

Urban Drainage ◽

Sewer System ◽

Drainage Systems ◽

Planning And Design ◽

Sewer Systems ◽

Combined Sewer ◽

Urban Drainage Systems ◽

Receiving Waters

Design and operation of urban drainage systems are addressed in the context of the urban water system comprising drainage, sewage treatment plants and receiving waters. The planning and design of storm sewers are reviewed with reference to planning objectives, design objectives, flows and pollutant loads, sewer system structures and urban runoff control and treatment. The discussion of combined sewers focuses on hydraulic design of combined sewer systems, including combined sewer overflow (CSO) structures, and the use of CSO structures and storage in control of CSOs. The section on operation of sewer systems focuses on real time control, its feasibility, planning, design, operation and applications. Sewer system planning and design are generally conducted using computer modelling tools and procedures which are reviewed in the last section. A brief listing of selected models focuses on internationally used models. Finally, it was concluded that further improvements in environmental and ecological protection of urban waters is feasible only by consideration of urban drainage systems in conjunctions with sewage treatment and water quality in the receiving waters.

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Performance assessment of separate and combined sewer systems in metropolitan areas in southern China

Water Science & Technology ◽

10.2166/wst.2013.732 ◽

2013 ◽

Vol 69 (2) ◽

pp. 422-429 ◽

Cited By ~ 13

Author(s):

Tian Li ◽

Wei Zhang ◽

Cang Feng ◽

Jun Shen

Keyword(s):

Performance Assessment ◽

Metropolitan Areas ◽

Southern China ◽

Drainage System ◽

Practical Experience ◽

Urban Drainage ◽

Drainage Systems ◽

Sewer Systems ◽

Combined Sewer ◽

Urban Drainage Systems

To assess the performance of urban drainage systems in metropolitan areas in southern China, 12 urban drainage systems, including nine separate sewer systems (SSSs) and three combined sewer systems (CSSs) were monitored from 2008 to 2012 in Shanghai and Hefei. Illicit connection rates of SSS were determined. The results indicate that serious illicit connections exist for most SSSs. Annual volume balance for two SSSs with serious illicit connection was assessed with a hydraulic model to determine the dry weather overflow volume. Although interception facilities have been implemented in SSSs, for some systems with serious illicit connections, a considerable volume of dry weather overflow still existed. Combined with monitoring of dry/wet weather flow quality, the pollutant load caused by wet/dry weather overflow was quantified. The results revealed that there was no obvious advantage of having SSSs over CSSs in terms of pollutant control. The serious pollution caused by illicit connections and insufficient management occurs in many cities in China. The performance assessment of separate and CSSs in Shanghai and Hefei provides important lessons and practical experience that can be applied to the construction and management of urban drainage system in China as well as other developing countries.

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Nowcasting of rainfall and of combined sewage flow in urban drainage systems

Water Science & Technology ◽

10.2166/wst.2009.098 ◽

2009 ◽

Vol 59 (6) ◽

pp. 1145-1151 ◽

Cited By ~ 19

Author(s):

Stefan Achleitner ◽

Stefan Fach ◽

Thomas Einfalt ◽

Wolfgang Rauch

Keyword(s):

Spatial Scales ◽

Radar Data ◽

Urban Drainage ◽

Real Time Control ◽

Sewer System ◽

Drainage Systems ◽

Time Control ◽

Sewer Systems ◽

Urban Drainage Systems ◽

The City

Nowcasting of rainfall may be used additionally to online rain measurements to optimize the operation of urban drainage systems. Uncertainties quoted for the rain volume are in the range of 5% to 10% mean square error (MSE), where for rain intensities 45% to 75% MSE are noted. For larger forecast periods up to 3 hours, the uncertainties will increase up to some hundred percents. Combined with the growing number of real time control concepts in sewer systems, rainfall forecast is used more and more in urban drainage systems. Therefore it is of interest how the uncertainties influence the final evaluation of a defined objective function. Uncertainty levels associated with the forecast itself are not necessarily transferable to resulting uncertainties in the catchment's flow dynamics. The aim of this paper is to analyse forecasts of rainfall and specific sewer output variables. For this study the combined sewer system of the city of Linz in the northern part of Austria located on the Danube has been selected. The city itself represents a total area of 96 km2 with 39 municipalities connected. It was found that the available weather radar data leads to large deviations in the forecast for precipitation at forecast horizons larger than 90 minutes. The same is true for sewer variables such a CSO overflow for small sub-catchments. Although the results improve for larger spatial scales, acceptable levels at forecast horizons larger than 90 minutes are not reached.

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