Effect of Spatial Rainfall Distribution on Sewer Flows

1984 ◽  
Vol 16 (8-9) ◽  
pp. 177-188 ◽  
Author(s):  
Wolfgang Schilling
Keyword(s):  
Catchment Area ◽  
Input Data ◽  
Systematic Errors ◽  
Rainfall Event ◽  
Model Parameters ◽  
Rainfall Runoff ◽  
Sewer System ◽  
Rainfall Distribution ◽  
Spatially Homogeneous

Errors in computing flows are caused by uncertainties about input data as well as uncertainties about appropriate models and model parameters. It is investigated how errors of the input “rainfall”, especially errors in spatial resolution, propagate by computation of sewer flows. Results of a case study about a sewer system with a catchment area of 2 km2 and ca. 1000 reaches between manholes show−that mean errors in rainfall event depths of about 20 % occur even with five raingages within or close to the catchment−that the errors by disregarding the spatial distribution are amplified rather than damped by the rainfall-runoff transformation and−that using spatially homogeneous rainfall input for flow computations cause systematic errors due to the wrong assumption of spatially homogeneous initial losses and due to dominating directions of storm movement.

scholarly journals Regionalizing rainfall–runoff model parameters to predict the daily streamflow of ungauged catchments in the dry tropics

2009 ◽  
Vol 40 (5) ◽  
pp. 433-444 ◽  
Author(s):  
David A. Post
Keyword(s):  
Input Data ◽  
Water Yield ◽  
Model Parameters ◽  
Rainfall Runoff ◽  
Wet Season ◽  
Daily Streamflow ◽  
Total Length ◽  
Dry Tropics ◽  
Rainfall Runoff Model ◽  
Runoff Model

A methodology has been derived which allows an estimate to be made of the daily streamflow at any point within the Burdekin catchment in the dry tropics of Australia. The input data requirements are daily rainfall (to drive the rainfall–runoff model) and mean average wet season rainfall, total length of streams, percent cropping and percent forest in the catchment (to regionalize the parameters of the rainfall–runoff model). The method is based on the use of a simple, lumped parameter rainfall–runoff model, IHACRES (Identification of unit Hydrographs And Component flows from Rainfall, Evaporation and Streamflow data). Of the five parameters in the model, three have been set to constants to reflect regional conditions while the other two have been related to physio-climatic attributes of the catchment under consideration. The parameter defining total catchment water yield (c) has been estimated based on the mean average wet season rainfall, while the streamflow recession time constant (τ) has been estimated based on the total length of streams, percent cropping and percent forest in the catchment. These relationships have been shown to be applicable over a range of scales from 68–130,146 km2. However, three separate relationships were required to define c in the three major physiographic regions of the Burdekin: the upper Burdekin, Bowen and Suttor/lower Burdekin. The invariance of the relationships with scale indicates that the dominant processes may be similar across a range of scales. The fact that different relationships were required for each of the three major regions indicates the geographic limitations of this regionalization approach. For most of the 24 gauged catchments within the Burdekin the regionalized rainfall–runoff models were nearly as good as or better than the rainfall–runoff models calibrated to the observed streamflow. In addition, models often performed better over the simulation period than the calibration period. This indicates that future improvements in regionalization should focus on improving the quality of input data and rainfall–runoff model conceptualization rather than on the regionalization procedure per se.

scholarly journals Possibility of Using Selected Rainfall-Runoff Models for Determining the Design Hydrograph in Mountainous Catchments: A Case Study in Poland

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1450 ◽  
Author(s):  
Dariusz Młyński ◽  
Andrzej Wałęga ◽  
Leszek Książek ◽  
Jacek Florek ◽  
Andrea Petroselli
Keyword(s):  
Catchment Area ◽  
Peak Flow ◽  
Rainfall Runoff ◽  
Peak Flows ◽  
Mountainous Catchment ◽  
Mountainous Catchments ◽  
Relative Errors ◽  
Runoff Hydrographs

The aim of the study was to analyze the possibility of using selected rainfall-runoff models to determine the design hydrograph and the related peak flow in a mountainous catchment. The basis for the study was the observed series of hydrometeorological data for the Grajcarek catchment area (Poland) for the years 1981–2014. The analysis was carried out in the following stages: verification of hydrometeorological data; determination of the design rainfall; and determination of runoff hydrographs with the following rainfall-runoff models: Snyder, NRCS-UH, and EBA4SUB. The conducted research allowed the conclusion that the EBA4SUB model may be an alternative to other models in determining the design hydrograph in ungauged mountainous catchments. This is evidenced by the lower values of relative errors in the estimation of peak flows with an assumed frequency for the EBA4SUB model, as compared to Snyder and NRCS-UH.

scholarly journals Identification of Hydrologic Models, Optimized Parameters, and Rainfall Inputs Consistent with In Situ Streamflow and Rainfall and Remotely Sensed Soil Moisture

2018 ◽  
Vol 19 (8) ◽  
pp. 1305-1320 ◽  
Author(s):  
Ashley J. Wright ◽  
Jeffrey P. Walker ◽  
Valentijn R. N. Pauwels
Keyword(s):  
Time Series ◽  
Soil Moisture ◽  
Input Data ◽  
Remotely Sensed ◽  
Model Parameters ◽  
Rainfall Time Series ◽  
Hydrological Models ◽  
Rainfall Runoff ◽  
Model Input ◽  
Rainfall Estimates

Abstract An increased understanding of the uncertainties present in rainfall time series can lead to improved confidence in both short- and long-term streamflow forecasts. This study presents an analysis that considers errors arising from model input data, model structure, model parameters, and model states with the objective of finding a self-consistent set that includes hydrological models, model parameters, streamflow, remotely sensed (RS) soil moisture (SM), and rainfall. This methodology can be used by hydrologists to aid model and satellite selection. Taking advantage of model input data reduction and model inversion techniques, this study uses a previously developed methodology to estimate areal rainfall time series for the study catchment of Warwick, Australia, for multiple rainfall–runoff models. RS SM observations from the Soil Moisture Ocean Salinity (SMOS) and Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) satellites were assimilated into three different rainfall–runoff models using an ensemble Kalman filter (EnKF). Innovations resulting from the observed and predicted SM were analyzed for Gaussianity. The findings demonstrate that consistency between hydrological models, model parameters, streamflow, RS SM, and rainfall can be found. Joint estimation of rainfall time series and model parameters consistently improved streamflow simulations. For all models rainfall estimates are less than the observed rainfall, and rainfall estimates obtained using the Sacramento Soil Moisture Accounting (SAC-SMA) model are the most consistent with gauge-based observations. The SAC-SMA model simulates streamflow that is most consistent with observations. EnKF innovations obtained when SMOS RS SM observations were assimilated into the SAC-SMA model demonstrate consistency between SM products.

scholarly journals Use of Multicriteria Analysis Method DEXi to Define Priorities in Implementation of Irrigation Plans

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 663 ◽  
Author(s):  
Barbara Karleuša ◽  
Andreja Hajdinger ◽  
Lidija Tadić
Keyword(s):  
Environmental Protection ◽  
Catchment Area ◽  
Input Data ◽  
Social Economic ◽  
Multicriteria Analysis ◽  
Analysis Method ◽  
Importance Weight ◽  
Case Study Area ◽  
Criteria Importance

Methodology for determining priorities in implementing irrigation plans using multicriteria analysis method DEXi is applied on the specific case study area in the sub-catchment area of river Orljava in Požega-Slavonia County, Croatia. Five potential irrigation areas are analyzed according to five selected criteria: environmental protection, water-related (4 sub-criteria), social, economic and time criteria with different criteria importance (weight). The aims of this paper are: confirm the adequacy of using DEXi method when determining priorities in fulfilling irrigation plans; present the model for preparation of the input data; apply the method and give feedback on the application.

scholarly journals Advanced sensitivity analysis of the impact of the temporal distribution and intensity in a rainfall event on hydrograph parameters in urban catchments: a case study

2021 ◽  
Author(s):  
Francesco Fatone ◽  
Bartosz Szelag ◽  
Adam Kiczko ◽  
Darek Majerek ◽  
Monika Majewska ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Hydrodynamic Model ◽  
Estimation Method ◽  
Temporal Distribution ◽  
Rainfall Event ◽  
Model Parameters ◽  
Rainfall Distribution ◽  
Urban Catchments ◽  
Outflow Hydrograph ◽  
The Impact

Abstract. Knowledge of the variability of the hydrograph of outflow from urban catchments is highly important for measurements and evaluation of the operation of sewer networks. Currently, hydrodynamic models are most frequently used for hydrograph modeling. Since a large number of their parameters have to be identified, there may be problems at the calibration stage. Hence, the sensitivity analysis is used to limit the number of parameters. However, the current sensitivity analysis methods ignore the effect of the temporal distribution and intensity of precipitation in a rainfall event on the catchment outflow hydrograph. The article presents the methodology of construction of a simulator of catchment outflow hydrograph parameters (volume, maximum flow). For this purpose, uncertainty analysis results obtained with the use of the GLUE (Generalized Likelihood Uncertainty Estimation) method were used. An innovative sensitivity coefficient has been proposed to study the impact of the variability of hydrodynamic model parameters depending on rainfall distribution, rainfall genesis (in the Chomicz scale), and uncertainty of estimated simulator coefficients on the parameters of the outflow hydrograph. The results indicated a considerable influence of rainfall distribution and intensity on the sensitivity factors. The greater the intensity and temporal distribution of rainfall, the lower the impact of the identified hydrodynamic model parameters on the hydrograph parameters. Additionally, the calculations confirmed the significant impact of the uncertainty of the estimated coefficient in the simulator on the sensitivity coefficients, which has a significant effect on the interpretation of the relationships obtained. The approach presented in the study can be widely applied at the model calibration stage and for appropriate selection of hydrographs for identification and validation of model parameters.

scholarly journals Study on the Improved Method of Urban Subcatchments Division Based on Aspect and Slope- Taking SWMM Model as Example

Hydrology ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 26
Author(s):  
Zening Wu ◽  
Bingyan Ma ◽  
Huiliang Wang ◽  
Caihong Hu
Keyword(s):  
Catchment Area ◽  
Current Method ◽  
Model Parameters ◽  
Rainfall Runoff ◽  
Storm Water Management Model ◽  
Digital Elevation ◽  
Catchment Areas ◽  
Average Slope ◽  
Elevation Model ◽  
Swmm Model

The storm water management model (SWMM) is widely used in urban rainfall runoff simulations, but there are no clear rules for the division of its sub catchment areas. At present, the popular sub catchment area division method takes the average slope as the slope parameter of the sub catchment area, which brings errors to the model in mechanism. Based on the current method, this paper proposes a new method to further subdivide the sub catchment area of the SWMM model, according to the Digital Elevation Model (DEM) data of underlying surface, slope and aspect information. By comparing with the previous methods, it was found that the division method based on slope and aspect can make the setting of model parameters and hydraulic exchange conditions clearer, and improve the accuracy of the model on a certain level.

GIS-based applications of sensitivity analysis for sewer models

2012 ◽  
Vol 65 (7) ◽  
pp. 1215-1222 ◽  
Author(s):  
M. Mair ◽  
R. Sitzenfrei ◽  
M. Kleidorfer ◽  
M. Möderl ◽  
W. Rauch
Keyword(s):  
Sensitivity Analysis ◽  
Spatial Dimension ◽  
Model Parameters ◽  
Sewer System ◽  
Environmental Models ◽  
Sensitivity Indices ◽  
Uncertainty Map ◽  
Gis Software ◽  
The Impact

Sensitivity analysis (SA) evaluates the impact of changes in model parameters on model predictions. Such an analysis is commonly used when developing or applying environmental models to improve the understanding of underlying system behaviours and the impact and interactions of model parameters. The novelty of this paper is a geo-referenced visualization of sensitivity indices for model parameters in a combined sewer model using geographic information system (GIS) software. The result is a collection of maps for each analysis, where sensitivity indices (calculated for model parameters of interest) are illustrated according to a predefined symbology. In this paper, four types of maps (an uncertainty map, calibration map, vulnerability map, and design map) are created for an example case study. This article highlights the advantages and limitations of GIS-based SA of sewer models. The conclusion shows that for all analyzed applications, GIS-based SA is useful for analyzing, discussing and interpreting the model parameter sensitivity and its spatial dimension. The method can lead to a comprehensive view of the sewer system.

Sediment transport under dry weather conditions in a small sewer system

1998 ◽  
Vol 37 (1) ◽  
pp. 155-162
Author(s):  
Flemming Schlütter ◽  
Kjeld Schaarup-Jensen
Keyword(s):  
Sediment Transport ◽  
Field Data ◽  
Field Measurements ◽  
Weather Conditions ◽  
Sewer System ◽  
Transport Models ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Initial Results

Increased knowledge of the processes which govern the transport of solids in sewers is necessary in order to develop more reliable and applicable sediment transport models for sewer systems. Proper validation of these are essential. For that purpose thorough field measurements are imperative. This paper renders initial results obtained in an ongoing case study of a Danish combined sewer system in Frejlev, a small town southwest of Aalborg, Denmark. Field data are presented concerning estimation of the sediment transport during dry weather. Finally, considerations on how to approach numerical modelling is made based on numerical simulations using MOUSE TRAP (DHI 1993).

scholarly journals The Budget as a Basis for Ecological Management of Urbanization Projects. Case Study in Seville, Spain

2021 ◽  
Vol 13 (7) ◽  
pp. 4078
Author(s):  
María Rocío Ruiz-Pérez ◽  
María Desirée Alba-Rodríguez ◽  
Cristina Rivero-Camacho ◽  
Jaime Solís-Guzmán ◽  
Madelyn Marrero
Keyword(s):  
Public Procurement ◽  
Embodied Energy ◽  
Short Term ◽  
Sewer System ◽  
Communication Services ◽  
Concrete Aggregates ◽  
The Public ◽  
Basic Services ◽  
Total Impact

Urbanization projects, understood as those supplying basic services for cities, such as drinking water, sewers, communication services, power, and lighting, are normally short-term extremely scattered actions, and it can be difficult to track their environmental impact. The present article’s main contribution is to employ the project budgets of public urbanization work to provide an instrument for environmental improvement, thereby helping public procurement, including sustainability criteria. Two urban projects in Seville, Spain are studied: the first substitutes existing services, and the second also includes gardens and playgrounds in the street margins. The methodology finds the construction elements that must be controlled in each project from the perspective of three indicators: carbon, water footprints, and embodied energy. The main impacts found are due to only four construction units: concrete, aggregates, asphalt, and ceramic pipes for the sewer system, that represent 70% or more of the total impact in all indicators studied. The public developer can focus procurement on those few elements in order to exert a lower impact and to significantly reduce the environmental burden of urbanization projects.

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