The Revitalised FSR/FEH Rainfall- Runoff Method · 2019. 6. 29. · PC on which the spreadsheet is...
Transcript of The Revitalised FSR/FEH Rainfall- Runoff Method · 2019. 6. 29. · PC on which the spreadsheet is...
The Revitalised FSR/FEH Rainfall-
Runoff Method
User guidance to Spreadsheet implementation of the Revitalised FEH
Rainfall-Runoff method
Version 1.3 Centre for Ecology & Hydrology, Wallingford December 2005
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Disclaimer CEH (a component body of the Natural Environment Research Council) is not able to warrant the accuracy of the data, software or handbook supplied to the user, and indeed has no responsibility for determining the fitness of the data, software or handbook for their intended use by the user. The provision of such data carries no liability for its accuracy or reliability or any omissions, and we cannot be held accountable for any loss, damage, injury (other than death or personal injury) or any other occurrence arising from the use of the data, software or handbook. Our entire liability in respect of any tort or breach of our duties, statutory or otherwise, whether or not attributable to our negligence, is limited to fee you have paid for the data, software & handbook. It must be recognised that raw data may be transcribed, or may be acquired and processed using automated techniques. Although such processing is made subject to quality-control procedures, so as to ensure reliability where possible, some data may be subject to processing without human intervention with the result that errors may be undetected.
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Acknowledgements The revitalised FSR/FEH rainfall-runoff method is the outcome of a joint
Defra/Environment Agency funded research project (FD1913) undertaken at the Centre
for Ecology & Hydrology. The research team would like to thank the following people
and organisations for giving their time to test and give valuable feedback on a beta
version of the present spreadsheet model.
Peter Spencer and Jean Frost Environment Agency Paul Webster Hydro-Logic Ltd David MacDonald Black & Veatch Rob Lamb and Kate Durr JBA Consulting Luke Lovell Halcrow Sonja Folwell Centre for Ecology & Hydrology
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Table of content 1. Introduction…………………………………………………………………….. 1
2. Installation…………………………………………………………………….... 2
3. Getting started………………………………………………………………….. 3
4. Project sheet…………………………………………………………………….. 5
5. Catchment sheet………………………………………………………………… 7
6. Rainfall sheet……………………………………………………………………. 9
7. Model sheet……………………………………………………………………… 11
8. Results sheet…………………………………………………………………….. 13
9. Audit sheet………………………………………………………………………. 15
10. Additional information………………………………………………………... 17
11. References 18
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1. Introduction
The current spreadsheet has been created to disseminate the results from the joint
Defra/Environment Agency funded research project FD1913 Revitalisation of the
FSR/FEH rainfall-runoff method (Kjeldsen et al. 2005). This spreadsheet is a user-
friendly implementation of the method to be applied for design flood estimation in the
UK. The spreadsheet application is found in the EXCEL file ReFH Rainfall-Runoff
Method.xls.
The spreadsheet allows the input data and output results to be graphed easily and can be
used to produce and print reports simply and quickly.
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2. Installation
To use the spreadsheet it is necessary to have Excel (version 97 or later) installed on any
PC on which the spreadsheet is to be used.
To install the spreadsheet, double-click the file ‘setup.exe’ and follow the instructions.
The two files (ReFH Rainfall-Runoff Method.xls and FEHRRModel.dll) will be installed
in the directory Program Files\FEH Software\ReFH Spreadsheet. A shortcut to the
spreadsheet will be placed on the desktop.
Following installation, multiple copies of the spreadsheet can be made and stored
anywhere on the PC or network. However, if the spreadsheet is to be applied on a PC
other than the one where it was originally installed, the installation program must be run
again in order to provide access to the library functions.
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3. Getting started
To use the spreadsheet, open it in Excel. Excel may notify the user that the file contains
macros, as in the picture below.
In order for the model to run, it is necessary to enable these macros to be run. Some
instances of Excel may have macros completely turned off. In this case the settings in
EXCEL must be changed for the macros to be run (through the Tools | Options menu
item and the Macro Security button on the Security tab within Excel 2002).
The spreadsheet consists of 5 core-sheets (Catchment, Rainfall, Models, Results and
Audit) allowing the catchment and model parameters to be set up and the results viewed.
Within these sheets catchment descriptors can be imported and design rainfall and model
parameters can be set, altered and overwritten. Having calibrated the Revitalised flood
hydrograph (ReFH) rainfall-runoff model, the specified design flood hydrograph can be
generated and the results viewed on the Results sheet. Values for model parameters can
be adjusted and the effect on results viewed immediately.
Following successful setup and application of the design method, a report can be
generated and viewed on the Audit sheet. The audit report will provide an audit trail of
the particular application of the revitalised FSR/FEH rainfall-runoff method. The report
contains a summary of the settings used and the model results are presented in both
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tabular and graphic form. In addition users can add their own comments to this audit trail
within each individual sheet.
Many of the cells where model input values are required have been equipped with a
comment box giving guidance on the appropriate value.
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4. Project sheet
The first sheet is the Project sheet where general information can be entered which can
be used to identify specific model applications. This information will be used by the
spreadsheet model in the audit report-writing functionality. The sheet also contains some
instructions on the use of the software and necessary legal limitations. The spreadsheet
can only be used once the disclaimer has been read and understood, and the box at the
bottom of the sheet has been checked.
Fill in the optional user name, project and company boxes as required.
The Clear Results and Clear All buttons can be used to reset spreadsheets for reuse. A
further explanation of the functionality of these two buttons is given in Section 10.
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5. Catchment sheet
The Catchment sheet allows the import, view and edit of catchment details and catchment
descriptors. The simplest way to populate the catchment descriptor fields is to import an
FEH CD-ROM catchment descriptor export file (.csv) or a WINFAP-FEH export file
(.cd) by clicking the Import Catchment Descriptors button. The catchment descriptor
information will then be written to the appropriate locations within the spreadsheet.
All catchment descriptors can be overwritten and any changes to imported values for
descriptors affecting the model output will be noted in the ‘audit trail’ and written to the
Audit sheet.
The name of the catchment can be added to the Catchment name box from where it will
be transferred automatically to the Audit sheet and printed reports.
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Comments can be added to the ‘audit trail’ by entering some text in the Catchment
Comment box and clicking the Add Comment to List button.
Note – exit the Comment box before clicking the Add Comment to List button. The
comment should then appear in the User comments dropdown list. To clear the list, click
the Clear List button.
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6. Rainfall sheet
The Rainfall sheet allows the definition of a design rainfall event according to the FEH
depth-duration-frequency (DDF) model (Faulkner, 1999) combined with the seasonal
correction factor introduced in the revitalised FSR/FEH rainfall-runoff method. To define
a design storm the following parameter values need to be specified
Parameter Description Data type
Time step (hours)* Step by which model is to be incremented Decimal
Duration (hours)* Total length of event Decimal
Return Period (years)** Return period of design rain/flood event Decimal
Season Summer or Winter events can be selected Selection
Seasonal Correction Factor Select ReFH Design Standard or enter value Decimal
Areal Reduction Factor Select ReFH Design Standard or enter value Decimal
*Note – the number of steps or intervals, which is the duration divided by the timestep,
must be an odd integer, and a warning message will advise you if this requirement has
not been met.
** Note – In the Revitalised rainfall-runoff method the T-year flood is generated from the
T-year rainfall, i.e. to produce a 100-year flood, specify a 100-year rainfall event.
In addition, the spreadsheet model uses the catchment average DDF model parameters
(C, D1, D2, D3, E and F) from the Catchment sheet cells B26-B31.
In order for the spreadsheet to produce a T-year event, as specified by the revitalised
FSR/FEH rainfall-runoff method, the default values of the areal reduction factor and the
seasonal correction factor obtained by choosing the ReFH Design Standard option in the
drop down menus should not be altered.
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When correct values have been entered the rainfall event will be calculated and the
resulting design rainfall hyetograph displayed in the graph at the bottom of the sheet.
User comments can be added to the ‘audit trail’ as appropriate using the box and button at
the bottom of the sheet.
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7. Model sheet
The Model sheet allows input of parameter values for the three constituent components of
the ReFH rainfall runoff method; the loss model, the routing model and the baseflow
model.
Options are available for each parameter to allow it to be automatically calculated from
catchment descriptors, set to the ReFH design standard or set by the user manually.
In order for the spreadsheet to produce a T-year event, as specified by the revitalised
FSR/FEH rainfall-runoff method, the default values of Cini, Up, Uk and BF0 obtained by
choosing the ReFH Design Standard option in the drop down menus should not be
altered.
The parameters that can be set by catchment descriptors can also be adjusted by a Donor
correction factor, which can be entered manually. This sets the parameter to the
calculated value multiplied by the correction factor.
Manually editing the Donor Correction Factor or the model parameter will automatically
update the dropdown list.
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User comments can be added to the ‘audit trail’ as appropriate using the boxes and
buttons below each set of model parameters.
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8. Results sheet
When the required parameters have been set, the resulting design flood hydrograph can
be generated from the Results sheet.
Click the Run Model button to fill in the results.
Summaries of the rainfall and model settings can be seen at the top of the sheet. Below
this are the model output data and a graph of key results.
The model settings can be overwritten and, if the changes are valid, the results will be
updated, thereby allowing inspection of the effects of changes to each parameter before
finalising the final model output. Note that when input values calculated from catchment
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descriptors or ReFH design standards are edited in the Result sheet, the new values are
transferred and their status changed in the appropriate dropdown list to ‘User defined’ in
the preceding sheets..
To produce a report on the final settings selected, click the Generate Audit Report button.
This will re-run the model with the specified settings and write the results to the Audit
sheet.
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9. Audit sheet
The Audit sheet provides a full summary of the model parameters selected and the results
within an easily printed black and white report. The summary information is presented at
the top of the report as in the Results sheet. All of the automatically generated and user
added audit information is added at the bottom of the sheet.
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To print the report use Excel’s File | Print or Print Preview menu options.
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10. Additional information
To clear the results and reports click the Clear results button on the Project sheet.
To clear all of the sheets, including the catchment descriptors, click the Clear all button
on the Project sheet.
When the model has been run successfully, it may be useful to save the sheet and all of
the settings. For this purpose it may be found to be useful to keep a blank copy handy for
new model runs.
The appearance of some sheets can be altered if required, though adding additional lines
and columns will invariably cause problems when the model values are read.
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11. References
Faulkner, D. (1999) Rainfall frequency estimation. Flood Estimation Handbook Vol 2,
Institute of Hydrology, Wallingford, UK.
Kjeldsen, T. R., Stewart, E. J., Packman, J. C., Bayliss, A. C. and Folwell, S. (2005)
Revitalisation of the FSR/FEH Rainfall-Runoff method. Final research report to
Defra/EA, Centre for Ecology & Hydrology, Wallingford, UK.