Analysing the Results

The results of all the model runs can be analysed by clicking the '6) Process Results' button. This will read the peak flow results for all reporting subcatchments for all AEPs, temporal patterns and durations and calculate statistics.

Tabular Results Display

The results reported can be tailored by the settings in the Configure Results panel.

ConfigureResults

The subcatchment results grid will display all the flows for each subcatchment for the selected duration and report the average, median and standard deviation of the flows. It will also report the adopted temporal pattern and corresponding flow based on the settings. The final two columns will list all flows and temporal patterns in order of increasing peak flow.

If 'critical duration' is selected in the Duration field, the results of all temporal patterns for the critical duration for each subcatchment will be reported.

Resutls
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ARF Error

An ARF Error (%) will also be populated which reports if the results for a subcatchment may have a partial area effect. That is, if the total area of the subcatchment is significantly less than the area of the entire project then a different ARF may be necessary to correctly assign flows for this subcatchment. This field reports the difference between the ARF for the whole project (based on the area field in the Areal Reduction Factors panel) versus the total contributing area for the subcatchment. However, it does not report the difference in flows resulting from the different ARFs and a Partial Area Check may be necessary to quantify this.

 

Detention Basins

In RAFTS, the flows reported in the table will be the subcatchment peak flow or the peak basin outflow if a basin exists. However, the hydrographs are always the subcatchment outflow. As such, the peak flows in the table may not match the hydrograph peak in the chart for subcatchments with a basin. If you require basin outflow hydrographs, insert a 'dummy' subcatchment downstream.

 

arf_warning

 

Configuring the Subcatchments of Interest

The Refine Subcatchments panel allows the user to select the subcatchments of interest for display of results (in the ALL configuration) and the calculation of statistics. For example, a user may wish to only select the subcatchments that are within a hydraulic model area of interest. This will mean that the temporal pattern analysis (refer below) will be tailored to those subcatchments most of interest to the user.

Individual subcatchments can be un-selected by clicking the corresponding checkbox. The search filter can be used to quickly find subcatchments in a large model. The right click menu offers features including check all, clear all and invert selection.

 

SubsOfInterest

 

Temporal Pattern Analysis

The Temporal Pattern Analysis panel attempts to analyse the results for the current results displayed in the Subcatchment Results panel (which is in turn based on the Subcatchments of Interest and Configure Results panel). It lists the following statistics:

how many rows in the table include a specific TP,
for how many rows was this TP the adopted TP
for what percentage of rows was this TP the adopted TP
what is the average absolute difference between this TP and the mean of all TPs for each row. For example, if you have 4 subcatchments selected in the Refine Subcatchments panel, it will determine the absolute difference between the mean of the peaks and the TP in question for each of the 4 subcatchments and then average them. Thus, the TP with the lowest ‘Average Distance from Mean’ may be the most representative TP to use if you had to select one to represent the adopted TP for the subcatchments.
For how many rows was this TP greater than the mean of all TPs
For how many rows was this TP less than the mean of all TPs

 

These statistics may help a user decide which TPs require modelling is a subsequent hydraulic model.

 

TPAnalysis

 

Comparison TPs

 

The Comparison TPs tool is useful if a user wishes to view differences for subcatchments between a designated TP(s) and the adopted TP. One or more TPs (comma separated) can be added to the text file and the 'Compare to TP(s)' checkbox selected. This will cause a new column to be added to the Subcatchmentt Results grid listing the minimum deviation between flow from the adopted TP and the flow from the nearest of the comparison TP(s). This allows the user to quickly identify if a particular subcatchment may not be well represented by the comparison TPs. The TPs in the Temporal Pattern Analysis grid can easily be added to the Comparison TPs field by right click.

ComparisonTPs

 

Box and Whisker Charts

The peak flow results can also be visualised as box and whisker plots using the 'Box Charts' button. The box charts will display the median (horizontal line), average (star) and first and third quartiles (top and bottom of box). The ends of the whiskers represent the lowest and highest points that are still within 1.5 inter-quartile range (equal to the size of the box). Points that are outside the whiskers shall be plotted as outliers.

The flow corresponding to the adopted temporal pattern (as defined in the settings) are linked by a line chart and labelled with their temporal pattern code and adopted TP flow.

The critical duration is highlighted in yellow.  This corresponds to the highest ensemble mean flow.

 

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Box Charts

 

Multiple events can be compared using the Compare Events panel.

 

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Compare Events (Critical Durations)

 

Hydrograph Charts

The hydrograph for any AEP, subcatchment, duration can also be plotted using the 'Hydrograph Charts' button. The hydrograph associated with the adopted temporal pattern will be displayed as a thicker line with a '(Critical)' suffix in the legend. Rainfall hyetographs can also be displayed using the 'Chart Rainfall' checkbox. The colours of the series can be edited using the Edit button. Labeling of peaks and rainfall values can be tailored via the Options panel.

For XP-RAFTS and WBNM, local hydrographs can be charted by clicking the 'Chart local hydrographs instead' checkbox. For XP-RAFTS, this requires *.loc files to be have been generated by your model. The Adopted TP displayed will still reflect the analysis of the total hydrographs peaks. For WBNM, the local hydrographs are the sum of the Qper and Qimp hydrographs and do not reflect any local storage basins.

 

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Hydrograph and Rainfall Chart

Multiple events can be compared using the Compare Events panel.

 

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Compare Hydrographs (critical durations)