Download SKED_GB-WISKI_UserGuide

The Eta Method
Application of the Eta method exemplified by the Burgberg-Ort station
9.4 Application of the Eta method exemplified by the Burgberg-Ort
station
In the period from 23.03.1993 to 11.11.1999 approximately 130 discharge
measurements were taken at the Burgberg-Ort station. The stage was recorded
continuously from 01.03.1993 on.
The following steps are to be executed in order to apply the Eta method in your
special information system.
• creating the envelope curve (SKED)
• calculating the Eta time series
• calculating the Q time series
9.5 Creating the envelope curve
The varying flume hydraulics is considered for Burgberg-Ort by 12 rating curves in total
(Harp method). To replace the Harp method by the Eta method, the two outer rating
curves are used as Qo and Qz of the envelope curve we want to create. The created
envelope curve is valid from 01.01.1950 on.
To create the envelope curves, proceed as follows:
• Select in the Explorer of your special information system the editing mode Rating
curves.
• Choose the desired station and select the Q parameter.
The right window possibly displays now a list of existing rating curves.
• Choose in the context menu of the right window the function Wizard.
The SKED Wizard is started and helps you with the envelope curve creation.
• Choose in the wizard the top option (Create new rating curve or new version).
Now the envelope curve is created using a wizard.
• Choose the option Create rating curve.
• The second step is to set the status to preliminary and to enter a name for the
envelope curve. Accept the standard proposals for source parameter and units.
Remarks are optional.
• In the third step you may enter a curve validity, if it is already known to you.
• Activate the check box anyway to create a new version and activate <Next> to
continue.
SKED
321