Accessing the New Storm Events Scenario Wizard

You access the new storm events scenario wizard through the scenario manager. Open the scenario manager (see Opening Managers ); click the New button and then click the New Storm Event Scenarios menu item.

New Storm Events Scenarios Wizard

The storm events wizard assists in streamlining the process of creating scenarios, alternatives, calculation options and storm events for a specific set of return periods and durations. The wizard will guide you through the process of entering the required data to generate these items.

The set of scenarios, alternatives, calculation options and storm events created are then used with the Critical Storm Analysis tool.

It is important to note that this wizard may generate a lot of scenarios, alternatives, calculations and storm events depending on the settings.

The wizard will create new scenarios, alternatives, calculation options and storm events. It will not modify any existing item. For additional alternative types not created, it will use the first base scenario of that type as the default assignment.

Storm Event Profiles

This wizard will require the use of storm event profiles. A storm event profile is a dimensionless rainfall curve that can be used to create a time-depth or time-intensity storm event. A storm event profile can either be a fixed-time dimensionless curve or a true dimensionless curve.

The product ships with several storm event profiles that can be used.

These include the “UK Storm Profiles.xml” file which is used in the United Kingdom.

This profile library contains the dimensionless storm event profiles “50% Summer Profile” and “75% Winter Profile”. These are dimensionless rainfall curves.

Another storm event profile included is the “Australian Rainfall and Runoff 1987.xml” file which is used in Australia. This file will soon be superseded by the new “Australia Rainfall and Runoff 2016” data. For more information on the new Australian Rainfall and Runoff 2016 data, see HTTP://WWW.BOM.GOV.AU/WATER/DESIGNRAINFALLS/IFD/. You can import this new data in the storm data dialog and then use the IFD data in this wizard.

A fixed-time dimensionless curve uses a fixed start, increment end time with a dimensionless depth. The dimensionless depth is multiplied by the depth of the storm to create a depth at that point in time.

A dimensionless curve uses a dimensionless start, increment and end value along with a dimensionless depth. The dimensionless start, increment end values are multiplied by the duration of the storm event to calculate the time. The dimensionless depth is then multiplied by the depth of the storm event to calculate the depth at that time.