Coastal Hazard Bulletin

Issue No. 6

The purpose of the Coastal Hazard Mailing List is to provide up-to-date coastal flood hazard information pertinent to the Federal Emergency Management Agency and the National Flood Insurance Program. Subscribers will receive new mailings on a monthly basis.

CHAMP Survey

Prior to commencing the Wave Height Analysis Program exercise, your assistance is requested to complete a survey of CHAMP (the program) and the Coastal Hazard mailing list.

  1. Do you use the Coastal Hazard mailing list? What recommendations could you offer?
  2. Do you use CHAMP for your coastal flood hazard modeling needs?
  3. What improvements to CHAMP could you offer? Would the addition of a mapping feature (import/export of digital/GIS data) improve the applicability of CHAMP?

CHAMP Program 4 - Wave Height Analysis

Introduction
Attached please find the file Complete.mdb and the folder Complete.zip (both files saved in ch_oct01.zip which can be downloaded, in Winzip format, by clicking here) which include a completed CHAMP database and transect data files. This database can be used to check your solutions for the Erosion Treatment program completed in the September 2001 Bulletin, as well as guide you through the remainder of developing your CHAMP database associated with this mailing list. Extract the files in Complete.zip and save in a folder named Complete. Save the folder and the Complete.mdb file to your local directory (C:\Program Files\Champ). The Complete.mdb database can be opened by clicking on the Open button on the CHAMP main menu button bar.

Detailed instructions for operating the Wave Height Analysis Program are provided on pp. 28-35 of the CHAMP User's Manual.

Start Program
Click on the WHAFIS button on the main menu button bar to begin the Wave Height Analysis program.

Populate Data
Click the Populate Data item under the File menu for each transect to extract data from the Erosion Treatment program. The station and elevation columns in this window will be filled in with the transect data. WHAFIS only uses the points from the zero elevation shoreward.

1% Annual Chance Stillwater Elevation (100-year SWEL)
The Total 100-yr SWEL column of the WHAFIS Program Data table window will be populated with the Total SWEL (Stillwater plus wave setup) as entered in the General Transect Description & Parameter program. The SWEL for Transect 1 remains unchanged throughout the length of the transect and therefore does not need to be adjusted.

WHAFIS Card Selection
The WHAFIS Card column will be defaulted to the IF card except for the first card. The first input card to WHAFIS must always be an IE card. By clicking on a field for each station, a drop-down menu will appear with all the card options for WHAFIS. Click on the appropriate card for each station.

For Transect 1 of your CHAMP Complete' database, while the initial WHAFIS card should remain an IE (Initial Elevation) card, the next three cards should be changed to OF (Overwater Fetch) cards. The three landwardmost cards should be changed to VH (Vegetation Header for Marsh Grass) cards by selecting VH on the drop-down menu. Select Mid Atlantic at the Primary Region field of the additional input window. Also select MG (Marsh Grass) from the bottom of that window where "saltmeadow grass" should be selected at the Plant Type field. In both the VH and MG card cases, the other fields in each window will automatically load.

Transect 2 Development
Similarly, but slightly more complicated, the WHAFIS Card and 100-year SWEL determination procedures should be followed for Transect 2. Transect 2 includes a change in the 100-year SWEL as the transect proceeds inland and crosses over a barrier island and into an inland bay or other secondary flooding source. Additional transect points are needed where the ground elevation rises above and then drops below the 100-year SWEL at the frontside and backside of the barrier island. Additional points can be added through the graphical display by clicking the insert button and then clicking on the required location along the profile. Two points should be added: (station-elevation pair [191, 13] at the frontside of the barrier island) where the Total SWEL is 13ft; and ([630,7] at the backside of the barrier island) where the SWEL is 7ft (as presented at the bottom of the General Transect Description & Parameter Program window). The SWEL should remain at 13ft until the backside of the barrier island where the SWEL should then be changed to 7ft. This 7ft SWEL should be extended to the landwardmost extent of the transect. As shown in your Complete database, in the landward direction, the WHAFIS cards should be IE (1st card); OF (2nd-4th cards); AS (5th card), which should extend from the 13ft elevation on the frontside of the barrier island to the 7ft elevation on the backside of the barrier island; and IF (6th-12th cards).

WHAFIS Computational Application
Click on the Run WHAFIS item under the Program menu of the WHAFIS Program Data table window to execute the WHAFIS program. A DOS-run window will open; it will appear either minimized or opened on screen. When "Stop - Program terminated" appears in the DOS window, the WHAFIS program is complete, and the DOS window can then be closed. If the WHAFIS program ran successfully, a "WHAFIS RUN finished" box will appear; click on the OK button. If WHAFIS did not run correctly, an error message will appear, and the input file should be checked for errors.

Graphic Display of WHAFIS Data
After developing the WHAFIS data table, click on the Graph button on the WHAFIS Program window to graphically plot the original, adjusted, and eroded ground elevation line, and the total 100-year SWEL (with wave setup if applicable). After running the WHAFIS model, click on the Graph Results item under the Graph menu while in the WHAFIS Program graphic window to see a graphical plot of the WHAFIS results. This will bring up a plot of the profile showing input profile, stillwater elevations, wave envelope and color-coded flood hazard zone bars. These bars will also be displayed in the Summary Graphics program.

Additional information on the graphic display of CHAMP-modeled results was introduced in the August 2001 Bulletin. Detailed instructions regarding graphical features of CHAMP will be presented in the December 2001 Bulletin and on pages 43-47 of the CHAMP User's Manual.

WHAFIS Data Viewing
Click on the Results drop-down menu to view the WHAFIS input and output text files, and WHAFIS program output results in tabular form.

Exiting WHAFIS Program
When finished with the WHAFIS Program, close the WHAFIS windows by clicking on the X in the upper right corner of each window. Then, continue with either Program 5 - Wave Runup Analysis or Program 6 - Summary Tables and Graphics for Mapping.

Helpful Hints for CHAMP Program 4

First, when inserting or removing points in the WHAFIS Program graphic window, the Refresh button on the WHAFIS Program main menu bar should be clicked to view the results of the inserted points. More importantly, the Update Table menu item under the Graph menu must be selected to update the WHAFIS Program data table window with points inserted or removed in the WHAFIS Program graphic window.

Second, in order to display graphics to their maximum extent, the user should adjust axes scales and intervals by selecting Setup under the Graph drop-down menu in the WHAFIS program graphic. After adjusting the graph, the Refresh button on the main menu bar should be selected to view the changes.

Preparation for the November 2001 Bulletin

In preparation for the November 2001 Bulletin, you should complete the exercise presented above. Next month, we will continue to develop your CHAMP database by working on Program 5 - Wave Runup Analysis.

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Last Modified: Wednesday, 20-Jun-2007 11:57:20 EDT