FFMPA Shapefile Instructions for ArcView 3.x

Updated 02/20/08

Please contact Ami Arthur if you have questions or need assistance with this procedure (Ami.Arthur@noaa.gov or 405-325-6457).

Downloading the Basin Customization Extension and CWA Shapefile

If you are using ArcView 3.x, please download the new version of the Basin Customization Extension and save it in your extensions directory. For Windows systems, the extensions directory should be *\ESRI\Av_gis30\ArcView\Ext32 and for UNIX/Linux systems you can save the file in your home directory. You can also access the extension documentation (maintained by Paul Jendrowski, WFO RNK) for reference.

If you do not already have a CWA shapefile in geographic coordinates, please download it from http://www.weather.gov/geodata/catalog/wsom/html/cwa.htm.

Getting Started in ArcView 3.x

Start ArcView 3.x. From the File menu, select Extensions. Scroll down to AMBER Basin Customization. You may have multiple extensions with this name in your list. Click the *name* of each one (not the checkbox) to see the version information in the "About" box. Click here to see the extension version that was just downloaded. In the list of extensions in ArcView, click the checkbox next to this version and uncheck any other AMBER Basin Customization extensions that are already checked. Click OK.

Open a new View. From the View menu, select Properties. Set the Map Units to decimal degrees and the Distance Units to miles. Click OK.

From the File menu, select Set Working Directory and enter the directory where you want the processed files to be created. From the File menu, select Save Project and select a name for your project file.

Merging the Downloaded Regional Basin Shapefiles

Add the basinsXXXXX_poly and derivedstr_line shapefiles to the View. If you have more than one basinsXXXXX_poly shapefile covering your area, they must be merged into one shapefile. Use the shift key to select all of the basinsXXXXX_poly shapefiles. From the Bsn-Tools menu, select Merge Active Themes. Enter a name for the merged basin file (we will call it basinsmrg_poly here). It may take a while for this step to process (possibly over an hour).

Extracting Basins/Streams by Buffered CWAs

Buffering the CWAs

Add the CWA shapefile to the View. Use the Select Features tool to select your CWA and the CWAs for which you have flash flood backup responsibility (use the Shift-key to select multiple polygons). (Note: You can also make these selections by opening the attribute table and selecting the appropriate records.)

Make sure the CWA shapefile is the active theme. From the Theme menu, select Create Buffers. Enter the following as you step through the Buffer Wizard:

1) What do you want to buffer?
The features of a theme (CWA shapefile)
(Make sure "Use only the selected features" is selected.)

Click Next.

2a) How do you want to create buffers?
At a specified distance (15)
2b) Distance Units are:

Click Next.

3a) Dissolve barriers between buffers?
3b) Create buffers so they are:
Only outside the polygon(s)
3c) Where do you want the buffers to be saved?
In a new theme (allcwa_buff.shp)

Click Finish.

The allcwa_buff.shp theme will be added to the View.

Extracting Features

Make basinsmrg_poly the active theme. From the Theme menu, choose Select by Theme. Enter the following:

Select the features of active themes that:
the selected features of:

Click New Set. Display the basinsmrg_poly.shp theme to make sure the correct features were selected.

Make sure basinsmrg_poly is the active theme. From the Theme menu, select Convert to Shapefile. Name the new theme basins_all.shp.

Repeat the "Extracting Features" procedure above using the derivedstr_line theme. The basins extracted from derivedstr_line should be converted to a new shapefile named derivedstr_all.shp.

Updating the Hydrologic-Connectivity Attributes

Make basins_all.shp the active theme. From the Bsn-Tools menu, select Update Links in NBR Shapefiles. When it has completed, you should see the message "Upstream/downstream links have been updated. Please run Validate Links to verify." Click OK to close the window.

From the Bsn-Tools menu, select Validate Basins.

Repeat the above steps to update the hydrologic-connectivity attributes in derivedstr_all.shp.

If you do not receive any errors from the Validate Basins tool, you may proceed to one of the two options below.

There are two options for proceeding with shapefile dataset processing for FFMPA. Please choose the option that best suites your needs and follow the link to continue with the instructions.

Option A: Complete FFMP Shapefile Replacement

This option is the easiest to implement. You will simply use the basin and stream shapefiles that were downloaded and prepare them for AWIPS localization. This option should be chosen if:

a) you have not done any customization to your previous FFMP shapefiles that you would like to preserve,


b) you have only made stream name modifications in your previous FFMP shapefiles and would like to transfer those to the newly downloaded shapefiles. PLEASE NOTE: If you modified stream names in the aggregated version of the previous FFMP shapefiles, there will not be a one-to-one transfer to the new FFMP shapefiles (which are in the native, unaggregated format). This is because there is not a one-to-one relationship between the basins that have been aggregated and the native basins. Past transfers of stream names from aggregated to native basins indicate that about 15% of the transferred names require post-transfer checking to make sure the transferred name is the desired name for that basin (the names that should be checked will be flagged during the transfer procedure).

Proceed to Option A Instructions

Option B: Integration of Downloaded FFMP Shapefiles with Previous FFMP Shapefiles

This option should be used if you have done any customization (other than modification of stream/basin names) to your previous FFMP shapefiles that you would like to preserve. The basic approach is to first select the customized areas in your previous FFMP shapefiles, then select the areas surrounding these in the downloaded FFMP shapefiles and merge them together.

This option is complicated, and a reasonable level of familiarity with GIS and the FFMP basin/stream dataset is required for anyone who chooses this route. Please contact Ami Arthur before beginning this option to discuss your specific case (Ami.Arthur@noaa.gov or 405-325-6457).

Proceed to Option B Instructions

NSSL Home :: Basin Delineation Home :: FFMPA Datasets