Task A2/B3: Preparing Basin and Stream Shapefiles for Localization

Updated 03/06/08

This process creates the final basin and stream shapefiles to be used with FFMP Advanced. The basin shapefile must be processed to ensure that all basins are larger than a specified minimum area (1.74 square miles). Removing the very small basins is required to minimize FFMP CPU usage and to ensure all basins can be resolved on the D2D display. In addition, the basin and stream shapefiles must be checked to make sure the required attributes exist and are in the expected order in the attribute table.

Step 1 - Aggregate Small Basins (Automated)

Procedure:

  1. Make the basin theme active by clicking on its legend.
  2. From the Bsn-Tools menu, select Merge By Area.
    1. Enter 1.74 for the minimum area threshold in square miles .
    2. Name the new file wsarea.shp.

Step 2 - Aggregate Remaining Small Basins (Semi-Automated)

Procedure:

  1. Make wsarea the active theme.
  2. Check for basins that are smaller than the specified area threshold (these will often be outlet basins):
    1. Click the Open Theme Table button to open the attribute table for the basin theme.
    2. Click the Query button.
    3. Build the following query string: ([Area_sq_mi] < 1.74)
    4. Click the New Set button.
    5. Close the Query window.
  3. If there are any basins selected after the query, you should examine each one and determine if further aggregation is needed. It is helpful to overlay the derivedstr_all shapefile to help determine which basins should be aggregated. Most basins can be aggregated with an upstream or downstream basin. Select the basin that is smaller than 1.74 square miles and the basin with which to aggregate it. Use Merge Basins under the Bsn-Tools menu to aggregate them.  If you need to use Merge Basins, name the new shapefile wsarea2.shp.

Step 3 - Check Basin Shapefile Attributes

Procedure:

  1. Make the wsarea2 (or wsarea if you did not do any additional aggregation in Step 2) theme active by clicking on its legend.
  2. Click the Open Theme Table button to open the attribute table for the wsarea2 theme.
  3. From the Table menu, select Properties.
  4. You will likely have the following fields in your attribute table (not necessarily in this order):
    1. Shape
    2. Pfaf_id
    3. Streamname
    4. Huc
    5. Huc_name
    6. X_outlet
    7. Y_outlet
    8. State
    9. Cwa
    10. Countyname
    11. Fips
    12. Rfc
    13. Modified
    14. Reservoir
    15. X_centroid
    16. Y_centroid
    17. Pfaf_aggr
    18. Basin_id
    19. Parent_id
    20. Length_mi
    21. Area_sq_mi
    22. Flow_acc
    23. Upstream1
    24. Upstream2
    25. Upstream3
    26. Upstream4, etc.
    27. Merged

    Specific items to check: Please make sure there is a Modified field (#13 above). This is one of the fields required by FFMP. If the [Modified] field does not exist, it must be created:

    1. From the Table menu, select Start Editing.
    2. From the Edit menu, select Add Field.
    3. In the Field Definition box that appears, enter Modified for the name, Number for the type, 1 for the width, and 0 for decimal places. Click OK.
    4. From the Table menu, select Stop Editing and save the edits.

    Also, if there are too many additional fields in the attribute table (for example, numerous [Upstream] fields), localization problems may occur. If you have more than 30 attribute fields, please contact Ami Arthur (Ami.Arthur@noaa.gov or 405-325-6457) for assistance.

    *PLEASE REARRANGE THE FIELDS TO MATCH THE ABOVE ORDER.*

  5. Return to the view.
  6. Make sure the wsarea2 theme is the only active theme.
  7. Click the Clear Selection button to clear any selection on the theme.
  8. From the Theme menu, select Convert to Shapefile.
  9. Enter FFMP_aggr_basins.shp for the new name.

Step 4 - Check Stream Shapefile Attributes

Procedure:

  1. Make the derivedstr_all theme active by clicking on its legend.
  2. Click the Open Theme Table button to open the attribute table for the derivedstr_all theme.
  3. From the Table menu, select Properties.
  4. You will likely have the following fields in your attribute table (not necessarily in this order):
    1. Shape
    2. Pfaf_id
    3. Streamname
    4. Huc
    5. Huc_name
    6. X_outlet
    7. Y_outlet
    8. State
    9. Cwa
    10. Countyname
    11. Fips
    12. Rfc
    13. Reservoir
    14. X_centroid
    15. Y_centroid
    16. Pfaf_aggr
    17. Basin_id
    18. Parent_id
    19. Length_mi
    20. Area_sq_mi
    21. Flow_acc
    22. Upstream1
    23. Upstream2
    24. Upstream3
    25. Upstream4 (possibly)

    Specific items to check: Please make sure there is NOT a Modified field.

    *PLEASE REARRANGE THE FIELDS TO MATCH THE ABOVE ORDER.*

  5. Return to the view.
  6. Make derivedstr_all the active theme.
  7. Click the Clear Selection button to clear any selection on the theme.
  8. From the Theme menu, select Convert to Shapefile.
  9. Enter FFMP_ref_sl.shp for the new name.

Step 5 - Copy and Gzip the Files

You should now have the following final files:

NOTE: The *.shp files must be gzipped:

The above files (*.dbf, *.shp.gz, and *.shx) should be copied to AWIPS into /data/local. Do not remove the old FFMP shapefiles from AWIPS yet.

NOTE: When you receive OB8.3, you will need to move the new files from /data/local to /data/fxa/nationalData prior to localization.

Step 6 - Notification of Tier I Completion

Please send an e-mail to Ami.Arthur@noaa.gov and cc the appropriate regional contact(s) (see below) when you have completed the Tier I processing. Please indicate 1) whether you processed the files using ArcMap 9.2 or ArcView 3.x, and 2) approximately how long it took to complete Tier I.

Regional Contacts

Central Region: Noreen.Schwein@noaa.gov and also please use the EMRS to report completion.

Eastern Region: George.McKillop@noaa.gov

Southern Region: Diane.Cooper@noaa.gov and Eric.Howieson@noaa.gov

Western Region: Please use the EMRS to report completion.