20260323
11585700
1.0
FALSE
Median_DV_Urban_BLE
002
-
-
Geographic
GCS_WGS_1984
Angular Unit: Degree (0.017453)
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20260223
16060000
20260223
16060000
150000000
5000
dataset
20260223
File Geodatabase Table
Esri ArcGIS 13.3.0.52636
Median_DV_Urban_BLE
This table includes the Median DV values for the index and the 500-Year polygons.
<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN STYLE="text-decoration:underline;">FFRA_Grid</SPAN><SPAN>: This is a foreign key that relates to the Unique_ID field in the FFRA_Grid table. </SPAN></P><P><SPAN STYLE="text-decoration:underline;">med DV class_Urban_BLE</SPAN><SPAN>: Indicates the median flood severity category calculated for buildings within the 500-year floodplain, using the maximum depth-velocity product from available BLE models. This data is only available within Bexar, Travis, and Williamson counties, where the flood severity category may range from 0 to 5, where 5 represents extreme flood severity. Outside of these counties, pixels will have the default value of NULL.</SPAN></P></DIV></DIV></DIV>
This data was generated by AtkinsRéalis, using the Exposed Building Data and Flood Quilt (2024) provided by Texas Water Development Board (TWDB) Regional Flood Planning Group (RFPG). The Median DV Category was developed by WERC, using the Base Level Engineering (BLE) models, the FEMA Flood Severity Categories, TWDB RFPG Exposed Building Data, and the TWDB RFPG Flood Quilt (2024).
median dv category
depth
velocity
flood severity
flood
<DIV STYLE="text-align:Left;"><P STYLE="font-size:16ptmargin:0 0 11 0;"><SPAN>The FFRA is provided for the 30-county area at a spatial resolution of 1-kilometer by 1-kilometer for better computational efficiency as well as to align with input data with the coarsest resolution among those that were used in this study. In addition, the selection of the 1-kilometer by 1-kilometer pixel grid for processing FFRA can avoid confusion about the intent of the product – a finer resolution may give a false impression about the precision or intent of this study. This study is not intended to site sirens as part of outdoor warning siren systems but to identify flash flood-prone areas that warrant sirens. FFRA with a resolution of 1x1 kilometer can adequately serve as foundational information for identifying flash flood-prone areas that warrant sirens given the audible radius for outdoor warning sirens typically ranging from approximately 1 to 2 miles.</SPAN></P></DIV>
0
EPSG
6.2(3.0.1)
Median_DV_Urban_BLE
Table
83551
OBJECTID
OBJECTID
OID
4
0
0
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
FFRA_Grid
FFRA_Grid
String
100
0
0
med_DV_class_Urban_BLE
med_DV_class_Urban_BLE
Single
4
0
0