BRAT stores input, intermediate and output data in a GeoPackage. The two main database tables in this GeoPackage are the Reaches and ReachAttributes. The polyline geometry for each reach is stored in the Reaches table. This “feature class” is then related to the ReachAttributes table that contains the numerous attributes for each feature needed to run BRAT.
Each column in the ReachAttributes table is described below. Columns are grouped into two categories depending on which model phase they are populated; input and intermediate attributes that are calculated once during the BRAT Build phase of running the tool, and output attributes that are calculated each time that the BRAT Run phase of the model is run.
ReachID
| Data Type |
Integer |
| Units |
Auto-incrementing ID |
| Description |
Automatically asigned unique identifier of each reach. This is the primary key (FID, OID) for each feature. |
WatershedID
| Data Type |
Text |
| Units |
NA |
| Description |
Identifies which watershed the reach belongs to. This value references the Watersheds table. For North American BRAT runs this typically represents the HUC8 identifier. |
Geometry
| Data Type |
Binary |
| Units |
NA |
| Description |
The Reach polyline Geometry. |
ReachCode
| Data Type |
Integer |
| Units |
NA |
| Description |
Identifies the type of reach. This column references the ReachCodes defined in the ReachCodes table. For North American runs this is typically the NHD FCode. |
IsPeren
| Data Type |
Integer |
| Units |
Boolean |
| Description |
Depicts whether the reach is perennial or not. A value of zero means that the reach is NOT perennial. Any other value means that the reach is perennial. This column cannot be NULL. |
IsMainCh
| Data Type |
Ingeger |
| Units |
Boolean |
| Description |
Indicates whether the channel is the mainstem or not. Zero indicates that the reach is a side channel, diversion or other anabranch. Any other value indicates that the channel is the mainstem. |
IsMultiCh
| Data Type |
Integer |
| Units |
Boolean |
| Description |
Indicates whether the reach polyline represents a multi-threaded channel or not. Zero indicates that the reach is single threaded. Any other value indicates that the feature represents a multi-threaded channel. |
StreamName
| Data Type |
Text |
| Units |
NA |
| Description |
Optional stream name. For North American BRAT runs this typically represents the GNIS feature name. |
iGeo_Slope
| Data Type |
Float |
| Units |
Percent |
| Description |
Slope of the reach flow line. When BRAT calculates this value is samples the DEM at both ends of the reach polyline using a 30m buffer. The average elevation in each circle is subtracted and the difference divided by the length of the reach polyline. |
iGeo_ElMax
| Data Type |
Float |
| Units |
Meters |
| Description |
The higher elevation of either end of the reach polyline. When BRAT calculates this value it samples the DEM at both ends of the reach polyline using a 30m buffer. The higher of the two averages is then used as the max elevation. |
iGeo_ElMin
| Data Type |
Float |
| Units |
Meters |
| Description |
The lower elevation of either end of the reach polyline. When BRAT calculates this value it samples the DEM at both ends of the reach polyline using a 30m buffer. The lower of the two averages is then used as the max elevation. |
iGeo_Len
| Data Type |
Float |
| Units |
Meters |
| Description |
Length of the reach flow line polyline. When BRAT calculates this attribute is measures the actual, sinuous length along the polyline. |
Orig_DA
| Data Type |
Float |
| Units |
Square kilometers. |
| Description |
The total upstream drainage of the area that flows into the reach. This column differs from iGeo_DA because this value is never changed from the original data. It is provided as a means of comparing where users have overidden the original drainage area values. For North American BRAT runs this value is populated from the NHDPlus HR totDASqKm VAA attribute. |
iGeo_DA
| Data Type |
Float |
| Units |
Square Kilometers |
| Description |
This is the actual upstream drainage area used by BRAT when calculating the hydrology for a reach. This is initiated as a copy of the Orig_DA attribute value, but can be overridden should that value be deemed inaccurate. |
AgencyID
| Data Type |
Integer |
| Units |
NA |
| Description |
Identifies the land ownership for the property underlying the reach. This is calculated by intersecting the feature polyline with the land ownership layer and determining the agency that possessess the greatest length of reach. The ID is a lookup on the Agencies database table. |
Output Attributes
iVeg100EX
| Data Type |
Real |
| Units |
Beaver dams per kilometer |
| Description |
Existing beaver dam capacity based solely on vegetation located within 100m of the stream. |
iVeg_30EX
| Data Type |
Real |
| Units |
Beaver dams per kilometer |
| Description |
Existing beaver dam capacity based solely on vegetation located within 30m of the stream. |
iVeg100HPE
| Data Type |
Real |
| Units |
Beaver dams per kilometer |
| Description |
Historic beaver dam capacity based solely on vegetation located within 100m of the stream. |
iVeg_30HPE
| Data Type |
Real |
| Units |
Beaver dams per kilometer |
| Description |
Historic beaver dam capacity based solely on vegetation located within 100m of the stream. |
iPC_Road
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_RoadX
iPC_RoadVB
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_Rail
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_RailVB
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_LU
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_VLowLU
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_LowLU
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_ModLU
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_HighLU
| Data Type |
Real |
| Units |
|
| Description |
|
iHyd_QLow
| Data Type |
Real |
| Units |
Cubic feet per second (CFS) |
| Description |
Base streamflow that is execeeded 90% of the time. Low flow conditions are used in BRAT to determine if there is emough streamflow to support ponding behind beaver dams. |
iHyd_Q2
| Data Type |
Real |
| Units |
Cubic feet per second (CFS) |
| Description |
High streamflow that reccurs every two years. This flood discharge is used to calculate when high flows will cause dam blowouts. |
iHyd_SPLow
| Data Type |
Real |
| Units |
|
| Description |
Base stream power is caculated by converting the base streamflow (iHyd_QLow) into stream power using the discharge by the slope and the gravitational constant. |
iHyd_SP2
| Data Type |
Real |
| Units |
|
| Description |
High flow stream power is caculated by converting the base streamflow (iHyd_Q2) into stream power using the discharge by the slope and the gravitational constant. |
oVC_HPE
| Data Type |
Real |
| Units |
|
| Description |
|
oVC_EX
| Data Type |
Real |
| Units |
|
| Description |
|
oCC_HPE
| Data Type |
Real |
| Units |
|
| Description |
|
mCC_HPE_CT
| Data Type |
Real |
| Units |
Beaver Dam Count |
| Description |
The historic number of beaver dams that the reach could support. This is calculaterd by multiplying the historic beaver dam capacity (oHPE_EX) by the length of the channel (iGeo_Len). |
oCC_EX
| Data Type |
Real |
| Units |
Beaver Dams Per Kilometer |
| Description |
Existing Beaver Dam Capacity. This is the main output of the beaver dam fuzzy inference system. |
mCC_EX_CT
| Data Type |
Real |
| Units |
Beaver Dam Count |
| Description |
|
LimitationID
| Data Type |
Integer |
| Units |
NA |
| Description |
The primary limitations to beaver dams occurring on the reach. This is a lookup to the Limitations table in the BRAT database. |
RiskID
| Data Type |
Integer |
| Units |
NA |
| Description |
The primary risk to beaver dams occurring on the reach. This is a lookup to the Risk table in the BRAT database. |
OpportunityID
| Data Type |
Integer |
| Units |
NA |
| Description |
The types of opportunities for beaver dams occurring on the reach. This is a lookup to the Opportunities table in the BRAT database. |
ManagementID
| Data Type |
Integer |
| Units |
|
| Description |
|
iPC_Canal
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_DivPts
| Data Type |
Real |
| Units |
|
| Description |
|
iPC_Privat
| Data Type |
Real |
| Units |
|
| Description |
|
oPC_Dist
| Data Type |
Real |
| Units |
|
| Description |
|
mCC_HisDep
| Data Type |
Real |
| Units |
|
| Description |
|