Land Use data can be edited on either the Land Use
Grid Window of the
Subcatchments Grid or the Land Use
Property Sheet.
Most data can be edited on the grid, but some fields cannot be displayed in the grid format.
To view and edit all Land Use data, use the Property Sheet.
This table describes all the data fields used to define a Land Use.
Fields that are common to the majority of objects can be found in the
Common Fields topic.
Land Use Data
Database Table Name:
sw_land_use
|
Field Name
|
Help Text
|
Database Field
|
Data Type
|
Size
|
Units
|
Precision
|
Default
|
Error Lower Limit
|
Error Upper Limit
|
Warning Lower Limit
|
Warning Upper Limit
|
|---|
|
Land use ID
|
The unique name that is used to identify this land use.
|
id
|
Text
|
254
|
|
0
|
|
|
|
|
|
| Washoff
|
The rate at which pollutants are washed off during rain events. The rates are entered on a Washoff grid which is displayed by clicking on the
 button.
Database Table Name:
sw_land_use_wo
|
Field Name
|
Help Text
|
Database Field
|
Data Type
|
Size
|
Units
|
Precision
|
Default
|
Error Lower Limit
|
Error Upper Limit
|
Warning Lower Limit
|
Warning Upper Limit
|
|---|
| Pollutant
|
The name of the pollutant.
A name of a new pollutant can be typed in or an existing one can be selected from a list of
defined pollutants.
|
pollutant
|
Text
|
254
|
|
|
|
|
|
|
|
| Washoff type
|
The type of SWMM washoff function which is to apply to this pollutant can be selected from a list. The options are:
See the
Build-up/Washoff Models topic for further information.
|
washoff_type
|
Text
|
16
|
|
|
|
|
|
|
|
| Exponential washoff coefficient
|
The runoff coefficient (in (mm/h)-C2/h) used in the EXP (Exponential) washoff type.
|
exponential_washoff_coeff
|
Double
|
|
|
|
|
0
|
|
|
|
| Rating washoff coefficient
|
The runoff coefficient used in the RC (Rating Curve) washoff type.
This is specified in (m3/s)-C2mg/s or (m3/s)-C2/s, depending on the pollutant.
|
rating_washoff_coeff
|
Double
|
|
|
|
|
0
|
|
|
|
| EMC washoff coefficient
|
The event mean concentration runoff coefficient used in the EMC (Event mean concentration) washoff type.
This is specified in mg/m3 or 1/m3, depending on the pollutant.
|
emc_washoff_coeff
|
Double
|
|
|
|
0
|
0
|
|
|
|
| Washoff exponent
|
The washoff exponent used in the EXP (Exponential) and RC (Rating Curve) washoff types.
|
exponential_washoff_exponent
|
Double
|
|
|
|
0
|
0
|
|
|
|
| Cleaning efficiency
|
The street cleaning removal efficiency (percent) for the determinant.
|
sweep_removal
|
Double
|
|
|
|
0
|
0
|
100
|
|
|
| BMP removal efficiency
|
Removal efficiency (percent) associated with any Best Management Practice (BMP) that may have been implemented.
|
bmp_removal
|
Double
|
|
|
|
0
|
0
|
100
|
|
|
|
washoff
|
Structure
|
|
|
|
|
|
|
|
|
| Build-up
|
The rate at which pollutants build up between rain events. The rates are entered on a
Build-up grid which is displayed by clicking on the
button.
Database Table Name:
sw_land_use_bu
|
Field Name
|
Help Text
|
Database Field
|
Data Type
|
Size
|
Units
|
Precision
|
Default
|
Error Lower Limit
|
Error Upper Limit
|
Warning Lower Limit
|
Warning Upper Limit
|
|---|
| Pollutant
|
The name of the pollutant.
A name of a new pollutant can be typed in or an existing one can be selected from a list of
defined pollutants.
|
pollutant
|
Text
|
254
|
|
|
|
|
|
|
|
| Build up type
|
The type of SWMM build up function which is to apply to this pollutant can be selected from a list. The options are:
- POW (Power)
- EXP (Exponential)
- SAT (Saturation)
- None
See the
Build-up/Washoff Models topic for further information.
|
build_up_type
|
Text
|
4
|
|
|
|
|
|
|
|
| Max. build-up
|
The maximum possible build up.
|
max_build_up
|
Double
|
|
|
|
|
0
|
|
|
|
| Power rate constant
|
The constant rate which is used by a POW (Power) build up type.
|
power_rate_constant
|
Double
|
|
SB
|
|
|
0
|
|
|
|
| Power time exponent
|
The time exponent which is used by a POW (Power) build up type.
|
power_time_exponent
|
Double
|
|
|
|
|
0
|
|
|
|
| Exponential rate constant
|
The constant rate which is used by a EXP (Exponential) build up type.
|
exp_rate_constant
|
Double
|
|
DR
|
|
|
0
|
|
|
|
| Half saturation constant
|
The number of days to reach half of the maximum buildup, which is used by the SAT (Saturation) build up type.
|
saturation_constant
|
Double
|
|
TD
|
|
|
0
|
|
|
|
| Unit
|
The type of unit which determines how build up is applied. The options are:
Area - Per unit area
Curb length - Per length of curb
|
unit
|
Text
|
16
|
|
|
Area
|
|
|
|
|
|
build_up
|
Structure
|
|
|
|
|
|
|
|
|
| Sweep interval
|
The number of days between street sweeping. Street sweeping may reduce the amount of available built-up sediment during a simulation.
|
sweep_interval
|
Double
|
|
TD
|
|
0
|
0
|
|
|
|
| Sweep availability
|
The fraction of pollutant buildup/washoff available for removal by street sweeping. The maximum is 1.
|
sweep_removal
|
Double
|
|
TD
|
|
0
|
0
|
|
|
|
| Last swept
|
The number of days since the last sweep (surface removal of sediment) at the start of the event.
|
last_sweep
|
Double
|
|
TD
|
|
0
|
0
|
|
|
|
