Each subcatchment in a network requires an associated Land Use definition. A Land Use can be associated with any number of subcatchments.
The Land Use allows the definition of up to 12 different Runoff Surfaces for the subcatchment. It also allows the definition of default values for population density, wastewater profile and infiltration profile, connectivity and runoff volume surfaces. These defaults can be overridden in the associated subcatchments.
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: hw_land_use
|
Field Name |
Description |
Database Field |
Size |
Precision |
Default |
Error Lower Limit |
Error Upper Limit |
Warning Lower Limit |
Warning Upper Limit |
||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Land Use ID |
A name used to identify this land use |
land_use_id |
Text |
64 |
|
0 |
|
|
|
|
|
|
Description |
A description of this Land Use. |
land_use_description |
Text |
80 |
|
0 |
|
|
|
|
|
|
Population Density |
The number of people per hectare. If you don't give a figure for population in the subcatchment data, ICMLive Operator Client uses this figure and the subcatchment contributing area to calculate a population. |
population_density |
Double |
|
PD |
1 |
|
0 |
|
|
|
|
Wastewater Profile |
The wastewater profile that applies to this land use. The wastewater profile contains dimensionless values that the software multiplies by the base wastewater flow to give a time varying aspect. This is the default for subcatchments of this land use, where you have not defined a specific profile in the subcatchment data |
wastewater_profile |
Long Integer |
|
|
0 |
|
0 |
999 |
|
|
|
Connectivity (%) |
The percentage of foul flow from this subcatchment that drains into the system you are modelling. Foul flow is derived from population, per capita flow and multiplier profile. The valid range for this field is 0 - 100. This is the default for subcatchments of this land use, where you have not defined a value for connectivity in the subcatchment data |
connectivity |
Long Integer |
|
|
0 |
|
0 |
100 |
|
|
|
Pollution Index |
The ID of the Pollution Index associated with this land use. The Pollution Index defines the washoff characteristics for any subcatchment that uses this land use |
pollution_index |
Long Integer |
|
|
0 |
|
1 |
99 |
|
|
|
Runoff Surface 1 |
The reference for the runoff surface definition can be selected from the dropdown. These define the runoff surfaces for subcatchments that use this land use. You can define the parameters for a runoff surface on the Runoff Surface Grid Window in the Subcatchments Grid. |
runoff_index_1 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 1 (%) |
A default percentage area for the runoff surface. For example, if you enter 50% for surface 10, 50% of each subcatchment area will be of this surface type, by default. However, any local areas entered for individual subcatchments will override this default. |
p_area_1 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 2 |
see Runoff Surface 1 |
runoff_index_2 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 2 (%) |
see Default Area 1 |
p_area_2 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 3 |
see Runoff Surface 1 |
runoff_index_3 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 3 (%) |
see Default Area 1 |
p_area_3 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 4 |
see Runoff Surface 1 |
runoff_index_4 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 4 (%) |
see Default Area 1 |
p_area_4 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 5 |
see Runoff Surface 1 |
runoff_index_5 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 5 (%) |
see Default Area 1 |
p_area_5 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 6 |
see Runoff Surface 1 |
runoff_index_6 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 6 (%) |
see Default Area 1 |
p_area_6 |
Double |
|
|
0 |
|
0 |
100 |
|
|
|
Runoff Surface 7 |
see Runoff Surface 1 |
runoff_index_7 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 7 (%) |
see Default Area 1 |
p_area_7 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 8 |
see Runoff Surface 1 |
runoff_index_8 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 8 (%) |
see Default Area 1 |
p_area_8 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 9 |
see Runoff Surface 1 |
runoff_index_9 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 9 (%) |
see Default Area 1 |
p_area_9 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 10 |
see Runoff Surface 1 |
runoff_index_10 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 10 (%) |
see Default Area 1 |
p_area_10 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 11 |
see Runoff Surface 1 |
runoff_index_11 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 11 (%) |
see Default Area 1 |
p_area_11 |
Double |
|
|
3 |
|
0 |
100 |
|
|
|
Runoff Surface 12 |
see Runoff Surface 1 |
runoff_index_12 |
Long Integer |
|
|
0 |
|
1 |
99999 |
|
|
|
Default Area 12 (%) |
see Default Area 1 |
p_area_12 |
Double |
|
|
3 |
|
0 |
100 |
|
|