Surface Definition for Surface Polygons
The surface definition alternative editor for surface polygons is used to create various data sets for the surface characteristics of surface polygons. Surface polygons include buildings, land use areas, adjustment areas, road areas and void areas. The following columns are available:
| Column | Description |
|---|---|
| ID | Displays the unique identifier for each element in the alternative. |
| Label | Displays the label for each element in the alternative. |
| SCS CN Adjustment Type | Select how a value for CN will be assigned to this area. |
| SCS CN (User Defined) | Specify the SCS Curve Number for the area. |
| Impermeability Fraction Adjustment Type | Select how a value for Impermeability Fraction will be assigned to this area. |
| Impermeability Fraction (User Defined) | The Impermeability Fraction value for this area. |
| Manning’s n Adjustment Type | Select how a value for Manning’s will be assigned to this area. |
| Manning’s n (User Defined) | The Manning’s n value for this area. |
| Rational C Adjustment Type | Select how a value for Rational coefficient will be assigned to this area. This corresponds to Rational C term for the Rational Method, and the Rational Volumetric Coefficient (Cv) term for the Modified Rational (UK) Method. |
| Rational C (User Defined) | Specify the Rational coefficient for the area. This corresponds to Rational C term for the Rational Method, and the Rational Volumetric Coefficient (Cv) term for the Modified Rational (UK) Method. |
| Land Cover Type | The referenced surface land use catalog to use for this surface polygon. |
| Type | Select the element type for the 2D modeling area. |
| Elevation Adjustment Operation | The type of adjustment to make to elevations. |
| Elevation Adjustment | Elevation adjustment value to be applied to the underlying grid. |
| Priority |
When two grid adjustment areas overlap, the precedence is determined by priority. |