APPENDIX B - Visual Object Properties
B.1 Rain Gage Properties
| Name | User-assigned rain gage name. |
| X-Coordinate | Horizontal location of the rain gage on the Study Area Map. If left blank then the rain gage will not appear on the map. |
| Y-Coordinate | Vertical location of the rain gage on the Study Area Map. If left blank then the rain gage will not appear on the map. |
| Description | Optional description of the rain gage. |
| Tag | Optional label used to categorize or classify the rain gage. |
| Rain Format | Format in which the rain data are supplied:
INTENSITY: each rainfall value is an average rate in inches/hour (or mm/hour) over the recording interval, VOLUME: each rainfall value is the volume of rain that fell in the recording interval (in inches or millimeters), CUMULATIVE: each rainfall value represents the cumulative rainfall that has occurred since the start of the last series of non-zero values (in inches or millimeters). |
| Rain Interval | Time interval between gage readings in either decimal hours or hours:minutes format. |
| Snow Catch Factor | Factor that corrects gage readings for snowfall. |
| Data Source | Source of rainfall data; either TIMESERIES for user-supplied time series data or FILE for an external data file. |
| TIME SERIES | |
| - Series Name | Name of time series with rainfall data if Data Source selection was TIMESERIES; leave blank otherwise (double-click to edit the series). |
| DATA FILE | |
| - File Name | Name of external file containing rainfall data. |
| - Station No. | Recording gage station number. |
| - Rain Units | Depth units (IN or MM) for rainfall values in the file. |
B.2 Subcatchment Properties
| Name | User-assigned Subcatchment name. |
| X-Coordinate | Horizontal location of the Subcatchment's centroid on the Study Area Map. If left blank then the Subcatchment will not appear on the map. |
| Y-Coordinate | Vertical location of the Subcatchment's centroid on the Study Area Map. If left blank then the Subcatchment will not appear on the map. |
| Description | Optional description of the Subcatchment. |
| Tag | Optional label used to categorize or classify the Subcatchment. |
| Rain Gage | Name of the rain gage associated with the Subcatchment. |
| Outlet | Name of the node or Subcatchment which recieves the Subcatchment's runoff. |
| Area | Area of the Subcatchment (acres or hectares). |
| Width | Characteristic width of the overland flow path for sheet flow runoff (feet or meters). An initial estimate of the characteristic width is given by the Subcatchment area divided by the average maximum overland flow length. The maximum overland flow length is the length of the flow path from the inlet to the furthest drainage point of the Subcatchment. Maximum lengths from several different possible flow paths should be averaged. These paths should reflect slow flow, such as over pervious surfaces, more than rapid flow over pavement, for example. Adjustments should be made to the width parameter to produce good fits to measured runoff hydrographs. |
| % Slope | Average percent slope of the Subcatchment. |
| % Imperv | Percent of land area which is impervious. |
| N-Imperv | Manning’s n for overland flow over the impervious portion of the Subcatchment (see Section A.6 for typical values). |
| N-Perv | Manning’s n for overland flow over the pervious portion of the Subcatchment (see Section A.6 for typical values). |
| Dstore-Imperv | Depth of depression storage on the impervious portion of the Subcatchment (inches or millimeters) (see Section A.5 for typical values). |
| Dstore-Perv | Depth of depression storage on the pervious portion of the Subcatchment (inches or millimeters) (see Section A.5 for typical values). |
| % Zero-Imperv | Percent of the impervious area with no depression storage. |
| Subarea Routing | Choice of internal routing of runoff between pervious and impervious areas:
IMPERV: runoff from pervious area flows to impervious area, PERV: runoff from impervious area flows to pervious area, OUTLET: runoff from both areas flows directly to outlet. |
| Percent Routed | Percent of runoff routed between subareas. |
| Infiltration | Click on the  button to select and edit infiltration parameters for the Subcatchment. |
| Groundwater | Click on the button to select and edit groundwater flow parameters for the Subcatchment. |
| Snow Pack | Name of snow pack parameter set (if any) assigned to the Subcatchment. |
| Initial Buildup | Click on the button and select Initial Pollutant Buildup to specify initial quantities of pollutant buildup over the Subcatchment. |
| Land Uses | Click on the button and select Land Use Assignment to assign land uses to the Subcatchment. |
| Curb Length | Total length of curbs in the Subcatchment (any length units). Used only when pollutant buildup is normalized to curb length. |
B.3 Junction Properties
| Name | User-assigned junction name. |
| X-Coordinate | Horizontal location of the junction on the Study Area Map. If left blank then the junction will not appear on the map. |
| Y-Coordinate | Vertical location of the junction on the Study Area Map. If left blank then the junction will not appear on the map. |
| Description | Optional description of the junction. |
| Tag | Optional label used to categorize or classify the junction. |
| Inflows | Click on the button and select Inflow to assign time series, dry weather, or RDII inflows to the junction. |
| Treatment | Click on the button and select Treatment to edit a set of treatment functions for pollutants entering the node. |
| Invert El. | Invert elevation of the junction (feet or meters). |
| Max. Depth | Maximum depth of junction (i.e., from ground surface to invert) (feet or meters). |
| Initial Depth | Depth of water at the junction at the start of the simulation (feet or meters). |
| Surcharge Depth | Additional depth of water beyond the maximum depth that is allowed before the junction floods (feet or meters). This parameter can be used to simulate bolted manhole covers. |
| Ponded Area | Area occupied by ponded water atop the junction after flooding occurs (sq. feet or sq. meters). If the Allow Ponding Simulation Option is turned on, a non-zero value of this parameter will allow ponded water to be stored and subsequently returned to the conveyance system when capacity exists. |
B.4 Outfall Properties
| Name | User-assigned outfall name. |
| X-Coordinate | Horizontal location of the outfall on the Study Area Map. If left blank then the outfall will not appear on the map. |
| Y-Coordinate | Vertical location of the outfall on the Study Area Map. If left blank then the outfall will not appear on the map. |
| Description | Optional description of the outfall. |
| Tag | Optional label used to categorize or classify the outfall. |
| Inflows | Click on the button and select Inflow to assign time series, dry weather, or RDII inflows to the outfall. |
| Treatment | Click on the button and select Treatment to edit a set of treatment functions for pollutants entering the node. |
| Invert El. | Invert elevation of the outfall (feet or meters). |
| Tide Gate | YES - tide gate present which prevents backflow
NO - no tide gate present |
| Type | Type of outfall boundary condition:
FREE: outfall stage determined by minimum of critical flow depth and normal flow depth in the connecting conduit NORMAL: outfall stage based on normal flow depth in connecting conduit FIXED: outfall stage set to a fixed value TIDAL: outfall stage given by a table of tide elevation versus time of day TIMESERIES: outfall stage supplied from a time series of elevations. |
| Fixed Stage | Water elevation for a FIXED type of outfall (feet or meters). |
| Tidal Curve Name | Name of the Tidal Curve relating water elevation to hour of the day for a TIDAL outfall (double-click to edit the curve). |
| Time Series Name | Name of time series containing time history of outfall elevations for a TIMESERIES outfall (double-click to edit the series). |
B.5 Flow Divider Properties
| Name | User-assigned divider name. |
| X-Coordinate | Horizontal location of the divider on the Study Area Map. If left blank then the divider will not appear on the map. |
| Y-Coordinate | Vertical location of the divider on the Study Area Map. If left blank then the divider will not appear on the map. |
| Description | Optional description of the divider. |
| Tag | Optional label used to categorize or classify the divider. |
| Inflows | Click on the button and select Inflow to assign time series, dry weather, or RDII inflows to the divider. |
| Treatment | Click on the button and select Treatment to edit a set of treatment functions for pollutants entering the node. |
| Invert El. | Invert elevation of the divider (feet or meters). |
| Max. Depth | Maximum depth of divider (i.e., from ground surface to invert) (feet or meters). |
| Initial Depth | Depth of water at the divider at the start of the simulation (feet or meters). |
| Surcharge Depth | Additional depth of water beyond the maximum depth that is allowed before the junction floods (feet or meters). This parameter can be used to simulate bolted manhole covers. |
| Ponded Area | Area occupied by ponded water atop the junction after flooding occurs (sq. feet or sq. meters). If the Allow Ponding Simulation Option is turned on, a non-zero value of this parameter will allow ponded water to be stored and subsequently returned to the conveyance system when capacity exists. |
| Diverted Link | Name of link which receives the diverted flow. |
| Type | Type of flow divider. Choices are:
CUTOFF (all flow above a fixed value is diverted), OVERFLOW (all flow above the non-diverted conduit’s full depth flow is diverted), TABULAR (a diversion curve specifies diverted flow as a function of the total flow entering the divider), WEIR (diverted flow is linearly proportional to the total flow in excess of a given amount). |
| CUTOFFDivider | |
| - Cutoff Flow | Cutoff flow value used for a CUTOFF divider (flow units). |
| TABULARDivider | |
| - Curve Name | Name of Diversion Curve used with a TABULAR divider (double-click to edit the curve). |
| WEIR
Divider |
|
| - Min. Flow | Minimum flow at which diversion begins for a WEIR divider (flow units). |
| - Max. Depth | Vertical height of WEIR opening (feet or meters) |
| - Coefficient | Product of WEIR's discharge coefficient and its length. Weir coefficients are typically in the range of 2.65 to 3.10 per foot, for flows in CFS. |
B.6 Storage Unit Properties
| Name | User-assigned storage unit name. |
| X-Coordinate | Horizontal location of the storage unit on the Study Area Map. If left blank then the storage unit will not appear on the map. |
| Y-Coordinate | Vertical location of the storage unit on the Study Area Map. If left blank then the storage unit will not appear on the map. |
| Description | Optional description of the storage unit. |
| Tag | Optional label used to categorize or classify the storage unit. |
| Inflows | Click on the button and select Inflow to assign time series, dry weather, or RDII inflows to the storage unit. |
| Treatment | Click on the button and select Treatment to edit a set of treatment functions for pollutants entering the storage unit. |
| Invert El. | Elevation of the bottom of the storage unit (feet or meters). |
| Max. Depth | Maximum depth of the storage unit (feet or meters). |
| Initial Depth | Initial depth of water in the storage unit at the start of the simulation (feet or meters). |
| Ponded Area | Surface area occupied by ponded water atop the storage unit once the water depth exceeds the maximum depth (sq. feet or sq. meters). If the Allow Ponding analysis option is turned on, a non-zero value of this parameter will allow ponded water to be stored and subsequently returned to the drainage system when capacity exists. |
| Evap. Factor | The fraction of the potential evaporation from the storage unit’s water surface that is actually realized. |
| Shape Curve | Method of describing the geometric shape of the storage unit.
FUNCTIONAL shape uses the function Area = A*(Depth)^B + C to describe how surface area varies with depth. TABULAR shape uses a tabulated area versus depth curve. In either case, depth is measured in feet (or meters) and surface area in sq. feet (or sq. meters). |
| FUNCTIONAL | |
| - Coeff. | A-value in the functional relationship between surface area and storage depth. |
| - Exponent | B-value in the functional relationship between surface area and storage depth. |
| - Constant | C-value in the functional relationship between surface area and storage depth. |
| TABULAR | |
| - Curve Name | Name of the Storage Curve containing the relationship between surface area and storage depth (double-click to edit the curve). |
B.7 Conduit Properties
| Name | User-assigned conduit name. |
| Inlet Node | Name of node on the inlet end of the conduit (which is normally the end at higher elevation). |
| Outlet Node | Name of node on the outlet end of the conduit (which is normally the end at lower elevation). |
| Description | Optional description of the conduit. |
| Tag | Optional label used to categorize or classify the conduit. |
| Shape | Click on the button and select Conduit Shape to edit the geometric properties of the conduit's cross section. |
| Length | Conduit length (feet or meters). |
| Roughness | Manning’s roughness coefficient (see Section A.7 for closed conduit values or Section A.8 for open channel values). |
| Inlet Offset | Height of the conduit invert above the node invert at the upstream end of the conduit (feet or meters). |
| Outlet Offset | Height of the conduit invert above the node invert at the downstream end of the conduit (feet or meters). |
| Initial Flow | Initial flow in the conduit at the start of the simulation (flow units). |
| Entry Loss Coeff. | Head loss coefficient associated with energy losses at the entrance of the conduit. |
| Exit Loss Coeff. | Coefficient associated with energy losses at the exit of the conduit. |
| Avg. Loss Coeff. | Coefficient associated with energy losses along the length of the conduit. |
| Flap Gate
Diameter/Max Depth Number of Barrels Transect Max. Flow Shape Curve Forcemain Roughness Culvert Code |
YES if a flap gate exists which prevents backflow through the conduit, or NO if no flap gate exists.
Diameter for circular conduits and max depth for non-circular cross-sections. There is an operational setting that can be changed to enter circular conduits in units of inches or millimeters instead of feet and inches Enter the number of conduits with the same properties of invert elevation and cross-section that act together. If an Irregular section is chosen then choose or create a Transect that defines the cross-section Enter the maximum flow allowed in the conduit. Flow will only be limited if a non-zero value is entered. If the Custom Shape is chosen then a Shape Curve must be entered that defines the depth/full depth vs. width/full depth relationship. If a conduit is downstream of a pump and is expected to be pressurized, it is modeled as a forcemain and “Yes” should be chosen. If the conduit is specified as a forcemain, choose the Hazen-Williams or Darcy-Weisbach roughness factor. If a conduit is subject to inlet-control, you can specify it as a culvert. A culvert code of zero equates to no inlet control. Otherwise, codes 1-57 are available. |
B.8 Pump Properties
| Name | User-assigned pump name. |
| Inlet Node | Name of node on the inlet side of the pump. |
| Outlet Node | Name of node on the outlet side of the pump. |
| Description | Optional description of the pump. |
| Tag | Optional label used to categorize or classify the pump. |
| Pump Curve | Name of the Pump Curve which contains the pump’s operating data (double-click to edit the curve). |
| Initial Status | Status of the pump (ON or OFF) at the start of the simulation. |
B.9 Orifice Properties
| Name | User-assigned orifice name. |
| Inlet Node | Name of node on the inlet side of the orifice. |
| Outlet Node | Name of node on the outlet side of the orifice. |
| Description | Optional description of the orifice. |
| Tag | Optional label used to categorize or classify the orifice. |
| Type | Type of orifice (SIDE or BOTTOM). |
| Shape | Orifice shape (CIRCULAR or RECT_CLOSED). |
| Height | Height of orifice when fully open (feet or meters). Corresponds to the diameter of a circular orifice or the height of a rectangular orifice. |
| Width | Width of rectangular orifice when fully opened (feet or meters) |
| Crest Height | Height of bottom of orifice above invert of inlet node (feet or meters). |
| Discharge Coeff. | Discharge coefficient (unitless). A typical value is 0.65. |
| Flap Gate | YES if a flap gate exists which prevents backflow through the orifice, or NO if no flap gate exists. |
B.10 Weir Properties
| Name | User-assigned weir name. |
| Inlet Node | Name of node on inlet side of weir. |
| Outlet Node | Name of node on outlet side of weir. |
| Description | Optional description of the weir. |
| Tag | Optional label used to categorize or classify the weir. |
| Type | Weir type: TRANSVERSE, SIDEFLOW, V-NOTCH, or TRAPEZOIDAL |
| Height | Vertical height of weir opening (feet or meters) |
| Length | Horizontal length of weir opening (feet or meters) |
| Side Slope | Slope (width-to-height) of side walls for a V-NOTCH or TRAPEZOIDAL weir. |
| Crest Height | Height of bottom of weir opening from invert of inlet node (feet or meters). |
| Discharge Coeff. | Discharge coefficient for flow through the central portion of the weir (for flow in CFS when using US units or CMS when using SI units). Typical values are: 3.33 US (1.84 SI) for sharp crested transverse weirs, 2.5 - 3.3 US (1.38 - 1.83 SI) for broad crested rectangular weirs, 2.4 - 2.8 US (1.35 - 1.55 SI) for V-notch (triangular) weirs |
| Flap Gate | YES if the weir has a flap gate that prevents backflow, NO if it does not. |
| End Coeff. | Discharge coefficient for flow through the triangular ends of a TRAPEZOIDAL weir. See the recommended values for V-notch weirs listed above. |
| End Contractions | Number of end contractions for a TRANSVERSE or TRAPEZOIDAL weir whose length is shorter than the channel it is placed in. Either 0, 1, or 2 depending on if no ends, one end, or both ends are beveled in from the side walls. |
B.11 Outlet Properties
| Name | User-assigned outlet name |
| Inlet Node | Name of node on inflow side of outlet |
| Outlet Node | Name of node on discharge side of outlet |
| Description | Optional description of the outlet. |
| Tag | Optional label used to categorize or classify the outlet |
| Height | Height of outlet above inlet node invert (ft or m) |
| Flap Gate | YES if a flap gate exists which prevents backflow through the outlet, or NO if no flap gate exists. |
| Rating Curve | Method of defining flow (Q) as a function of head (h) across the outlet. A FUNCTIONAL curve uses a power function (Q = AhB) to describe this relation while a TABULAR curve uses a tabulated curve of flow versus head values. |
| FUNCTIONAL | |
| - Coefficient | Coefficient (A) for the functional relationship between head and flow rate. |
| - Exponent | Exponent (B) used for the functional relationship between head and flow rate. |
| TABULAR | |
| - Curve Name | Name of Rating Curve containing the relationship between head and flow rate (double-click to edit the curve). |
Categories: #INFOSWMM, InfoSWMM, InfoSWMM_SA, SWMM5