User Defined Defaults

Inflow

The inflow distributed according to the conduit length. For example, a value of 0.00001 m3s-1m-1 sets an inflow of 0.00123 m3s-1 for a 123 metre long conduit.

• If the Inflow is lateral simulation parameter is checked, the simulation engine applies this inflow value laterally along the link.
• If the Inflow is lateral parameter is not checked, the simulation engine applies this inflow value to the node at the end of the link with the highest invert level. In the case of equal invert levels, the flow is assigned to the upstream node.

inflow

Double

CI

8

0

0

0

US Headloss Type

The default headloss condition at the upstream end of the link. InfoWorks ICM provides built-in headloss type options, or a user defined headloss curve may be defined.

See the Headloss Curves topic for further information on the headloss type options:

Database Value	Description
FHWA	Headloss is calculated based on the FHWA Inlet and Access Hole Energy Loss method as described in the FHWA HEC 22 Urban Drainage Manual. Appropriate for closed conduits connected to manholes. IMPORTANT In order to use the FHWA headloss condition for networks created in versions of InfoWorks ICM prior to version 3.5, it is necessary to validate the network. Validating the network will update the built-in headloss curves to include the FHWA curve type.
FIXED	Headloss is calculated using a built-in headloss curve. Appropriate for situations when there is a known headloss, such as entry into a reservoir or an open channel with bends.
HIGH	Headloss is calculated using a built-in headloss curve. Appropriate for badly connected manholes that are benched only to half pipe height.
NONE	No headloss assumed
NORMAL	Headloss is calculated using a built-in headloss curve. Appropriate for well-constructed manholes on pipe systems, or for small open channel systems.

us_headloss_type

Text

64

0

Normal

US Headloss Coefficient

The default multiplying factor for the standard headloss coefficient to represent additional losses due to bends or bad construction causing extra headloss. The list below shows some recommended values.

us_headloss_coeff

Double

2

1

0

Headloss Type

see Upstream Headloss Type

ds_headloss_type

Text

64

0

Normal

Headloss Coefficent

see Upstream Headloss Coefficient

ds_headloss_coeff

Double

2

1

0

Roughness Type

Choose either CW (Colebrook-White) or Manning equations for hydraulic roughness.

roughness_type

Text

7

0

CW

Top Roughness CW

The default roughness value for the top two-thirds of the conduit.

top_roughness_CW

Double

RCW

3

1.5

0.1

999

Bottom Roughness CW

The default roughness value for the bottom third of the conduit. You must enter a value here. This value acts as the default roughness for the whole conduit if you do not give a value for the top two-third

bottom_roughness_CW

Double

RCW

3

1.5

0.1

999

Top Roughness HW

The default roughness value for the top two-thirds of the conduit.

top_roughness_HW

Double

3

20

5000

50

Bottom Roughness HW

The default roughness value for the bottom third of the conduit. You must enter a value here. This value acts as the default roughness for the whole conduit if you do not give a value for the top two-third

bottom_roughness_HW

Double

3

20

5000

50

Top Roughness Manning's 1/n

The default roughness value for the top two-thirds of the conduit.

top_roughness_Manning

Double

3

25

0.001

999

Bottom Roughness Manning's 1/n

The default roughness value for the bottom third of the conduit. You must enter a value here. This value acts as the default roughness for the whole conduit if you do not give a value for the top two-third

bottom_roughness_Manning

Double

3

25

0.001

999

The default roughness value for the top two-thirds of the conduit.

Sediment Depth

The default depth of permanent, consolidated sediment in the conduit. Note that the transport of this sediment through the system is not modelled.

sediment_depth

Double

PS

0

0

0

1D diffusion type

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

Default type of 1d diffusion can be set to either River or Estuary.

Set to Estuary to calculate a diffusion coefficient that varies with tidal discharge and/or the longitudinal salinity gradient, or set to River to calculate a diffusion coefficient that is related to shear velocity.

Used for 1D diffusion water quality simulations only.

diff1_type_cont

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - d0 is a constant which is used to prevent unrealistically low values of dispersion from arising.
• River - d0 is the minimum diffusion coefficient.

The value of d0 must be ≥0 (m2/s).

Used for 1D diffusion water quality simulations only.

diff1_d0_cont

1D diffusion d1

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - then d1 is a constant which represents the amount of dispersion caused by tidal mixing in the estuary
• River - d1 is the shear velocity factor.

The value of d1 must be ≥0 for rivers or ≥ 0 1/m for estuaries.

Used for 1D diffusion water quality simulations only.

diff1_d1_cont

0

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

This field is only enabled when 1D diffusion type is set to Estuary.

d2 is a constant which determines the effect of salinity gradient on dispersion. The value of d2 must be ≥0 m6/(kg/s).

Used for 1D diffusion water quality simulations only.

diff1_d2_cont

Flood Type

Choose one of the following from the dropdown list:

• Sealed. The water level can rise indefinitely without any flooding occurring.
• Stored. The flood water on the catchment surface is retained in the storage volume defined by the flood levels and areas specified below. The flood water returns to the drainage system as the levels drop.
• Lost. Flood water is lost from the system.
• Gully. The flood water on the catchment surface is retained in a storage volume defined in the Level / Plan Area Grid on the Storage Parameters Page. The discharge between surface storage and manhole is defined by a Head Discharge Table.
• 2D. The discharge between surface storage (on the 2D mesh) and manhole is calculated using standard weir equations, where the weir width is taken as the circumference of the manhole.
• Gully 2D. The discharge between surface storage (on the 2D mesh) and manhole is defined by a Head Discharge Table.
• Inlet. The discharge between surface storage and manhole is defined by user defined inlet parameters. See Inlet Nodes for further details.
• Inlet 2D. The discharge between surface storage (on the 2D mesh) and manhole is defined by user defined inlet parameters. See Inlet Nodes for further details.

flood_type

Text

6

0

Stored

Flood Area 1 (%)

The default percentage of the floodable area acting as the first part of a double conical flood storage volume. The first cone extends from the manhole area at ground level to this area at flood level 1

flood_area_1

0

10

0

100

Flood Area 2 (%)

The default percentage of the floodable area acting as the second part of a double conical flood storage volume. The second cone extends from flood area 1 at flood level 1 to this area at flood level 2

flood_area_2

0

100

0

100

Flood Depth 1

The default depth at which the flood water spreads over flood area 1

flood_depth_1

Double

Y

1

1

0

Flood Depth 2

The default depth at which the flood water spreads over flood area 2

flood_depth_2

Double

Y

1

99

0

2D element area factor

Multiplying factor applied to manhole shaft plan area to determine effective area of a 2D manhole.

The effective area is used when creating a 2D mesh to ensure that flow feeding into each 2D manhole comes from a single element.

Mesh triangles at each 2D manhole will be aggregated to form an element with an area that is at least the effective area of the manhole.

element_area_factor_2d

Double

1

1

1

Benching method options:

Access hole benching methods (Figure 7-6 FHWA HEC 22 Urban Drainage Manual)

Choose the basis for the transfer of flow from the dropdown list:

• Depth to use the depth in 2D zones to set the water level at nodes connected to the 2d zone. This is the recommended approach where the ground model is consistent with the specified elevation of the node.
• Elevation to use the elevation in 2D zones to set the water level at nodes connected to the 2D zone. This may help to avoid oscillating flows caused by ground level discrepancy between manholes and 2D mesh elements.

If left blank, the setting of Use 2d elevations instead of depths field in the simulation parameters is used.

2d_link_type

Text

12

0

Depth

Inflow

The inflow distributed according to the channel length. For example, a value of 0.00001 m3s-1m-1 sets an inflow of 0.00123 m3s-1 for a 123 metre long channel.

• If the Inflow is lateral simulation parameter is checked, the simulation engine applies this inflow value laterally along the link.
• If the Inflow is lateral parameter is not checked, the simulation engine applies this inflow value to the node at the end of the link with the highest invert level. In the case of equal invert levels, the flow is assigned to the upstream node.

inflow

Double

CI

8

0

0

0

US Headloss Type

The default headloss condition at each end of a channel. Choose one of the following built-in conditions from the dropdown list:

• High (uses the high headloss curve for surcharge ratio)

• None (no headloss)

• Normal (uses the normal headloss curve for surcharge ratio)

us_headloss_type

Text

64

0

Fixed

US Headloss Coefficient

The default multiplying factor for the standard headloss coefficient to represent additional losses due to bends or channel irregularities causing extra headloss. The list below shows some recommended values.

us_headloss_coeff

Double

2

0

0

DS Headloss Type

The default headloss condition at each end of a channel. Choose one of the following built-in conditions from the dropdown list:

• High (uses the high headloss curve for surcharge ratio)

• None (no headloss)

• Normal (uses the normal headloss curve for surcharge ratio)

ds_headloss_type

Text

64

0

Fixed

DS Headloss Coefficent

The default multiplying factor for the standard headloss coefficient to represent additional losses due to bends or channel irregularities causing extra headloss. The list below shows some recommended values.

ds_headloss_coeff

Double

2

0

0

Roughness Type

Choose either CW (Colebrook-White) or Manning equations for hydraulic roughness.

roughness_type

Text

7

0

CW

Sediment Depth

The default depth of permanent, consolidated sediment in the channel. Note that the transport of this sediment through the system is not modelled.

sediment_depth

Double

PS

0

0

0

1D diffusion type

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

Default type of 1d diffusion can be set to either River or Estuary.

Set to Estuary to calculate a diffusion coefficient that varies with tidal discharge and/or the longitudinal salinity gradient, or set to River to calculate a diffusion coefficient that is related to shear velocity.

Used for 1D diffusion water quality simulations only.

diff1_type_cont

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - d0 is a constant which is used to prevent unrealistically low values of dispersion from arising.
• River - d0 is the minimum diffusion coefficient.

The value of d0 must be ≥0 m2/s.

Used for 1D diffusion water quality simulations only.

diff1_d0_cont

1D diffusion d1

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - then d1 is a constant which represents the amount of dispersion caused by tidal mixing in the estuary
• River - d1 is the shear velocity factor.

The value of d1 must be ≥0 for rivers or ≥0 1/m for estuaries.

Used for 1D diffusion water quality simulations only.

diff1_d1_cont

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

This field is only enabled when 1D diffusion type is set to Estuary.

d2 is a constant which determines the effect of salinity gradient on dispersion. The value of d2 must be ≥0 m6/(kg/s).

Used for 1D diffusion water quality simulations only.

diff1_d2_cont

Inflow

The inflow distributed according to the link length. For example, a value of 0.00001 m3s-1m-1 sets an inflow of 0.00123 m3s-1 for a 123 metre long link.

If the Inflow is lateral simulation parameter is checked, the simulation engine applies this inflow value laterally along the link.

If the Inflow is lateral parameter is not checked, the simulation engine applies this inflow value to the node at the end of the link with the highest invert level. In the case of equal invert levels, the flow is assigned to the upstream node.

inflow

Double

CI

8

0

0

0

US headloss type

The default headloss condition at each end of the link. Choose one of the following built-in conditions from the dropdown list:

• High (uses the high headloss curve for surcharge ratio)

• None (no headloss)

• Normal (uses the normal headloss curve for surcharge ratio)

us_headloss_type

Text

64

0

Fixed

US headloss coefficient

The default multiplying factor for the standard headloss coefficient to represent additional losses due to bends or channel irregularities causing extra headloss. The list below shows some recommended values.

us_headloss_coeff

Double

2

0

0

DS headloss type

The default headloss condition at each end of a link. Choose one of the following built-in conditions from the dropdown list:

• High (uses the high headloss curve for surcharge ratio)

• None (no headloss)

• Normal (uses the normal headloss curve for surcharge ratio)

ds_headloss_type

Text

64

0

Fixed

DS headloss coefficient

The default multiplying factor for the standard headloss coefficient to represent additional losses due to bends or channel irregularities causing extra headloss. The list below shows some recommended values.

ds_headloss_coeff

Double

2

0

0

Sediment depth

The default depth of permanent, consolidated sediment in the channel. Note that the transport of this sediment through the system is not modelled.

sediment_depth

Double

PS

0

0

0

The default value of active layer thickness.

Applicable when Active layer depth method in Water Quality and Sediment Parameters is set to Explicit.

The default multiplying factor for calculating active layer thickness.

Applicable when Active layer depth method in Water Quality and Sediment Parameters is set to D50 or D90.

1D diffusion type

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

Default type of 1d diffusion can be set to either River or Estuary.

Set to Estuary to calculate a diffusion coefficient that varies with tidal discharge and/or the longitudinal salinity gradient, or set to River to calculate a diffusion coefficient that is related to shear velocity.

Used for 1D diffusion water quality simulations only.

diff1_type_cont

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - d0 is a constant which is used to prevent unrealistically low values of dispersion from arising.
• River - d0 is the minimum diffusion coefficient.

The value of d0 must be ≥0 m2/s.

Used for 1D diffusion water quality simulations only.

diff1_d0_cont

1D diffusion d1

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

If 1D diffusion type is set to:

• Estuary - then d1 is a constant which represents the amount of dispersion caused by tidal mixing in the estuary
• River - d1 is the shear velocity factor.

The value of d1 must be ≥0 for rivers or ≥0 1/m for estuaries.

Used for 1D diffusion water quality simulations only.

diff1_d1_cont

Water Quality

This section is relevant only to Water Quality Simulations. If the icon is at the start of a paragraph, then that paragraph is only relevant to water quality simulations. If the icon is at the top of a topic, or a section (underneath a section title), or a row in a table, then the complete topic, section or row is only relevant to water quality simulations.

This field is only enabled when 1D diffusion type is set to Estuary.

d2 is a constant which determines the effect of salinity gradient on dispersion. The value of d2 must be ≥0 m6/(kg/s).

Used for 1D diffusion water quality simulations only.

diff1_d2_cont

Area Measurement Type

Choose either Absolute or Percent from the dropdown list. If you choose Absolute, the area for each surface type is a value in hectares. If you choose Percent, the area for each surface type is a percentage of the contributing area.

area_measurement_type

Text

8

0

Absolute

Rainfall Profile

The default rainfall profile, where you have a rainfall file containing records from several rain gauges to represent spatial variation.

rainfall_profile

Text

64

0

1

Source of soil class SPR values, which can be used to determine Standard percentage runoff for use with the UKWIR Model.

WRAP soil type

Choose the class number from the dropdown list. Essential for the Wallingford Procedure UK runoff model.

May be used to provide Standard percentage runoff values for the UKWIR Model.

soil_class

Long Integer

0

2

1

5

Base Flow

The default base infiltration flow into the system, distributed by catchment area. It is a constant inflow. If you import a HydroWorks network, InfoWorks ICM will set this value to the original value for default infiltration in the .DSD file. Any local base flow for a subcatchment overrides this figure

base_flow

Double

IF

5

0

0

0

Additional Foul Flow

The additional flow, distributed by catchment area. It is added to the nominal wastewater flow (NWF) draining into the system (NWF = per capita flow x population x connectivity). The time-varying multiplier from the wastewater profile applies to the total wastewater flow (total wastewater flow = NWF plus additional foul flow). Any local additional foul flow for a subcatchment overrides this figure

additional_foul_flow

Double

IF

5

0

0

0

Land Use ID

The default land use. The land use definition contains default values for various subcatchment parameters. Select a land use from the dropdown list

land_use_id

Text

64

0

1

Rainfall profile

The default rainfall profile, where you have a rainfall file containing records from several rain gauges to represent spatial variation

Built-in default = 1

rainfall_profile

Text

64

0

1

Choose the default type of meshing to be used for generating the mesh from the dropdown list:

• Classic - The classic meshing approach that has been present in InfoWorks ICM since it was first released.
• Clip meshing - The clip meshing approach that makes use of primary and secondary meshing phases. It is particularly suited to models with complex geometry and objects that may be approximately coincident.

See 2D Mesh Generation Methodology for further information about these two meshing types.