Rainfall Event Editor

The Rainfall Event Editor is used to display and edit rainfall intensity, and other associated data, measured during a rainfall event such as a storm.

The first page in the view allows editing of the rainfall hyetographs. The majority of the remaining pages are used to define initial conditions and profile data affecting rainfall runoff.

Solar radiation profile data used in water quality simulations when modelling coliform decay, dissolved algae or determinants dependent on dissolved algae is also defined in the rainfall event editor.

The pages are:

Further information on each of the pages in the Rainfall Event Editor can be found below:

Globals Page

InfoWorks networks only.

This page specifies global initial conditions for the current rainfall event for catchment runoff, catchment sediment and initial snow data. These conditions are applied to each subcatchment for which specific surface, subcatchment or snow pack initial conditions have not been defined.

Catchment Runoff Data (CRD), Catchment Sediment Data (CSD) and Initial Snow Data (ISD) are optional additional components of a rainfall event.

Catchment Runoff Data

InfoWorks networks only.

This section is used to define default initial values for the catchment runoff data.

The order of precedence for applying initial runoff conditions to subcatchments is as follows:

  • initial conditions specified on the Runoff Subcatchment, Units Subcatchment or ReFH Subcatchment pages
  • initial conditions defined on the Runoff Surface page
  • initial conditions defined on this page
  • initial conditions defined in the Rainfall Profile Properties of a rainfall profile
  • initial conditions defined in the Rainfall Sub-Event Properties of a rainfall sub-event

Note that catchment runoff data can be imported from an existing HydroWorks .CRD file by right-clicking on the rainfall event in the InfoWorks ICM Explorer or Explorer Window and selecting ImportFrom Event File.

Description A description of the initial condition.
UCWI Urban Catchment Wetness Index for the Wallingford Runoff Model
NAPI

API30 in mm for the New UK (Variable) Percentage Runoff Model and the UKWIR Runoff Model

Horton SMS Soil Moisture Store (SMS) in mm for the Horton Infiltration Model
Green-Ampt SMD Percentage Soil Moisture Deficit for the Green-Ampt Model
SCS Index Catchment wetness for the SCS, CN and CNSWMM runoff volume models
ReFH initial soil moisture content Cini value for the ReFH Runoff Model
ReFH initial baseflow per unit area BF0 value used by the ReFH Runoff Model.This global initial baseflow will be applied proportionally to each subcatchment within the catchment area.
ReFH subcatchment initial baseflow(used if initial baseflow per unit is unset) BF0 value used by the ReFH Runoff Model. This global initial baseflow will be applied to each subcatchment within the catchment area.
DefConLoss initial deficit

Initial deficit value for the Deficit and Constant Loss Model.

Indicates the amount of water required to saturate the soil layer to the maximum storage.

Initial UKWIR paved precipitation index PIpv value for the UKWIR Runoff Model
Delete CRD component button Click Delete CRD component to delete catchment runoff data.
Note: A user specified initial baseflow can be specified for each individual subcatchment using the ReFH Subcatchment tab. This value will take precedence over any ReFH value specified in the Globals tab.

Catchment Sediment Data

InfoWorks networks only.

This section is only relevant to Water Quality Simulations.

The information entered here determines the initial sediment mass on the catchment surface and the build-up time for which the Surface Pollutant Model or the SWMM Build-up/Washoff Land Use model is to be run before the start of the rainfall event. For the SWMM Build-up/Washoff Land Use model, the number of days since the last sweep can also be specified here.

The order of precedence for applying initial sediment mass values to subcatchments is as follows:

  • initial mass specified for the subcatchment on the Sediment Subcatchment page
  • initial mass for a Pollution Index defined on the Sediment Surface page and applied to the subcatchment via a Land Use definition
  • global initial mass defined on this page

Note that you can import catchment sediment data from an existing HydroWorks .CSD file by right-clicking on the rainfall event in the InfoWorks ICM Explorer or Explorer Window and selecting ImportEvent.

Note: If you do not include a Catchment Sediment Data component in a rainfall event used in a water quality simulation, the catchment surface will have no sediment on it at the start of the simulation. Not only have you not specified initial sediment depths, but you have not included a Buildup Time The Surface Pollutant Model will not calculate any sediment build-up prior to the start of the simulation.

Similarly, the SWMM Build-up/Washoff Land Use model will not be able calculate the any sediment build-up prior to the start of the simulation, nor will it calculate any sediment removal that may occur during the simulation if a Last Sweep is not specified.

Description

A description of the initial condition.

TSS Mass

The initial sediment mass (kg/ha) for the total suspended solids on the catchment surface.

If you do not specify a global value, it will be treated as zero.

It is good practice to always specify a global value, and then override specific instances as described below.

Buildup Time

The time (in hours) for which the Surface Pollutant Model is to be run, in order to calculate the sediment mass for each subcatchment at the start of the rainfall event.

Last Sweep (days) The number of days since the last sweep (surface removal of sediment) at the start of the event. This only applies to the SWMM Build-up/Washoff Land Use model.
Delete CSD component button Click on the Delete CSD component button to delete catchment sediment data.

Initial Snow Data

InfoWorks networks only.

Initial conditions for the Snow Melt Model are defined here. The values specified here apply to all subcatchments with Snow Packs in the network, unless values in the Snow Pack page or Snow Subcatchment page override them.

The order of precedence for applying initial snow data conditions to subcatchments is as follows:

  • initial conditions defined on the Snow Subcatchment page
  • initial conditions defined on the Snow Pack page
  • initial conditions specified on this page

Description

A description of the initial condition.

Snow Depth

Initial depth of snow. A value can be specified for each type of snowmelt surface.

Free Water

Initial depth of free water. A value can be specified for each type of snowmelt surface.

Delete ISD component button Click on the Delete ISD component button to delete initial snow data.

Runoff Surface Page

InfoWorks networks only.

This page specifies an initial runoff condition for different surface types. A runoff condition specified for surface type 1, for example, will apply to all subcatchments that use that surface type, unless initial runoff conditions have been defined for a particular subcatchment.

The definition of surface type initial runoff conditions is optional. However, if used, one record for each surface type that requires a specific initial runoff condition must be defined.

The order of precedence for applying initial runoff conditions to subcatchments is as follows:

Runoff Index The reference for this surface type. Any value between 1 and 99 is valid
UCWI Urban Catchment Wetness Index, defining the antecedent wetness of the catchment for use with the Wallingford runoff model
NAPI/PIpv

API30 for use with the New PR (New UK) runoff model and the UKWIR Runoff Model (Pervious surfaces).

Precipitation index for use with UKWIR Runoff Model (Paved surfaces).

Horton SMS The Soil Moisture Store representing the initial wetness of the catchment for use with the Horton runoff model.
Green-Ampt SMD The soil (initial) moisture deficit is the fraction difference between the soil porosity and actual moisture content, expressed as a percentage. For use with the Green-Ampt runoff model.
SCS Index Defines the catchment wetness for use with the SCS, CN and CNSWMM runoff volume models.
Def ConLoss initial deficit

Initial deficit value for the Deficit and Constant Loss Model.

Indicates the amount of water required to saturate the soil layer to the maximum storage.

Runoff Subcatchment Page

InfoWorks networks only.

This page defines a specific initial runoff condition index for a particular subcatchment. This condition will override any global or surface initial runoff condition that has been defined.

The definition of subcatchment initial conditions is optional. However, if used, one record for each subcatchment that requires a specific initial runoff condition must be defined.

The order of precedence for applying initial conditions to subcatchments is as follows:

Subcatchment label

The label of the subcatchment for which you are specifying the initial runoff condition for the subcatchment surface. An entry is required only if you are defining an initial condition for a specific subcatchment.

Surface 1 - 12 Initial condition

The initial runoff condition for the surface of the subcatchment specified.

The initial condition represents UCWI for the Wallingford Procedure and the SCS Index for the SCS, CN and CNSWMM runoff volume models.

The first field in this record applies to the whole subcatchment if values are not specified for any of the other surfaces.

Units Runoff Subcatchment Page

InfoWorks networks only.

This page defines a specific initial runoff condition for a particular subcatchment, where the initial condition is defined in depth units. This condition will override any global or surface initial runoff condition that has been defined.

The definition of subcatchment initial conditions is optional. However, if used, one record for each subcatchment that requires a specific initial runoff condition must be defined.

The order of precedence for applying initial conditions to subcatchments is as follows:

Subcatchment label

The ID of the subcatchment to which the initial runoff conditions will be applied. An entry is required only if initial conditions are to be defined for a specific subcatchment.

Surface 1 - 12 Initial condition

The initial runoff condition for the surface of the subcatchment specified.

The initial condition represents:

The first field in this record applies to the whole subcatchment if values are not specified for any of the other surfaces.

SUDS Subcatchment Page

InfoWorks networks only.

This page defines the initial saturation for the SUDS controls applied to a particular subcatchment. This condition will override the Initial saturation that has been defined in the subcatchment's SUDS controls data fields. All usages of a particular SUDS control in a given subcatchment will share the same initial conditions.

The definition of subcatchment SUDS initial conditions is optional.

Subcatchment

The ID of the subcatchment to which the SUDS controls will be applied. An entry is required only if initial conditions are to be defined for a specific subcatchment.

SUDS ID

The name of the SUDS controls object.
Initial saturation %

Depending on the type of SUDS control object, the initial saturation is either the degree to which soil in the Bio-retention cell, Rain garden or Green roof is initially filled with water, or, for all other types of SUDS controls, it corresponds to the degree to which their storage zone is initially filled with water.

ReFH Subcatchment Page

InfoWorks networks only.

This page defines ReFH runoff conditions for a particular subcatchment. This condition will override any global or surface initial runoff condition that has been defined.

The definition of subcatchment initial conditions is optional. However, if used, one record for each subcatchment that requires a specific initial runoff condition must be defined.

The order of precedence for applying ReFH initial conditions to subcatchments is as follows:

Subcatchment label

The ID of the subcatchment to which the initial runoff conditions will be applied. An entry is required only if initial conditions are to be defined for a specific subcatchment.

Soil Moisture Content

Initial conditions for ReFH Cini.

Baseflow Initial condition for ReFH BF0.

Sediment Subcatchment Page

InfoWorks networks only.

This section is only relevant to Water Quality Simulations.

This page defines specific initial sediment masses for particular subcatchments. The definition of subcatchment initial sediment masses is optional. This initial mass will override any global or surface initial sediment mass that has been defined elsewhere in the Catchment Sediment Data.

The order of precedence for applying initial masses to subcatchments is as follows:

Subcatchment label

The ID of the subcatchment to which the initial sediment mass will be applied. An entry is required only if initial conditions are to be defined for a specific subcatchment.

TSS Mass

The initial sediment mass (kg/ha) for the total suspended solids.

Sediment Surface Page

InfoWorks networks only.

This page specifies an initial sediment mass for a Pollution Index. The Pollution Index is associated with a specific subcatchment via the Land Use. Each Land Use has one Pollution Index associated with it, and the Pollution Index defines the surface washoff characteristics of the Land Use. The definition of pollution index initial sediment masses is optional.

A Pollution Index is defined in a Surface Definition Record on the Surface Pollutant Editor.

The order of precedence for applying initial masses to subcatchments is as follows:

Pollution Index

The reference for this surface type. Any value between 1 and 99 is valid.

This index is used on the Land Use Definition tab of the Land Use property sheet. The Land Use ID is referenced on the Surfaces tab of the Subcatchment property sheet.

TSS Mass

The initial sediment mass (kg/ha) for the total suspended solids.

Sweeping Page

InfoWorks networks only.

The page is used to define initial number of days since the last sweep (removal of sediment) for particular SWMM Build-up/Washoff Land Uses. The definition of these conditions is optional. The conditions defined here will override initial SWMM Build-up/Washoff Land Use conditions defined elsewhere in the Catchment initial conditions object.

The order of precedence for applying initial SWMM Build-up/Washoff Land Use conditions to subcatchments is as follows:

SWMM land use

The ID of the SWMM Build-up/Washoff Land Use which the initial conditions will be applied. An entry is required only if initial conditions are to be defined for a specific SWMM Build-up/Washoff Land Use.

Last sweep

The number of days since the last sweep (removal) of sediment.

Snow Pack Page

InfoWorks networks only.

The Snow Pack Page is used to define initial snow conditions for particular Snow Packs. The definition of snow pack initial snow conditions is optional. The conditions defined here will override initial snow data conditions defined elsewhere in the Rainfall Event Editor.

The order of precedence for applying initial snow data conditions to subcatchments is as follows:

Snow Pack label

The ID of the snow pack to which the initial snow data conditions will be applied. An entry is required only if initial conditions are to be defined for a specific snow pack.

Snow Depth

The initial snow depth for each of the three snow melt surface types for the snow pack.

Free Water Depth

The initial free water depth (depth of melted water held in the snow pack), for each of the three snow melt surface types for the snow pack.

Snow Subcatchment Page

InfoWorks networks only.

The Snow Subcatchment Page is used to define initial snow conditions for particular subcatchments. The definition of subcatchment initial snow conditions is optional. The conditions defined here will override initial snow data conditions defined elsewhere in the Rainfall Event Editor.

The order of precedence for applying initial snow data conditions to subcatchments is as follows:

Subcatchment label

The ID of the subcatchment to which the initial snow data conditions will be applied. An entry is required only if initial conditions are to be defined for a specific subcatchment.

Snow Depth

The initial snow depth for each of the three snow melt surface types for the subcatchment.

Free Water Depth

The initial free water depth (depth of melted water held in the snow pack), for each of the three snow melt surface types for the subcatchment.

Temperature Data Page

The Temperature Data Page is used to enter profiles of air temperature for use in:

For SWMM networks, one or more temperature profiles may be defined, however, only the first temperature profile included in the rainfall event is applied to all rainfall gauges in the event.

For InfoWorks networks, one or more temperature profiles may be defined:

Wind Data Page

InfoWorks networks only.

The Wind Data Page is used to enter a profile of wind speed for use in modelling snow melt. See the Snow Melt Model topic for more information on the use of this profile.

A single wind profile may be entered.

Evaporation Data Page

The Evaporation Data Page is used to define evaporation profiles to be applied to the Rainfall Event.

The order of precedence for applying evaporation data is as follows:

One or more evaporation profiles may be defined:

Note: If an evaporation profile starts after the Rainfall Event start time, evaporation of 0 mm/day will be assumed until the evaporation profile start time. If the Rainfall Event lasts longer than the evaporation data, the evaporation will drop to 0 mm/day one evaporation timestep after the end of the evaporation data.

Solar Radiation Page

InfoWorks networks only.

The Solar Radiation Page is used to define a solar radiation profile to be applied when modelling:

A single solar radiation profile may be entered.

Soil Moisture Deficit Data Page

InfoWorks networks only.

The Soil Moisture Deficit Data Page is used to define soil moisture deficit profiles, which are used to calculate effective rainfall for subcatchments that use the SRM runoff volume model.

Any subcatchment that uses the SRM runoff volume model and has its Soil moisture deficit field set to Event should have a corresponding soil moisture deficit profile.

Parent topic: Events Interface

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