The Total Volume value shown in the bottom-right corner of the data form shows the volume available in the system up to the Freeboard level.
The depth within the stormwater control is determined from two of the following three parameters, with the third automatically calculated based on the option selected:
Freeboard - Controls how close to the specified Exceedence Level the water must reach before the Status (on the Summary) shows Flood Risk.
Soakaway shape - Rectangular / Square / Circular.
Width (Rectangular and Square shapes) - Width of soakaway.
Diameter (Circular shape) - Diameter of soakaway.
Length (Rectangular shape) - Diameter of soakaway.
Void Ratio - The percentage of the storage volume that is available for storage. This is dictated by the type of fill material that is used. I.e. Typically 30% for rubble.
Ineffective Storage Depth - The depth below the exceedence level that is unavailable for the storage of water.
Ineffective Infiltration Depth - The depthe below the exceedence level that is unavailable for the (side) infiltration of water.
Number Of Soakaways - The number of soakaways required.
Base Infiltration rate - Defines the rate of infiltration through the base of the filter area. This should be determined from a performance site test.
Side Infiltration rate - Defines the rate of infiltration through the sides of the filter area. This should be determined from a performance site test.
The Sizing Calculator option allows the user to re-size the Soakaway by specifying a volume and a parameter to modify to achieve that volume. The Sizing Calculator is discussed in more detail in the Stormwater Control Sizing Calculator section.
Explore the Inlets page for more details on the different types of Inlets that can be specified.
Explore the Outlets page for more details on the different types of Outlets that can be specified.
Pollution Name - Name of pollutants. This is populated based on the Pollutants set up as part of the Site Data.
Background Concentration - Value below which the pollution concentration cannot fall during analysis. When concentration reaches this level, no further removal occurs.
Percentage Removal - Available if Percentage Removal entered. The value entered will be deducted from the Inflow into the system.
τ - The decay time constant or (mean) lifetime of the pollutant. It can be entered manually or calculated from the decay constant or decay half-life. See Pollutant Removal Method - First Order Decay for more details.
Stormwater Control Types
These systems can be customized to represent a variety of drainage or treatment facilities. Please review the description of each system to see which one would be the most convenient to use.
Workflow - What's next...?