Foul Runoff can only be defined in Foul phases.
The resulting flow from the foul runoff is made up of three parts: Industrial flow runoff from the catchment area, Domestic flow runoff from the catchment area, and Foul flow from dwellings.
Resulting Flow = Industrial flow rate + Domestic flow rate + flow rate from either Discharge Unit or Main Drainage.
The flow from the industrial portion of the development is calculated by:
Industrial flow rate = Catchment Area x Industrial Peak Flow Factor x Industrial Flow
The flow from the domestic portion of the development is calculated by:
Domestic flow rate = Catchment Area x Domestic Peak Flow Factor x Domestic Flow
Foul flow from dwellings can be calculated using either the Discharge Unit method or the Main Drainage method.
Discharge Unit foul flow calculation:
Foul flow rate = SQRT( Total Discharge Units) * Frequency Factor
Main Drainage foul flow calculation:
Foul flow rate = (Flow Per Dwelling * Number of Dwellings) / 86400
Industrial Flow (checkbox) - Check to include industrial flow.
Industrial Flow (textbox) - The amount of industrial flow per unit area.
Industrial Peak Flow Factor - A factor to apply to the industrial flow to account for the peak flow.
Domestic Flow (checkbox) - Check to include domestic flow.
Domestic Flow (textbox) - The amount of domestic flow per unit area.
Domestic Peak Flow Factor - A factor to apply to the domestic flow to account for the peak flow.
Calculation Method - The method used to calculate flow. Available options are Discharge Unit and Main Drainage.
Total Discharge Units - The total of all discharge units. Editable manually or via the Total Discharge Units Calculator.
Frequency Factor - Factor applied in calculating flow.
Flow per Dwelling - The total flow for a single dwelling. Editable manually or via the Flow per Dwelling Calculator.
Number of Dwellings - The total number of dwellings.
Resulting Flow Rate - The total flow calculated.