Drainage Category (Drainage)

• Point Devices
  • Catchment (Catchments, List(Of ObjectId)) - contains the names of the catchments associated with the device
  • Contribution Area (ContributionArea, Double) - Sum of the areas of the Catchments associated with the device
  • Total Area (TotalArea, Double) - sum of all areas connected to the device and areas connected upstream of this
    AreaTotal = AreaContr + Sum(AreaTotal of amount)
  • Coefficient of runoff (C, Double) - also called coefficient of impermeability (0 < C = 1)
    If you have more than one area connected to the device, a weighted average will be calculated for each area
  • Coefficient of delay (Cr, Double) - reducing factor for very large catchments
    Cr = (Total Area in hectares) ^ ( - nCr)
    nCr is tabulated according to the Contribution Area (see Standards / drainage / Delay Coefficient)
  • Distribution Coefficient (nCr, Double) used in CR calculation
  • Sum of CXA (SCXA, Double) - Sum of (contribution area) multiplied by its (C Coefficient)
    SCxA = Sum (C * Area)
  • Time of concentration (Tc, Double) - Time it takes for the most distant particle to reach the discharge point
    Depends on the Tc of the associated basins and the adopted TcMin (see Standards/Drainage/TcMin)
• Linear or Longitudinal Devices
  • Section Height (D, Double) - Hydraulic Section Height
• Longitudinal Devices
  • Catchment (Catchments, List(Of ObjectId)) - contains the names of the catchments associated with the device
  • Characteristic Width (EquivalentWidth, Double) - Characteristic width of the surface flow path
    EquivalentWidth = ContributionArea / Length2D