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    • Greenfield runoff rate estimation
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    Here are our tools for the design and evaluation of SuDS

    • Tools
    • Greenfield runoff rate estimation
    • Surface water storage volume estimation
    • Infiltration volume estimation
    • SuDS performance evaluation tool
    • Water quality assessment for SuDS developments (SuDS manual)
    • Water quality assessment for SuDS developments (WaND)
  • Training & support

    We provide SuDS training courses and support for drainage consultants and local planning authorities.

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  • SuDS-iQ
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Why are greenfield flow rates used for setting the limit of discharge and why is the default flow rate 3 l/s/ha?

  • Read more about Why are greenfield flow rates used for setting the limit of discharge and why is the default flow rate 3 l/s/ha?

What is urban creep?

  • Read more about What is urban creep?

What is the ‘total site area’, ‘non-contributing area’ and ‘contributing area’ within the surface water storage volume design tool?

  • Read more about What is the ‘total site area’, ‘non-contributing area’ and ‘contributing area’ within the surface water storage volume design tool?

What are the ‘betterment’ and ‘relaxation’ methods provided for previously developed sites?

  • Read more about What are the ‘betterment’ and ‘relaxation’ methods provided for previously developed sites?

What limiting discharge flow rate should be used for previously developed sites?

  • Read more about What limiting discharge flow rate should be used for previously developed sites?

Does the estimation of the greenfield runoff rate take into account steep sites?

  • Read more about Does the estimation of the greenfield runoff rate take into account steep sites?

How to obtain BFI / BFIHOST value?

  • Read more about How to obtain BFI / BFIHOST value?

How to obtain SPR / SPRHOST value?

  • Read more about How to obtain SPR / SPRHOST value?

What is Qmed and the FEH statistical equation?

  • Read more about What is Qmed and the FEH statistical equation?

What is Qbar and the IH124 formula?

  • Read more about What is Qbar and the IH124 formula?

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