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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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What is a critical duration rainfall event?

  • Read more about What is a critical duration rainfall event?

What is Qbar?

  • Read more about What is Qbar?

What runoff model and runoff coefficients should be used?

  • Read more about What runoff model and runoff coefficients should be used?

What soil parameters and values should be used in the greenfield runoff equations?

  • Read more about What soil parameters and values should be used in the greenfield runoff equations?

Why do I need to manually enter the Q1, Q30 and Q100 values when using the ReFH2 method?

  • Read more about Why do I need to manually enter the Q1, Q30 and Q100 values when using the ReFH2 method?

Why is greenfield runoff rate and volume linked?

  • Read more about Why is greenfield runoff rate and volume linked?

Why is the 1:100 year greenfield runoff volume control criterion important?

  • Read more about Why is the 1:100 year greenfield runoff volume control criterion important?

Why is the Interception criterion so important?

  • Read more about Why is the Interception criterion so important?

How is greenfield or previously developed site runoff calculated when only a proportion of the site is urbanised?

  • Read more about How is greenfield or previously developed site runoff calculated when only a proportion of the site is urbanised?

How is the peak runoff rate from a previously developed site calculated?

  • Read more about How is the peak runoff rate from a previously developed site calculated?

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