Cover of Hydrology Update to the Austroads Guide to Road Design Part 5
Hydrology Update to the Austroads Guide to Road Design Part 5
  • Publication no: AP-R683-23
  • ISBN: 978-1-922700-74-2
  • Published: 31 March 2023

This report documents the changes to Section 6 – Hydrology of Austroads Guide to Road Design Part 5: Drainage – General and Hydrology Considerations. Section 6, which covers design related knowledge and guidance on hydrology and hydraulics in road design, required a significant update due to the volume of new work and methodology that has been adopted as part of the recent release of Australian Rainfall and Runoff 2019.

  • Summary
  • 1. Introduction
    • 1.1 Purpose
    • 1.2 Methodology
  • 2. Summary of Update
    • 2.1 Terminology
    • 2.2 Catchment Hydrology
    • 2.3 Probability and Risk
    • 2.4 Data for Drainage Design
    • 2.5 Hydrology Methods for Road Drainage and Flood Design
      • 2.5.1 Direct Rainfall
      • 2.5.2 Rational Method
      • 2.5.3 Regional Flood Frequency Estimation (RFFE)
    • 2.6 Design Inputs
      • 2.6.1 Australian Rainfall and Runoff Data Hub
      • 2.6.2 Rainfall Inputs
    • 2.7 Design Software
    • 2.8 Very Rare and Extreme Events
    • 2.9 Specific Design Issues
      • 2.9.1 Flood Impact Criteria
      • 2.9.2 Flooding for Tunnel Portals
    • 2.10 Safety in Design
    • 2.11 Climate Change
      • 2.11.1 Climate Change
      • 2.11.2 Climate Change and Sea Level Rise
    • 2.12 Joint Probability
    • 2.13 Time of Submergence and Closure
      • 2.13.1 Definition of Road Flooding
      • 2.13.2 Calculation of Average Annual Time of Closure
    • 2.14 Uncertainty
    • 2.15 Examples
  • References