Road design

Cover of Guide to Road Design Part 5: Drainage-General and Hydrology Considerations
Guide to Road Design Part 5: Drainage-General and Hydrology Considerations
  • Publication no: AGRD05-13
  • ISBN: 978-1-925037-01-2
  • Published: 22 May 2013
  • Edition: 3.1

Guide to Road Design Part 5: Drainage – General and Hydrology Considerationsprovides road designers and other practitioners with guidance on the design of drainage systems.

This Guide needs to be used in conjunction with the other two Parts of the Guide to Road Designthat relate to drainage design:

  • Guide to Road Design Part 5A: Drainage – Road Surface, Network, Basins and Subsurface
  • Guide to Road Design Part 5B: Drainage – Open Channels, Culverts and Floodways.

This Guide provides information on the elements that need to be considered in the design of a drainage system. Guidance is provided on the safety aspects of stormwater flows, environmental considerations and water sensitive treatments within a drainage system.

Drainage considerations are outlined covering the determination of the flood immunity, freeboard to be used for the design, types of structures, and operational and maintenance requirements.  The hydrologic assessment provides guidance on rainfall intensities, run-off coefficients and determining the design discharges.

Design processes and formulae necessary to design effective drainage systems and infrastructure are included. It is supported by appendices containing design charts and worked examples.

This Guide outlines good practice in relation to drainage design that will apply in most situations, rather than specifying mandatory practice.

Edition 3.1 corrects Equation A1 in Appendix A.

In 2013 Guide to Road Design Part 5: Drainage Design was substantially expanded and republished in three parts: Guide to Road Design Part 5: Drainage – General andHydrology Considerations; Guide to Road Design Part 5A: Drainage – Road Surface, Networks, Basins and Subsurface; and Guide to Road Design Part 5B: Drainage – Open Channels, Culverts and Floodways.