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Hydraulics Manual

Various types of drainage facilities are required to move water under, along or away from a highway. These facilities must be economical and efficient, as well as possess the capacity to do so without damaging the highway or endangering motorists.

The Hydraulics Manual provides hydrologic and hydraulic analysis procedures for most situations encountered in highway design.

Please contact the Hydraulics Engineering Unit should a situation arise that is not described in this manual. Requesting assistance as soon as questions or problems arise is highly encouraged, as it will allow for the time needed to develop a satisfactory solution and likely reduce the amount of redesign needed.

Hydraulics Design Manual, 2014 (91 MB)

​Manual changes are effective Aug. 1, 2014. These changes supersede all pervious versions and apply to new design projects as of this date.

  • Changes were made to chapters 3, 4, 5, 6, 12, 13,14 and 17.
  • New guidance was added to chapter 18.

Edits within the existing chapters are shown in blue highlight.

New chapters or appendices are highlighted in green.

Technical guidance may be issued between official updates to this manual. Bulletins are intended to provide immediate technical guidance on processes, procedures and design information for users until the manual is updated, at which time bulletins may be incorporated into the Hydraulics Manual.

New ODOT-designed projects include those which do not have an approved DAP by the effective date noted above. New outsourced projects include those that do not have an executed work order contract for PE by the effective date noted above. However, existing projects may make use of the new changes, if agreed to by the CPM or project team.