Highway Design Manual
The Highway Design Manual (HDM) establishes uniform policies and procedures to carry out the state highway design functions of the California Department of Transportation. Refer to the "Foreword" section of the HDM for more information.
Highway Design Manual Change Transmittals are posted by change date and include a summary of the significant changes. Implementation of the current version of the HDM shall be applied to on-going projects in accordance with HDM Index 82.5, unless otherwise noted on the Manual Change Transmittal memo or by separate Design Memo.
No matter which of the formats is used to download and/or print, if the HDM Holder chooses to do so, the Holder is responsible for keeping their electronic and/or paper copy up to date and current. For this reason, HDM Holders are encouraged to use the on-line version of the HDM for the most current design guidance.