The manual is available on-line at the following address:

http://www.dot.ca.gov/hq/oppd/hdm/hdmtoc.htm

The fifth edition of the manual was a technical update and conversion of the manual from Imperial Units to Metric SI units. Hard paper copy can be purchased from the Publications Unit at the address below. Thank you for your interest.

http://caltrans-opac.ca.gov/publicat.htm