The approach for each Hydraulics Manual is to conduct a comprehensive evaluation of current hydrologic and hydraulic engineering practices and, where appropriate, recommend revised drainage practices.
In 2005, Jorgensen completed a NCHRP project to revise and update the AASHTO Model Drainage Manual and the AASHTO Highway Drainage Guidelines. In July 2012, Jorgensen completed an update to the Model Drainage Manual, published by AASHTO in 2014. For the 2014 AASHTO Drainage Manual, Jorgensen and Phil Thompson worked with the AASHTO Technical Committee on Hydrology and Hydraulics to prepare a new nationwide document that supersedes the Model Drainage Manual. The new ADM is segregated into two volumes — one for Policies and one for Procedures. Jorgensen used the vast FHWA library on hydraulics, synthesizing the material and compiling a practitioner’s handbook on all major drainage topics (e.g., hydrology, channels, culverts, bridges, storm drainage systems, energy dissipators, bank protection). In addition, the Team performed a major edit of the text and prepared all graphics to meet the specifications for AASHTO publications.