Design Manuals and Supplements
Proposed Changes to PDDM
A new draft of the entire PDDM has been posted. All chapters have formatting changes, typo fixes, link updates, and units rearranged as US Customary [Metric]. The following chapters of the PDDM have additional draft changes awaiting comment and approval:
Chapter 1: INTRODUCTION
The following changes are proposed:
- Section 1.1.4 - Modified text to state that the PDDM is published in US Customary units with SI units in square brackets (the reverse of the original convention)
- Section 1.1.5 - Changed FDL to FLH Discipline Champion (or Champion for short). Removed FDL from Section 1.4.1 abbreviation listing.
- Section 1.2.5 - Removed link to Clearview Typeface since this has not been generally approved by FHWA.
Chapter 3: ENVIRONMENTAL STEWARDSHIP
The following changes are proposed:
- Removed links from obsolete documents.
Chapter 4: CONCEPTUAL STUDIES AND PRELIMINARY DESIGN
The following changes are proposed:
- Used section numbers to refer to the 2011 Green Book
- Section 4.3.2.3 - modified definitions
- Section 4.6 to 4.6.2 - updated text
- Section 4.7.1.1 - added sentence
- Section 4.7.1.3 - added section on Pavement Preservation. Current Sections 4.7.1.3 to 5 became 4.7.1.4 to 6.
- Section 4.7.1.5 - minor edits
- Section 4.8.1.5 - added discussion of Earthwork Design
- Section 4.9.2.2 - Removed references to the NPS Value Based Decision-making document (could not be found on the web)
Chapter 5: SURVEYING AND MAPPING
The following changes are proposed:
- Changed FLH standard to include FGDC National Standard for Spatial Data Accuracy..
Chapter 6: GEOTECHNICAL
The following changes are proposed:
- Section 6.6 - Changed reference from FHWA-IF-99-025 to GEC-10, FHWA-NHI-00-043 to GEC-11, and FHWA-NHI-00-044 to FHWA-NHI-09-087.
Chapter 7: HYDROLOGY AND HYDRAULICS
The following changes are proposed:
- Removed refences to the "ohm-in" unit.
- Exhibit 7.1-A - Added section for Outlet Protection under ROADWAY HYDRAULICS. Moved Energy Dissipators section under RIVER HYDRAULICS
- Changed references to National Flood Frequency (NFF) to National Streamflow Statistics (NSS)
- Section 7.1.3.1.1 - added new section
- Section 7.2.1 - link to Terraserver USA removed. This site and its successor (MSR Maps) were both closed.
- Section 7.3.1.5.3 - rewrote section
- Section 7.3.2.4.3 - added erosion protection information
- Section 7.3.3.3.1 - Added criteria for roads with narrow shoulders
- Section 7.3.4.4.3 - rewrote section
- Section 7.3.5 - section reconfigured as Outlet Protection. Discussion on Energy Dissipators moved to Section 7.4.9.
- Exhibit 7.3-B - enlarged figure and made it dual units.
- Section 7.4.3 - changed the flood frequency and added additional information (including a new exhibit) on scour countermeasures.
- Section 7.4.6 - edits made to text
- Section 7.5.1 - section renamed and minor modifications to text
- Section 7.5.4.1 - modified section
Chapter 9: HIGHWAY DESIGN
The following changes are proposed:
- Minor changes throughout (unmarked)
- Used section numbers to refer to the 2011 Green Book
- Section 9.1.4 - Added section on variances to standard practice. Existing Section 9.1.4 became 9.1.5.
- Section 9.3.1 - Additional discussion on design controls, functional classification, local roads. Added a new Section 9.3.1.2.6 on special routes. Divided Section 9.3.1.9 into subsections with new content.
- Section 9.3.8 - Reformatted Section 9.3.8.4
- Section 9.3.14 - Added new Subsections 9.3.14.4.5 and 9.3.14.4.6
- Section 9.5.2 - Added Subsection 9.5.2.3.7
- Section 9.6.9 - Removed most of section and referred to other FLH documents.
Chapter 12: RIGHT OF WAY AND UTILITIES
The following changes are proposed:
- The FHWA Appraisal Guide no longer exists. References to the guide were removed from Sections 12.2.2, 12.8.4.2, and 12.8.4.4.
- The AASHTO Right of Way and Utilities Guidelines and Best Practices no longer exists. References to this document were removed from Sections 12.1.1.3, 12.2.2, and 12.3.