Construction Manual
This manual provides department construction engineering personnel instruction for fulfilling the objectives, procedures, and methods for construction administration of Washington State transportation projects. The Construction Manual is intended as a reference book.
The Construction Manual can be downloaded in PDF format and printed without charge.
Individual Chapters
Foreword (PDF 168KB)
Contents (PDF 220KB)
Chapter 1 Administration (PDF 1.3MB)
Chapter 2 Temporary Features (PDF 3.7MB)
Chapter 3 Earthwork (PDF 3.1MB)
Chapter 4 Aggregates and Bases (PDF 365KB)
Chapter 5 Surface Treatments and Pavements (PDF 553KB)
Chapter 6 Structures (PDF 4.4MB)
Chapter 7 Drainage Structures, Sewers, and Conduits (PDF 3.2MB)
Chapter 8 Miscellaneous Construction (PDF 2.7KB)
Chapter 9 Materials (PDF 1.7KB)
Chapter 10 Documentation (PDF 1.2KB)
Chapter 11 Forms (PDF 345KB)
Revision History
M 41-01.48
M 41-01.47
M 41-01.46
M 41-01.45
M 41-01.44
M 41-01.43
M 41-01.42
M 41-01.41
M 41-01.40
M 41-01.39
M 41-01.38
M 41-01.37
M 41-01.36
M 41-01.35
M 41-01.34
M 41-01.33
M 41-01.32
M 41-01.31
M 41-01.30
M 41-01.29
M 41-01.28
M 41-01.27
M 41-01.26
M 41-01.25
M 41-01.24
1,557 work zone-related crashes
were recorded on state highways in 2025.
542 people were injured
in 2025 due to work zone-related crashes.
29% increase in fatality collisions
in work zones from 2024 to 2025.