Office of Hydraulics and Stormwater Design

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Hydrualics and Stormwater Design

The Office of Hydraulics and Stormwater Design emphasizes stewardship of California's water resources by providing:

  • Development and maintenance of guidance and state-of-the-practice information for departmental staff to promote uniformity and consistency in the design of roadway drainage-related features.
  • Technical assistance to designers on unique or unusual drainage design issues.
  • Liaison to industry, Federal Highway Administration (FHWA), and other interested external entities for roadway drainage product approvals, processes, and requirements.
  • Technical assistance to designers on stormwater pollution control implementation.
  • Assistance to designers to assure compliance with Caltrans' statewide National Pollutant Discharge Elimination System (NPDES) permit.
  • Guidance and training for the implementation of appropriate Storm Water Best Management Practices (BMPs).
  • Management and performance of drainage related special studies and research activities.
  • Development and oversight of drainage-related training courses.
  • Development and maintenance of Roadway Drainage Standard Plans and Specifications.
  • Alternative Pipe Culvert Selection (AltPipe)
  • Approved Materials List
  • California Bank & Shore Rock Slope Protection Design
    • CALIFORNIA BANK AND SHORE ROCK SLOPE PROTECTION DESIGN - Practioner's Guide and Field Evaluations of Riprap Methods by James A. Racin, Thomas P. Hoover, and Catherine Crossett-Avila, report no. FHWA-CA-TL-95-10, 3rd Internet edition (October 2000)

      The above link above opens a file which includes the main report with text, tables, equations, and figures. The file is about 976 kilo-bytes and fits on a standard 1.44 M floppy disk. Chapter 5 of the report documents the California Bank and Shore (CaBS) layered rock slope protection (riprap) design method.

    • Update 1 Appendix A (April 2007)

      Update 1 replaces Appendix A of all 3 prior editions, and it is about 271 kilo-bytes. Three solved problems (CaBS layered RSP design method) were retained along with assumptions, dimensions, calculations, and figure references. The term “bankfull” was replaced with “full channel depth”. Problem-specific and generic figures were revised for clarification. Expressions and steps for changing the minimum dimensions of a MOUNDED Toe were revised. There is a discussion and general procedure for designing a granular filter using the Terzaghi design criteria. In problem 3 (concreted-RSP) terminology is consistent with the Caltrans Highway Design Manual. Figure A-9 was revised, and there is now an equation for estimating concrete volume. Based on 10 years of consultations with engineers in the public and private sectors, there are “Additional Topics” and figures. The “Additional Topics” are : Verifying Individual Rock Weights and RSP-Class, Guidelines for RSP Volume and Weight (with suggested values for porosity of revetments), RSP Toe (Scour and Embedded Depth, Mounded Toe, Bedrock), RSP Tolerance, Method A or Method B, Notes on ASTM Riprap Guide, and RSP (riprap) Monitoring. New Figure A-10 illustrates protruding and non-protruding revetments. New Figure A-11 has alternative dimensions which may be considered for a CaBS mounded toe. New Figure A-12 illustrates a stable toe design in bedrock.

      Field-evaluations are documented of riprap sites in five states : Washington, Oregon, California, Colorado, and Mississippi. Appendix C (Jan 2004) stands alone from the main report. There are 90 captioned color photo images with improved quality (300 dots per inch) as contrasted to prior editions. The captions describe design, construction, and maintenance issues of riprap and related features.

  • Gabion Mesh Corrosion
    • Gabion Mesh Corrosion - Field Study of Test Panels and Full-scale Facilities

      The second edition of the final research report, Gabion Mesh Corrosion Field Study of Test Panels and Full-scale Facilities (November 2001) was intended for distribution as a paperless report.

      All of the conclusions and all of the recommendations in both editions are identical. For general guidance see CONCLUSIONS (last paragraph of page 99, all of page 100), RECOMMENDATIONS (pages 101 through 105), and APPENDIX A (pages 110 and 126). Owners of the first edition (May 2001) should replace pages 16, 56, and 107. The cover, signature, and Technical Report Documentation pages were changed to reflect the November 2001 date. A few other pages have minor corrections. All of the photos were darkened to improve the images.

      Printed (hard-copy) reports are not available from Caltrans.

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Contact Information

Physical Address:

California Department of Transportation
Division of Design
1120 N Street
Sacramento, CA 95814

Mailing Address:

California Department of Transportation
Division of Design
MS 28
P. O. Box 942874
Sacramento, CA 94271-0001

General Information:

Design Liaison Phone List

Division of Design Org Chart

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