Scour & HydraulicsOnline self-study
Scour Critical Bridges and Plans of Action
1 PDH · about 60 minutes · Course no. BR-H02 · Instructor: Michael Craig, PE
About the instructor
Michael Craig, PE is Senior Vice President and Southeast Director at Strinteg Corporation, leading bridge inspection and structural engineering across eight states and Puerto Rico. In 27+ years he has inspected over 4,000 structures and completed 3,000+ load ratings and 160+ load tests. He has managed repair and preservation design for complex bridges, including cable-stayed bridges. He holds PE licenses in twelve states, DC and Puerto Rico, SPRAT Level 1, and FAA Part 107 credentials.
A bridge that is predicted to fail in a flood, or is already losing the soil under its foundations, cannot be left to the regular inspection cycle. This course explains what makes a bridge scour critical, how scour vulnerability is evaluated and coded, and how to write and maintain a Plan of Action (POA) that protects the public before, during and after floods. It draws on HEC-18, Evaluating Scour at Bridges, 5th Edition (FHWA-HIF-12-003, 2012), Chapter 10 and Appendix E; HEC-23, Bridge Scour and Stream Instability Countermeasures, 3rd Edition (FHWA-NHI-09-111, 2009), Chapters 1 through 3 and 9; the FHWA Recording and Coding Guide (FHWA-PD-96-001) Item 113 codes; and the current National Bridge Inspection Standards, 23 CFR 650.313(o). Section and table numbers are given so you can check each point. Scenario numbers that do not come from these documents are labeled illustrative.
⬇ Download study guide (PDF)
Learning objectives
- Define scour critical
- Describe evaluation methods
- Write a plan of action
- Monitor and close bridges
Outline
- Why scour critical bridges get special treatment
- Defining scour critical
- Item 113 codes and what they trigger
- Evaluation methods: screening, assessment and analysis
- Two kinds of observed risk: lessons from three failures
- The purpose and two core parts of a Plan of Action
- Management strategy: matching the response to the risk
- Inspection strategy and when to start monitoring
- Monitoring: visual, portable and fixed
- Closure, reopening and detours
- Countermeasure alternatives and the schedule
- The FHWA POA Standard Template
- Developing, implementing and maintaining the POA
- Bridges with unknown foundations
- Inspector duties and notification
- Worked scenario: writing a POA
- Summary
- Office review checklist before inspecting a scour critical bridge
- Open the course (24 screens, 2 knowledge checks)
- Final quiz — 10 questions, 70% to pass
References
- FHWA, HEC-23 Bridge Scour and Stream Instability Countermeasures, 3rd Edition, FHWA-NHI-09-111 and -112, 2009
- FHWA, HEC-18 Evaluating Scour at Bridges, 5th Edition, FHWA-HIF-12-003, 2012
- 23 CFR Part 650, Subpart C — National Bridge Inspection Standards (final rule published May 6, 2022)
- FHWA, Recording and Coding Guide for the Structure Inventory and Appraisal of the Nation's Bridges, FHWA-PD-96-001, December 1995, Item 113 – Scour Critical Bridges.
- FHWA Technical Advisory T5140.23, Evaluating Scour at Bridges, October 28, 1991 (as summarized in HEC-18 Sec. 10.6.1 and HEC-23 Sec. 2.1.1).
- FHWA Memorandum, Technical Guidance for Bridges over Waterways with Unknown Foundations, January 9, 2008 (as summarized in HEC-18 Appendix E).