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Current Updates
Back to topFederal Highway Administration (FHWA) Memoranda
- 1985 - Permits over 80,000 pounds allowed on Interstate highways
- 1993 - Requirements for using Load Factor Rating Method
- 2004 – Rating Method codes for NBI reporting
- 2006 – When can ASR vs. LFR vs. LRFR be used
- 2011 - Revisions to NBI items 31, 63, and 65
- 2011 – Revision to Rating Method codes for NBI reporting
National Bridge Inspection Standards (NBIS)
- Load Ratings for NBIS and SNBI Compliance
- NBIS Metrics
- NBIS 2005
- FHWA's FAQ on the NBIS
- Recording and Coding Guide for the Structure Inventory and Appraisal
- Input Procedures for FHWA Metrics
Underwater Inspection Procedures
Back to topBrR Iowa Standard Templates - Updated April 2025
- AASHTOWare Bridge Rating Training Material
- TR-832_Status on Template Completion
- Iowa DOT BrR System File Updates
- Iowa DOT BrR System and Library Data Summary_DRAFT
- BrR Templates
- Library and System Files
- Supporting Calcs
Load Ratings for Standard Bridges
- Iowa Load Rating Vehicles
- Phase 1 – 1982 ASR Rating Method
- Phase 2 – 1991 ASR Rating Method
- Phase 3 – 1998 ASR Rating Method
- Phase 4 – 2008 LFR Rating Method
- Phase 5 – 2016 LFR Rating Method
- Amendment to Phase 4 for SHV ratings
- Concrete Box Beam Standards
- Phase 6 - 2021 Load Rating for Standard Bridges
Load Ratings for Standard Culverts
- 2012 Cast in Place Culvert LRFR Ratings
- 2013 Single Precast RCB Std LRFR Ratings
- 2020 Cast in Place Culvert LRFR Ratings
- 2020 Single Precast RCB Std LRFR Ratings
Load Rating Tools for Concrete Box Culverts
Back to topLARS Input and File Upload Requirements
Back to topIowa DOT Maintenance and Inspection Manuals
- Bridge Inspection Manual
- Bridge Maintenance Manual
- Bridge Rating Manual
- Emergency Response Manual
- Bridge Rail Guide
Training Videos
- SNBI Training Video
- May 2023 SIIMS Webinar Recording
- May 2023 SIIMS Webinar Presentation
- Finding Structures
- Information Available in SIIMS for Structures
- Data Update Inspection Type
- Under Water Inspection Form
Other Information
- Listing of Bridge Inspection Agencies
- County and City Engineer's Form 107 Download
- Instructional Memorandum 7.020 Bridge Inspections