SIIMS Resources

Current Updates

• SIIMS Training SNBI Implementation
• 2023 ICEA Conference: Basics of SIIMS
• June 2023 SIIMS Update

Federal 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
  • Errata - June 2012
  • Errata - February 2018
• Input Procedures for FHWA Metrics

Underwater Inspection Procedures

• Wading Inspection Procedures
• Diving Inspection Procedures

BrR 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

• LRFD CIP Reinforced Concrete Box Culvert Program

LARS Input and File Upload Requirements

• LARS Input Spreadsheet
• LARS Consultant Requirements

Iowa 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