Local Bridges

LTAP works closely with the DOTD Bridge Inspection and Maintenance Section and the Bridge Design Section on issues related to local bridge management. Local agencies own and manage over 6, 000 bridges in Louisiana and account for 81% of the total number of public bridges in the state. The DOTD oversees compliance programs related to all bridges and assists local bridge owners in meeting federal requirements. LTAP is working with DOTD to inform and educate local bridge owners on new or expanded requirements affecting local bridge management and compliance with State and Federal standards.

LTAP is also working with DOTD to make resources available to enable local agencies to access materials necessary to implement and maintain local bridge management programs to ensure safety and meet compliance requirements.

For over thirty years the DOTD has assisted local bridge owners in meeting the requirements of bridge ownership by performing the required routine biannual compliance inspections on all bridges including the locally owned, off-system bridges and has submitted the results on behalf of the local bridge owners to the National Bridge Inventory (NBI) at FHWA. This has relieved local agencies of the need to maintain or contract certified bridge inspectors to meet the inspection requirements and ensured consistency across the state. However, local agencies have still been required to follow all other bridge program management requirements. Local bridge owners are required to:

• provide the initial load rating of all bridges
• conduct interim or special inspections of posted bridges
• maintain and repair bridges; follow closure requirements
• reevaluate load ratings of bridges when the conditions change and maintain adequate documentation.

In 2009 based on findings from the U.S. Office of the Inspector General, the Federal Highway Administration (FHWA) issued new oversight guidelines which passed into law and is known as the National Bridge Inspection Program Metrics. This law contains 23 specific metrics that are evaluated for full compliance. The FHWA evaluation of the 23 Metrics for Louisiana resulted in a finding of “conditionally compliant” which required the DOTD to develop and submit a Plan of Corrective Action with a goal of full compliance by December 2017. The failure of the state to achieve compliance will likely have serious consequences including increasing the liabilities of operating a bridge system network deemed to be not compliant with the federal inspection program.

The Louisiana Department of Transportation and Development (DOTD) is responsible for ensuring compliance with all federal requirements related to public bridges in Louisiana including the off-system bridges on locally owned roads. In Louisiana, the bridge owner is responsible for all aspects of bridge program management with the exception of the biannual compliance inspections, which DOTD conducts and documents. All interim inspections, maintenance and repair, initial load ratings, posting and closures, load rating reviews, file maintenance, etc., are the responsibility of the local bridge owner. Local bridge owners play a significant role in meeting the requirements of seven of the key metrics including Metric 11- Frequency Criteria, Metric 13- Load Rating; Metric 15 – Bridge Files; and Metric 20 – Quality Assurance/Quality Control (QA/QC), Metric 21 – Critical Findings, Metric 22 – Inventory Preparation and Maintenance, and Metric 23 – Timely Updating Inventory Data. The new rules as well as the previous one requires that the bridge owner conduct and report an initial bridge rating and to rerate a bridge in poor condition when the condition changes.

To ensure the safety of all bridges and to meet current federal regulations, the DOTD has identified bridges that lack sufficient load ratings and/or adequate files documenting the design, history and condition. The DOTD has begun an aggressive project to collect all available information on these bridges and to enforce the rating requirement. Action will be required by each local bridge owner. This may range from confirming ownership and verifying information on file to assembling missing file data and/or conducting load ratings. In addition, all bridge owners must attend a mandatory Bridge Program Management meeting which will be announced by each DOTD District Administrator. Technical assistance will be available to facilitate this important effort and if necessary a compliance schedule will be developed based on specific situations.

It is the responsibility of each bridge owner to provide an initial load rating for each bridge and to rerate bridges when the operating condition of a bridge warrants a rating change. The Louisiana DOTD is implementing an aggressive Compliance Program to ensure that all bridges in Louisiana are documented with verifiable load ratings. This class will provide an overview of the fundamental requirements of the bridge rating process required by DOTD and FHWA. Topics covered will include what is required by DOTD for rating documentation of each individual bridge, the purpose and benefit of load rating, explanations of the rating methods covered by AASHTO’s MBE including the preferred LRFR rating method, and policies and procedures associated with the methods for both new and existing bridges along with any unique rating loads currently utilized by our State. Examples of load rating procedures for common bridges in Louisiana will be presented. This class is an overview for experienced bridge rating engineers and bridge owners and does not replace the more extensive NHI Bridge Rating Class or other training programs.

This course provides novice and experienced bridge engineers with the fundamental knowledge necessary to apply the most recent AASHTO LRFR Specifications to bridge ratings and how the Louisiana DOTD rating requirements encompass these LRFR specifications. This course introduces participants to applications of LRFR specifications that can be used to enhance bridge safety and to identify and discuss the steps to ensure successful transition to this new state-of-the art methodology.