The Iowa DOT, often in cooperation with the Federal Highway Administration, works to identify and avoid historic properties as part of compliance with the National Historic Preservation Act (NHPA) of 1966 (as amended). This practice is often referred to as the Section 106 process.

Through Section 106 the Iowa DOT works with historic properties such as bridges, barns, archaeological sites, places of religious or cultural significance, historic cemeteries, and historic districts. Additionally, the Iowa DOT and the FHWA consult with various parties about historic properties.

The goal of Section 106 is to identify historic properties potentially affected by a project, assess potential impacts of the project and seek ways to avoid, minimize or mitigate any adverse effects on historic properties.

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Story Maps 

U.S. 30 Highway 30 Cedar River Bridge

U.S. 30 eastbound bridge over the Cedar River was completed in 1953 (FHWA #33470).  This bridge was evaluated as eligible for the National Register of Historic Places under Criterion C, representing the first of the welded I-girder bridges in Iowa.   This Story Map was created by Richard Carlson and Elizabeth Reetz in 2024.  View U.S. 30 Story Map.

A Sample of Historic Bridges in Iowa

Iowa is home to a number of historic bridges, and this Story Map shares details about five noteworthy structures.  This cross-section of historic bridges includes a variety of time periods, material types, construction styles and bridge engineers.  This Story Map celebrates some of Iowa’s most memorable bridges and was created by Maximilian Rolig in 2024.   View Historic Bridges in IA Story Map.    

Iowa’s Green Book Sites

From 1936-1966 the Green Book documented places that were safe for black motorists to stop at during the Jim Crow era. It included gas stations, restaurants, hotels, salons, and more.  This Story Map was completed as part of research to help understand what remains of Green Book properties in Iowa.  This Story Map was created by Madeline Shumaker in 2024.    

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Historic Bridges

Information and photographs of a wide range of historic bridges such as metal truss bridges, concrete arch and beam bridges, steel bridges, and the magnificent covered bridges of Madison County.

Learn more about Iowa's historic bridges

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Programmatic Agreement

The Iowa DOT, the Federal Highway Administration, the State Historic Preservation Officer and the Advisory Council on Historic Preservation have finalized their Programmatic Agreement that has established an updated process for compliance with the National Historic Preservation Act. This agreement was developed to establish an efficient and streamlined program for Section 106 compliance in Iowa.

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