By Cecilia Smith.
What are the items?
The BTAA Geoportal collates spatial layers from local and state agencies that cover a range of themes, including infrastructure. Among these layers are bridge datasets at the city, county, and state levels.
Browse the bridges of BTAA Counties
What BTAA Library submitted the item?
All 13 members of the BTAA Geoportal have submitted datasets of bridges in their states.
Interesting tidbits:
The types of data on bridges differ among states:
Some datasets, like Nebraska Bridges, include the date of bridge construction and reconstruction for all bridges in the state. The oldest listed bridge in the dataset was constructed in 1888.
IowaDOT provides individual feature layers for bridges proposed to replace the Black Hawk Bridge in Lansing, IA, including alternatives called the Purple Bridge, Blue Bridge, and Green Bridge.
Maryland’s Historic Highway Bridges contains historical bridges throughout the state. Images of the bridges can be viewed by clicking on a map pin in the geoportal and selecting the image URL in the table below the preview map.
Many of the datasets can be explored through your browser. For example, data hosted in ArcGIS Online lets users sort and filter the data based on criteria like date of construction, location, type, last inspection date, and more.
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| Caption: Historical image of the Black Hawk Bridge in Iowa that is slated to begin being replaced in 2024. The BTAA geoportal contains data for the proposed replacement and the original structure. |
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| Caption: Pocomoke City Bridge built in 1920 in Pocomoke City, Maryland. It’s a movable bridge with double-leaf bascules and a tender's house. Image urls are available in the dataset. |
Where can I find out more?
The BTAA Geoportal contains data on historical and contemporary bridges, in addition to scanned maps of bridge locations.
Users can use the Advance search function or the search facets to find bridge and infrastructure data for a given time period or location.
Have questions about this item, the BTAA geoportal, or maps and geospatial data in general? Please don’t hesitate to contact our project team!
Cecilia Smith is the GIS & Maps Librarian at the University of Chicago.