From the record
“The Douglas Crossing Bridge, near Granada, Colorado, was built in 1936 as a Works Progress Administration project. It was listed on the National Register of Historic Places in 1985.”
Wikipedia article Douglas Crossing Bridge, CC BY-SA 4.0.
One of 16 National Register listings published here for Prowers County · listed in 1985 · category: Structure · built in 1936.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service