DEARBORN RIVER BRIDGE, AUGUSTA, MONTANA

Below is an update provided by the HDR Engineering Company on efforts to preserve the Dearborn River High Bridge.

July 2, 2002

 RE:       Historic Bridge Identification Plates

Dearborn River Bridge 20 Km S. of Augusta, Control No. 3986

 The original bridge identification plates for the 1897 Dearborn River Bridge have been lost over the years.  We propose replacing these plates with replicas of the originals as part of the bridge rehabilitation and painting. Originally there was a plate on each of the four corners of the bridge. At each end of the bridge there were two plates, the manufacturers plate (The King Bridge Company), and a plate listing the Commissioners.  I am obtaining prices to see if it is feasible to replace these plates.

 There is documentation that shows what the plates looked like.  There is still a portion of the King Bridge Company plate on one end only. Pictures of similar plates and old catalogue pages showing details and dimensions may be found on the King Bridge Company’s website.  The original plate was 7 ¼” x 7 ¼”.

 The list of 1997 Commissioners plate was still on the bridge at one end only when we first inspected the bridge. That has since been stolen or lost.  We have a picture of that plate. The original plate appears to be about 11” x 9”.

 I have attached pictures of the Dearborn River Bridge plates and similar plates for information in producing replacement plates.  The original plates were cast iron. The replacement plates should probably be bronze with tamper resistant connections. The back side of the base plates are accessible for bolting.

 Please call if you have any questions.

 Respectfully yours,

 HDR Engineering, Inc.

 Bradley D. Miller, P.E.                                                                         

Senior Bridge Project Manager

Attachments

End View of Bridge showing 1897 List of Commissioners plate on left and King Bridge Co. plate on right.  The plates on the other end have been lost.  Since this picture was taken, the List of Commissioners plate has been stolen. 

List of Commissioners plate.  This plate has been stolen since this picture was taken.  About 11” x 9”

King Bridge Co. plate.  This is all that is left of this plate.  Information from the King Bridge Company’s web site reveals what this plate looked like.  7 ¼” x 7 ¼”,   Date on this plate should be 1897.

King Bridge Co. plate from another bridge.   This is what the plate for The Dearborn River Bridge should look like except that the date should be 1897.

King Bridge Co. page from old cataloge.   The bridge plate for this bridge is on the lower left of the page and shows the size as being 7 ¼” by 7 ¼” (note the scalloped corners).