S 21 over INT MIDWAY I 15


+48.13024, -111.90347
48°07'49" N, 111°54'12" W


Source: National Bridge Inventory. Information not verified; use at your own risk.
Name:S 21 over INT MIDWAY I 15
Structure number:P00021000+00001
Location:3M SE CONRAD
Purpose:Carries highway overpass over highway
Route classification:Minor Arterial (Rural) [06]
Length of largest span:105.6 ft. [32.2 m]
Total length:349.1 ft. [106.4 m]
Roadway width between curbs:43.6 ft. [13.3 m]
Deck width edge-to-edge:46.3 ft. [14.1 m]
Vertical clearance below bridge:16.4 ft. [5.0 m]
Skew angle:28°
Owner:State Highway Agency [01]
Year built:1972
Historic significance:Bridge is not eligible for the National Register of Historic Places [5]
Number of main spans:4
Main spans material:Steel continuous [4]
Main spans design:Stringer/Multi-beam or girder [02]
Deck type:Concrete Cast-in-Place [1]
Wearing surface:Monolithic Concrete (concurrently placed with structural deck) [1]

Latest Available Inspection: June 2017

Good/Fair/Poor Condition:Fair
Status:Open, no restriction [A]
Average daily traffic:562 [as of 2016]
Truck traffic:8% of total traffic
Deck condition:Fair [5 out of 9]
Superstructure condition:Good [7 out of 9]
Substructure condition:Good [7 out of 9]
Structural appraisal:Somewhat better than minimum adequacy to tolerate being left in place as is [5]
Deck geometry appraisal:Superior to present desirable criteria [9]
Underclearances appraisal:Equal to present minimum criteria [6]
Roadway alignment appraisal:Better than present minimum criteria [7]
Scour condition:Bridge not over waterway. [N]
Sufficiency rating:85.3

Previous Inspections

DateConditionDeckSuperstructureSubstructureADTSuff. Rating
June 2017FairFairGoodGood56285.3
June 2015FairFairGoodGood66099.0
July 2013FairSatisfactoryGoodGood660100.0
July 2011GoodGoodGoodGood660100.0
July 2009GoodGoodGoodGood640100.0
June 2007GoodGoodGoodGood930100.0
April 2005GoodGoodGoodGood760100.0
April 2003GoodGoodGoodGood900100.0
August 2001GoodGoodGoodGood90099.0
April 1999GoodGoodGoodGood920100.0
December 1996GoodGoodGoodGood1180100.0
November 1994GoodGoodGoodGood116098.0
October 1992GoodGoodGoodGood114098.0
January 1991GoodGoodGoodGood85098.0

Element Data

Source: National Bridge Elements dataset, 2019 edition. This feature is experimental.
Steel Girder/Beamlinear ft.2,0931,24883960
Steel Protective Coatingsq. ft.27,20914,9655,4422,7214,081
Reinforced Concrete Decksq. ft.16,11413,5909491,5750
Concrete Protective Coatingsq. ft.16,114005,58410,530
Reinforced Concrete Columneach99000
Reinforced Concrete Abutmentlinear ft.1381201530
Reinforced Concrete Pier Caplinear ft.157153400
Assembly without Seal Jointlinear ft.105396600
Movable Bearingeach24121200
Steel Protective Coatingsq. ft.2417025
Fixed Bearingeach66000
Steel Protective Coatingsq. ft.66000
Bridge Rail
Steel or Aluminum Bridge Raillinear ft.699069900
Steel Protective Coatingsq. ft.932187373186186