SR 520 over UNION BAY


+47.64500, -122.29745
47°38'42" N, 122°17'51" W


Source: National Bridge Inventory. Information not verified; use at your own risk.
Name:SR 520 over UNION BAY
Structure number:0006872A0000000
Location:0.4 E JCT SR 513
Purpose:Carries highway over waterway
Route classification:Principal Arterial - Other Freeways or Expressways (Urban) [12]
Length of largest span:100.1 ft. [30.5 m]
Total length:1902.0 ft. [579.7 m]
Roadway width between curbs:56.1 ft. [17.1 m]
Deck width edge-to-edge:63.0 ft. [19.2 m]
Owner:State Highway Agency [01]
Year built:1963
Historic significance:Bridge is not eligible for the National Register of Historic Places [5]
Design load:MS 18 / HS 20 [5]
Number of main spans:3
Main spans material:Steel [3]
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: August 2015

Good/Fair/Poor Condition:Fair
Status:Open, no restriction [A]
Average daily traffic:40,257 [as of 2012]
Truck traffic:4% of total traffic
Deck condition:Satisfactory [6 out of 9]
Superstructure condition:Satisfactory [6 out of 9]
Substructure condition:Satisfactory [6 out of 9]
Structural appraisal:Equal to present minimum criteria [6]
Deck geometry appraisal:Meets minimum tolerable limits to be left in place as is [4]
Water adequacy appraisal:Equal to present desirable criteria [8]
Roadway alignment appraisal:Equal to present desirable criteria [8]
Channel protection:Banks are protected or well vegetated. River control devices such as spur dikes and embankment protection are not required or are in a stable condition. [8]
Scour condition:Bridge foundations determined to be stable for the assessed or calculated scour condition. [8]
Operating rating:48.5 tons [44.1 metric tons]
Inventory rating:28.7 tons [26.1 metric tons]
Sufficiency rating:81.5

Previous Inspections

DateSuff. RatingConditionDeckSuperstructureSubstructureSD/FOADT
August 201581.5FairSatisfactorySatisfactorySatisfactory-40257
July 201386.7FairSatisfactorySatisfactorySatisfactory-40257
July 201183.6FairSatisfactorySatisfactorySatisfactory-70593
July 200982.9FairSatisfactorySatisfactoryGood-77871
July 200784.0FairSatisfactorySatisfactoryGood-77302
July 200583.0FairSatisfactorySatisfactoryGood-77302
December 200384.0FairSatisfactorySatisfactoryGood-77302
September 200184.0FairSatisfactorySatisfactoryGood-77302
July 199984.0FairSatisfactorySatisfactoryGood-77302
December 199784.0FairSatisfactorySatisfactoryGood-77302
November 199591.1FairSatisfactorySatisfactoryGood-77302
December 199491.1FairSatisfactoryGoodGood-77302
April 199286.7PoorPoorGoodGoodSD93250

Element Data

Source: National Bridge Elements dataset, 2016 edition. This feature is experimental.
ElementUnitsQuantity1. Good2. Fair3. Poor4. Serious
Steel Girder/Beamlinear ft.2,9002,900000
Steel Protective Coatingsq. ft.27,50013,47513,7500275
Prestressed Concrete Girder/Beamlinear ft.19,43419,429050
Reinforced Concrete Decksq. ft.134,471133,93952507
Reinforced Concrete Top Flangesq. ft.1,8881,64824000
Reinforced Concrete Pier Walllinear ft.7674020
Reinforced Concrete Abutmentlinear ft.133133000
Reinforced Concrete Pile Cap/Footinglinear ft.11000
Reinforced Concrete Pileeach8585000
Reinforced Concrete Pier Caplinear ft.1,3441,344000
Strip Seal Jointlinear ft.140014000
Compression Jointlinear ft.1,21008413690
Assembly without Seal Jointlinear ft.2100210
Elastomeric Bearingeach390385050
Movable Bearingeach2929000
Fixed Bearingeach2929000
Bridge Rail
Steel or Aluminum Bridge Raillinear ft.3,8043,7560048
Reinforced Concrete Bridge Raillinear ft.5,7065,698080
Reinforced Concrete Slabsq. ft.1,8881,888000