National Bridge Inventory: Alaska



  • Of the 1,645 bridges in the state, 141, or 8.6 percent, are classified as structurally deficient. This means one of the key elements is in poor or worse condition.
  • This is from 141 bridges classified as structurally deficient in 2016.
  • The deck area of structurally deficient bridges accounts for 7.3 percent of total deck area on all structures.
  • 9 of the structurally deficient bridges are on the Interstate Highway System. A total of 85.8 percent of the structurally deficient bridges are not on the National Highway System, which includes the Interstate and other key roads linking major airports, ports, rail and truck terminals.
  • 150 bridges are posted for load, which may restrict the size and weight of vehicles crossing the structure.
  • The state has identified needed repairs on 301 bridges at an estimated cost of $272.1 million.
  • This compares to 287 bridges that needed work in 2016.

County Year Built Daily Crossings Type of Bridge Location
Ketchikan Gateway 1957 17,165 Urban minor arterial South Tongass Hwy over Hoadley Creek
Ketchikan Gateway 1955 14,046 Urban minor arterial South Tongass Hwy over Water St Viaduct
Fairbanks North Star 1953 7,264 Urban minor arterial Wendell Avenue over Chena River (Wendell)
Ketchikan Gateway 1975 6,725 Urban minor arterial North Tongass Hwy over Ward Creek
Anchorage 1966 5,535 Rural Interstate Seward Highway over Portage Creek No 1
Fairbanks North Star 1953 4,798 Urban minor arterial Minnie Street over Noyes Slough (Minnie St)
Anchorage 1967 4,276 Rural Interstate Seward Highway over Twenty mile River
Anchorage 1967 4,226 Rural Interstate Seward Highway over Placer River overflow
Anchorage 1966 4,226 Rural Interstate Seward Highway over Placer River Main Cross
Kenai Peninsula 1959 3,396 Rural arterial Sterling Highway over South Fork Anchor River
Fairbanks North Star 1960 3,097 Urban collector Aurora Drive over Noyes Slough (Aurora)
Matanuska-Susitna 1962 2,948 Rural Interstate Parks Highway over Sheep Creek
Kodiak Island 1980 2,871 Rural major collector Rezanof Drive over Sargent Creek
Kenai Peninsula 1965 2,042 Rural arterial Seward Highway over Snow River Cntr Channel
Kenai Peninsula 1965 2,042 Rural arterial Seward Highway over Snow River West Channel
Kodiak Island 1980 2,005 Rural major collector Chiniak Highway over Russian River
Yukon-Koyukuk 1958 1,799 Rural Interstate Parks Highway over Little Goldstream Ck
Matanuska-Susitna 1961 1,650 Rural Interstate Glenn Highway over Kings River
Kenai Peninsula 1949 1,603 Rural minor collector Old Sterling Hwy over Anchor River
Fairbanks North Star 1988 1,500 Urban local road River Road over Chena River
Not Available 1985 1,363 Rural major collector Craig/Klawock/Holl over Crab Creek Culvert
Not Available 1954 1,268 Rural major collector Copper River Hwy over Eyak River
Not Available 1974 952 Rural Interstate Richardson Highway over Gulkana River
Not Available 1980 947 Rural arterial Marine Hwy Route over Skagway Ferry Terminal
Not Available 1976 932 Rural major collector Gustavus Airport R over Salmon River
Type of Bridge Number of Bridges Area of All Bridges
(sq. meters)
Daily Crossings on All Bridges Number of Structurally Deficient Bridges Area of Structurally Deficient Bridges
(sq. meters)
Daily Crossings on Structurally Deficient Bridges
Rural Interstate 161 159,309 821,134 9 10,104 25,874
Rural arterial 104 60,895 131,078 5 3,563 8,612
Rural minor arterial 71 31,064 78,835 3 919 796
Rural major collector 216 118,566 120,574 18 9,491 9,941
Rural minor collector 108 34,299 30,058 11 2,352 4,004
Rural local road 718 99,371 32,616 71 12,603 2,275
Urban Interstate 40 34,567 860,643 0 0 0
Urban freeway/expressway 1 3,708 15,907 0 0 0
Urban other principal arterial 64 98,538 1,192,411 0 0 0
Urban minor arterial 45 66,313 370,762 5 10,494 49,998
Urban collector 47 26,868 101,004 6 1,840 5,189
Urban local road 70 21,191 36,069 13 3,029 2,711
Total 1,645 754,690 3,791,091 141 54,395 109,400
Type of Work Number of Bridges Cost to Repair
(in millions)
Daily Crossings Area of Bridges
(sq. meters)
Bridge replacement 63 $82 32,784 20,569
Widening & rehabilitation 1 $0 10,249 120
Rehabilitation 115 $127 105,729 48,463
Deck rehabilitation/replacement 0 $0 0 0
Other structural work 122 $62 10,332 20,273
Total 301 $272 159,094 89,425

About the data:

Data is from the Federal Highway Administration (FHWA) National Bridge Inventory (NBI), downloaded on March 11, 2021. Note that specific conditions on bridges may have changed as a result of recent work or updated inspections. Cost estimates were downloaded by ARTBA on March 11, 2021.

Effective January 1, 2018, FHWA changed the definition of structurally deficient as part of the final rule on highway and bridge performance measures, published May 20, 2017 pursuant to the 2012 federal aid highway bill Moving Ahead for Progress in the 21st Century Act (MAP-21). Two measures that were previously used to classify bridges as structurally deficient are no longer used. This includes bridges where the overall structural evaluation was rated in poor or worse condition, or where the adequacy of waterway openings was insufficient.

The new definition limits the classification to bridges where one of the key structural elements—the deck, superstructure, substructure or culverts, are rated in poor or worse condition. During inspection, the conditions of a variety of bridge elements are rated on a scale of 0 (failed condition) to 9 (excellent condition). A rating of 4 is considered “poor” condition.

Cost estimates have been derived by ARTBA, based on 2019 average bridge replacement costs for structures on and off the National Highway System, published by FHWA. Bridge rehabilitation costs are estimated to be 68 percent of replacement costs. A bridge is considered to need repair if the structure has identified repairs as part of the NBI, a repair cost estimate is supplied by the bridge owner or the bridge is classified as structurally deficient. Please note that for a few states, the number of bridges needing to be repaired can vary significantly from year to year, and reflects the data entered by the state.

Bridges are classified by FHWA into types based on the functional classification of the roadway on the bridge. Interstates comprise routes officially designated by the Secretary of Transportation. Other principal arterials serve major centers of urban areas or provide mobility through rural areas. Freeways and expressways have directional lanes generally separated by a physical barrier, and access/egress points generally limited to on- and off-ramps. Minor arterials serve smaller areas and are used for trips of moderate length. Collectors funnel traffic from local roads to the arterial network; major collectors have higher speed limits and traffic volumes and are longer in length and spaced at greater intervals, while minor collectors are shorter and provide service to smaller communities. Local roads do not carry through traffic and are intended for short distance travel.

16
Compared to 14 in 2019

in the nation in % of structurally deficient bridges

1. West Virginia 21.2%
15. Illinois 8.8%
16. Alaska 8.6%
17. New Hampshire 8.6%

45
Compared to 45 in 2019

in the nation in # of structurally deficient bridges

1. Iowa 4,571
44. Rhode Island 148
45. Alaska 141
46. Arizona 132

18
Compared to 19 in 2019

in the nation in % of structurally deficient bridge deck area

1. Rhode Island 21.0%
18. Alaska 7.0%
19. New Jersey 7.0%
Full State Ranking

Advertisement


  • Source: Data is from the Federal Highway Administration (FHWA) National Bridge Inventory (NBI), downloaded on March 11, 2021. Note that specific conditions on bridges may have changed as a result of recent work or updated inspections.

    ARTBA is a non-partisan federation whose primary goal is to aggressively grow and protect transportation infrastructure investment to meet the public and business demand for safe and efficient travel.

  • Privacy & Cookies Policy
Connect With Us

Copyright © 2021 American Road & Transportation Builders Association