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Alaska Bridge Report
Alaska Department of Transportation and Public Facilities
November 2013
Alaska Department of Transportation and Public Facilities
2013
ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The Bridge Program and MAP-21 . . . . . . . . . . . . . . . . . . . . . . . . . 4 Funding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 New National Highway System Routes . . . . . . . 5 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Bridge Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Bridge Management System (PONTIS) . . . . . . . 7 StructurallyDeficientDeckArea . . . . . . . . . . . . . . 8 Performance Measures . . . . . . . . . . . . . . . . . . . . . . . 8
Bridge Program Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Scour Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 SeismicBridgeRetrofit . . . . . . . . . . . . . . . . . . . . . . . 10 Functionally Obsolete and Fracture-Critical Bridges . . . . . . . . . . . . . . . . . . . . . . . 11 Bridge Closing and Load Posting . . . . . . . . . . . . . 12 Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Preservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Rehabilitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 BridgeAgeandConstructionMaterials . . . . . . . 14
Project Programming and Planning . . . . . . . . . . . . . . . . . . . . . . 15 Schedule of Improvements . . . . . . . . . . . . . . . . . . . . 15 STIP Funding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
The Alaska Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Natural Resource Development . . . . . . . . . . . . . . . 17 Environmental Factors . . . . . . . . . . . . . . . . . . . . . . . . 17 LackofReduncancyintheHighwaySystem . . 17 Specialized Structures . . . . . . . . . . . . . . . . . . . . . . . . 18 Short Inspection Season . . . . . . . . . . . . . . . . . . . . . . 18
Closing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 AppendixA:GlossaryofTerms . . . . . . . . . . . . . . . . 21
AppendixB:StructurallyDeficientDOT and other Public Bridges . . . . . . . . . . . . . . . . . . . . . . 23
AppendixC:StructurallyDeficientBridges IdentifiedforReplacementinthe2012-2015 Statewide Transportation Improvement Plan (STIP) . . . . . . . . . . . . . . . . . . . . . . 26
AppendixD:LocationofBridges SeismicallyRetrofitted . . . . . . . . . . . . . . . . . . . . . . . . 28
AppendixE:NationalHighway SystemRoutesinAlaska . . . . . . . . . . . . . . . . . . . . . 29
The Cold Bay ferry ramp, one of the many specialized structures maintained by the Department of Transportation and Public Facilities. See page 18. Photo by Peter Metcalfe .
Kasilof River Bridge 150 miles south of Anchorage on the Sterling Highway. Photo by Kathleen Metcalfe .
AlaskaDepartmentofTransportation&PublicFacilities|3
TheAlaskaDepartmentof
Transportation and Public
Facilities is responsible for
inspecting 996 bridges on public
roadsinAlaska,1 including 810
bridgesownedbythedepartment,
23 owned by other state agen-
cies,and163ownedbycitiesand
boroughs . These inspections are
subject to the requirements estab-
lishedbytheFederalHighwayAd-
ministration.TheAlaskaRailroad
Corporation is responsible for the
inspection of most bridges on the
railsystem,whilefederalagencies
inspect the bridges under their
jurisdiction .
This report addresses all bridges
for which the department has in-
spectionresponsibility,butfocus-
es on the 810 bridges owned and
operated by the department .
The department’s bridge inventory
includes 77 culverts twenty feet
orgreaterindiameter,ninedrive-
downrampstoseaplanefloats,
and35rampsatAlaskaMarine
HighwaySystemterminals.Allof
thesestructuresareintheFHWA’s
National Bridge Inventory System
(NBIS),althoughonlyroadand
highway bridges are the subject
of this report . Federal legislation
(MAP-21,seebelow)hasadded
four tunnels to the inventory .
Drive-down ramps at small boat
harbors are not counted .
Department engineers annually in-
spect about 500 bridges on public
roads to identify problems and en-
gageinacorrectiveworkprogram
thatassuresAlaskabridgesare
safe and in overall good condition .
Bridge inspection and remediation
Introduction
1 Federally-ownedbridgesareexcludedfromalldatainthisreport.PleaserefertotheGlossaryinAppendixAforthedefinitionsoftechnicalandengineeringterms.
is ongoing and will always face
challenges.Aboutone-thirdofthe
bridges in the state are past the
mid-point of their 75-year design
life — the design life for bridges
builtafter1995.Beforethen,bridg-
es were designed for a 50-year
designlife.Industrialactivities,in-
cluding mining and oil or gas field
development and future construc-
tionofoilornaturalgaspipelines,
may require rehabilitation and/or
replacementofexistingbridgesto
carry the significant traffic loads
such development generates . Pop-
ulationgrowth,increasedtraffic
volumes,andenvironmentalfac-
tors such as high runoff volumes
and thawing permafrost also place
demands on the bridge inventory .
Bridge Ownership
Other State Agencies
23
Local
163
AlaskaDepartmentofTransportation&
Public Facilities
810
The listing of structurally deficient bridges in Appen-dix ‘B’ of the report is based on bridge inspections per-formed by the department in 2012. The list is used to cal-culate structurally deficient deck area (see graph on page 8), and represents the most ”real time” account-ing of structurally deficient bridges, but is unofficial, since the list has not been formally approved by the FHWA for inclusion in the National Bridge Inventory.
4|2013AlaskaBridgeReport
MAP-21representsanewdirec-tion in surface transporta-tion and bridge funding . The
authorization eliminates the Highway BridgeProgram,butincludesbridgeeligibility in the Surface Transporta-tion Program and (new) National Highway Performance Program (NHPP)categories,andaddstun-nels to each state’s bridge inventory . Thelegislationalsomodifiesbridgeinspection standards and requires theFHWA,withinputfromthestates,to establish performance measures for bridges on the National Highway System (NHS) .
MAP-21focusesonNHSroutes,including NHS bridges and tunnels.Essentially,MAP-21
createsthreeclassesofbridges:
• NHS bridges funded through the National Highway Perfor-mance Program;
• non-NHSbridges,amixofstate and local bridges on major collectors and minor arterials; and
• off-systembridges,oftenowned by cities or boroughs on local roads and minor col-lectors .
FundingBridge funding in the (now) su-persededhighwayauthorization,SAFETEA-LU,occurredunderadis-creteprogram,theHighwayBridgeProgram.AlthoughthisprogramisdiscontinuedunderMAP-21,fundingforbridgeandtunnelpreservation,rehabilitation,andconstructionisavailable under the Surface Trans-portation Program (STP) and the
The Bridge Program and MAP-21In July of 2012 the U.S. Congress passed a surface transportation authorization bill, MAP-21, or “Moving Ahead for Progress In the 21st Century.” The legislation took effect on October 1, 2012.
National Highway Performance Pro-gram (NHPP) . The Highway Safety Improvement Program (HSIP) may alsobeusedforbridgeworkcon-sistent with the Strategic Highway SafetyPlanortoresolveaknownhazard or safety issue .
Only bridges and tunnels on Nation-al Highway System (NHS) routes may be funded through NHPP . By federalrequirement,atleast15%ofthe state’s STP allocation must be setasideforoff-systembridges,typically bridges on roads function-allyclassifiedasminorcollectorsorruralroads,oftenownedbylocalgovernment (the set-aside can-notbelessthan15%oftheState’sFY2009 Highway Bridge Program apportionment — about $4 mil-lionthisfiscalyear).Fundingforallotherbridges,the400-plusthatareneitheroff-systemnoronthe
Asset management is a systematic process of operating, maintaining, and improving physical assets by focusing on engineer-ing and life-cycle economic analysis based on up-to-date, standardized informa-tion. The department recog-nizes Transportation Asset Management as a valuable approach to preserving assets at a time of grow-ing demand and shrinking resources.
Bridge ConditionsAllStateandLocalBridges
FAIR
46%
GOOD
43%POOR
11%
AlaskaDepartmentofTransportation&PublicFacilities|5
NHS,isavailableundertheSurfaceTransportation Program . One-half of theSTPallocation,afterset-asidesforoff-systembridges,transporta-tionalternatives,andplanningandresearch,isallocatedbypopulation,whiletheremaining50%isavailablefor projects in any area of the state .
MAP-21isfocusedonpreservationof the National Highway System . The legislation includes penalties for failing to adequately maintain NHSbridges,thushelpingassureadequate bridge funding on the state’sprincipalroutes.Off-systembridges receive annual funding throughaset-asideformula,how-ever,theminimumfundinglevelof$4millionisapproximately18%less than the average funding level between2006and2011.Allotherbridges that are eligible for federal funding must compete against all other projects for available funds in the Surface Transportation Program allocation . The available level of federal funding is not considered sufficienttofullyaddressAlaska’sknownbridgeconditions.(Seethesection on Project Programming and Planning on page 15 for additional detail on programming and funding .)
New NHS RoutesMAP-21expandedtheNationalHighway System to include all urban and rural principal arteri-alsandotherconnectorhighways,andallStrategicHighwayNetwork(STRAHNET)routesandconnec-tors.InAlaskathistotaledalittleover77centerline-miles,withmostinAnchorage(52.58miles)andtheMat-SuValley(22.10),andtheremainderinFairbanks(1.43miles),Haines(0.67miles),Juneau(0.38miles) and the Kenai Peninsula (0 .10 miles).TwelveAlaskabridgeswereaddedtotheNHSsystem,mostofthem(nine)inAnchorage.(AmapofmajorNHSroutesinAlaskaisinAppendixF.)
InspectionMAP-21continuestorequirea24-monthbridgeinspectioncycle,and department inspectors will continue to use condition ratings andsufficiencyratingstoidentifycandidate bridges for rehabilitation andreconstruction;however,thesufficiencyratingwillnolongeractas a ‘trigger’ for bridge rehabilita-tion and reconstruction funding . In place of the former evaluation of the bridgedeck(thedrivingsurface),the substructure (elements such as abutments and piers) and the super-structure(elementssuchasgirders),onwhichsufficiencyratingshavebeenbased,theFHWAnowrequiresanelement-levelinspection;thatis,each separate element of the bridge must be inspected and rated .
Elementswillvarybybridgetype,but include primary elements such asdecks,slabs,girders,pilings,col-umns,andabutments,andsecond-aryelementssuchasjoints,bear-ings,railsandprotectivesurfaces.Bridge engineers collect element-leveldatanow;however,thisnewuniversal requirement will increase
bridgeinspectiontimes,andtheaccurate entry of considerably more datasets into PONTIS will be time-consuming .
MAP-21requirestheFHWAtoes-tablish performance measures for bridges on the National Highway System within eighteen months of enactment,orbyApril1,2014.Thelegislation also sets a minimum threshold for bridge condition on the NHS by requiring that no more than10%oftotalNHSbridgedeckareamaybeonstructurallydeficientNHSbridges,averagedoverthreeconsecutiveyears.Initialexamina-tion indicates that for the last three years(2010-2012),thepercentageoftotaldeckareaofNHSbridgesonstructurallydeficientbridgeshasaveragedjustinexcessof10%.Forthe past four years (2009-2012) it hasaveragedjustbelow10%.
MAP-21makestunnelinspectionsa state DOT responsibility . Few tunnelsexistonthestate’shighwaysystem,inKetchikanonTongassAvenueandbeneaththeKetchikan
Culverts for the Marshall Airport Access Road. PhotobyClydeKelso,ADOT&PF.
6|2013AlaskaBridgeReport
airportrunway,andontheSewardHighwayatPortage.TheAntonAn-dersonMemorialTunnel(ie,‘Whit-tierTunnel’),thelongestcombinedvehicle-railroad tunnel in North America,isinspectedbythedepart-ment on both a daily and a monthly basis,andfollowingearthquakesorothergeologicactivity.AlaskaRailroadpersonnelinspectthetrackstructuretwiceweekly.Thetunnelis also under constant view via a department CCTV system .
Regular inspection of the state’s bridges provide up-to-date infor-
mationontheirphysicalcondition,ensurespublicsafety,andprovidesa factual basis for public investment inbridgepreservation,replacement,and rehabilitation . Federal regula-tions mandate bridge inspections on a 24-month interval for the above-water,accessibleportionsofthebridge,andona60-monthrota-tion for the portions of bridges that are continuously underwater .
The state’s bridge inspection pro-gram complies with the National Bridge Inspection standards to as-sure high quality standards . Bridge
inspections can range from routine toin-depth,dependingonabridge’sindividual characteristics and needs . The inspection by bridge design engineers gives the design group valuable information on bridge conditionsandperformance,“wearandtear,”andotherfactors.Mostin-spection team leaders are licensed professional engineers with at least fiveyearsofbridgedesignandin-spectionexperience.
Engineers may inspect smaller bridgesonfoot,whilesomestruc-tures require the use of a special under-bridge-inspection vehicle with ajointedarmandbucket,orplat-form,whichallowsaccesstooth-erwise inaccessible locations . The timeittakestoinspectabridgecanvary from an hour to several days depending on the length and width ofthespan,weatherconditions,andlocation on the road system .
MAP-21requirestheestablishmentofanationalcertificationforbridgeand tunnel inspectors . The Secre-tary of Transportation is required to prepare an update on inspec-tion standards that will include the methodology,training,andqualifica-tionsforinspectors.Workingwiththestates,theSecretarywillalsomaintain a program to train bridge andtunnelinspectors,andrevisetheprogramperiodicallytoreflectnew and improved techniques .
Bridge RatingBridge inspectors continue to collect data for a Condition Rating and a SufficiencyRatingasinthepast,whiletheFHWApreparesrevisedrating standards for bridges and tunnels based on element-level inspection data . Each state Depart-mentofTransportationisrequired,within two years of enactment of MAP-21,orbyOctober1,2014,toreport element-level data on bridges ontheNHS.Alaskabridgeinspec-
Percentage of Total Deck Area of NHS Bridges on Structurally Deficient Bridges 2009-2012
20090
2
4
6
8
10
Perce
ntStructurally
Defi
cien
tDec
kA
rea
2010 2011 2012
8 .2
9%
11 .4
5%
9 .7
5%
10 .0
%
Juneau-Douglas Bridge Roundabout. Photo by MalMenzies,ADOT&PF.
AlaskaDepartmentofTransportation&PublicFacilities|7
tors already collect bridge condition dataattheelementlevel,andwithmodificationstoPONTIS2,thebridgesection’sassetmanagementsystem,inspectors will be prepared to enter and report element-level data by the 2014 deadline .
Department engineers classify the conditionofAlaskabridgesusingnu-mericalrankings(7-9=good;5-6=fair;0-4=poor),Bridgesinthegood-condition category may have minor problems that can be addressed with preservation or maintenance prac-tices . Bridges in the fair-condition categoryarestructurallysound,butshowminordeterioration,crack-ing,spalling,orscourthatcanbecorrected through repair . Bridges in the poor-condition category show advanceddeterioration,maynotbestructurally sound and are candi-dates for rehabilitation or replace-ment and may require weight or lane restrictions . (See more about weight and lane restrictions on Page 12 and inAppendixB.)
TheFHWAhasusedtheRecording and Coding Guide for the Structure Inventory and Appraisal of the Na-tion’s Bridges to identify the data entered into the National Bridge
Inventory . The guide is currently beingrevised,aneffortthatcouldtakeuntil2014orlater.BecauseMAP-21requireselement-leveldatatobecollectedandsubmitted,itseemsreasonabletoexpectthattheemerging element-level data col-lection requirements would replace orsupplementtheexisting‘condi-tionrating’and‘sufficiencyrating’requirementsinarevisedGuide.
Bridge Management System (PONTIS)PONTIS is a software program that stores and analyzes data collected on the condition of bridge elements
includingthedeck,beams,piers,railings,trusses,andotherfeatures.Atpresent,PONTISmainlyhousesdata,althoughithasthepotentialtosupport the department’s emerging commitmenttoassetmanagement,and aid in meeting federal perfor-mance standards for the element-levelinspectionofbridgeseffectiveonApril1,2014.
PONTIS stores complete bridge inventoryandinspectiondata,including detailed conditions of bridge elements . It can help iden-tify system-wide preservation and improvement strategies for use in evaluating the needs of all bridges in the system . It has the capability to recommend projects that would derivemaximumbenefitfromavail-ablefunds,reportonsystem-wideandproject-levelresults,andfore-cast system-wide life-cycle costs . PONTIS elements currently focus on maintenance-related condition inspections,butpendingchangeswill place a larger emphasis on structural features and safety .
Full utilization of PONTIS should enablethedepartmenttomakesound,defensible,andrepeatableinvestment decisions for bridges in the department’s inventory . It will support a preservation approach by identifyingacost-effectivestrategyfor preserving the overall bridge
2“PONTIS”isLatinfor“bridge.”
The Fred Zharoff Memorial Bridge in Kodiak. Photo by Peter Metcalfe .
Barnett Street Bridge in Fairbanks. PhotobyMeadowBailey,ADOT&PF.
8|2013AlaskaBridgeReport
system and quantifying the costs of deferringneededmaintenance,repair,and rehabilitation activities . PONTIS softwareiscurrentlybeingmodifiedtomakefulluseofelement-levelinspec-tiondataasrequiredinMAP-21.
Structurally Deficient Deck AreaMAP-21identifiesthedeckareaofstructurallydeficientbridgesontheNational Highway System as an important performance measure . The department annually calculates the deckareaofstructurallydeficientbridges . In the ten-year period be-tween2003and2012,thetotaldeckarea square footage of structurally deficientDOTbridgesdecreasedbyalittleover25%,from844,000squarefeetto572,200squarefeet.
Althoughtrendingdownwardoveraten-yearperiod,thedeckareasquarefootageofstructurallydeficientDOT bridges has risen from a low of 415,000squarefeetin2008tothe2012figureof572,200squarefeet,an increase of about one-third . This is due to a net increase in the num-ber of bridges being designated as structurallydeficienteachyearthanare being rehabilitated or replaced . Forexample,2012bridgeinspec-tions removed nine bridges from thestructurallydeficientbridgelist,
however,fourteenbridgeswereaddedto the list for 2012 . The 96 structur-allydeficientDOTandotherpublicbridges listed in this report comprise atotaldeckareasquarefootageof664,500squarefeet.Just7ofthesebridges,or7.3%,comprise44%ofthetotaldeckareaofstructurallydeficientbridges.Thisindicatesthatthe addition or deletion of just a few structurallydeficientbridgescanhaveasignificanteffectonthetotalnum-bers .
The square footage of structurally deficientdeckareainthereporthasbeen calculated for DOT-owned bridges,andforotherlocalandstatebridges inspected by DOT . Structur-allydeficientdeckareahasalsobeencalculatedforNHS,non-NHS,andoff-systembridges,consistentwiththefundingtemplatecreatedinMAP-21.
Thethirty-eightstructurallydeficienthighway bridges on the NHS com-prise395,000squarefeet;thenine-teenstructurallydeficientnon-NHShighwaybridgescomprise119,800square feet; and the thirty-nine struc-turallydeficientoff-systemhighwaybridgescomprise149,700squarefeet.Structurallydeficienthighwaybridgesthat are closed are not included in these counts . The recent increases in structurallydeficientdeckareasquare
footage,combinedwithMAP-21’sfocusontheNHS,putnon-NHSandOff-Sys-tembridgesatafundingdisadvantage,and raise concerns over the long-term maintenance,rehabilitation,andre-placement of these bridges without additional sources of funding .
Thirty-fourstructurallydeficientbridges are scheduled in the 2012-2015 STIP for replacement or rehabili-tation.Structurallydeficientdeckareacanchangesignificantlyfromyeartoyear . But as bridges are rehabilitated orreplaced,otherbridgeswillcontinueto deteriorate with age . The amount of structurallydeficientdeckareawillfluc-tuateeachyear,butwiththeapplicationofassetmanagementprinciples,thattotalisexpectedtotrenddownward.
Performance MeasuresTheSecretaryofTransportation,inconsultationwiththestates,mustestablish performance measures for bridges on the National Highway SystembyApril1,2014.WithinayearfollowingfederalDOT’sfinalruleonperformancemeasures,orbyApril1,2015,ADOT&PFmustsetperformancetargets to support those measures for AlaskabridgesontheNHS.Itislikelytheseperformancetargets,orarelatedsetofstandards,willbedevelopedforother federal aid-eligible bridges not on theNHS,andforOffSystembridges.
Deck Area of Structurally Deficient BridgesDOT,LocalandOtherStateBridges
2003-2012
2003
DOTBridges&LinearTrend DOTBridges&LinearTrend2008-2012
Local&OtherPublicBridges&LinearTrend
2004 2005 2006 2007 2008 2009 2010 2011 2012
200,000
0
400,000
600,000
800,000
AlaskaDepartmentofTransportation&PublicFacilities|9
Dowling Street bridge in Anchorage. Photo by Kathleen Metcalfe .
10|2013AlaskaBridgeReport
Scour Monitoring“Scour”istheengineeringtermfortheerosionofstreambedorbankmaterialduetoflowingwater.Themost common cause of bridge fail-uresisfromfloodsscouringstream-bed material from around bridge foundations (piers and abutments) . Bridges that are vulnerable to scour aretermed“scour-critical.”
National Bridge Inspection Stan-dards (23 CFR 650) require states to identify scour-critical bridges and their owners to prepare a Plan ofAction(POA)tomonitorscourconditions and to address potential deficienciesandcriticalfindings.Bridge scour countermeasures may includemorefrequentinspections,installation of active monitoring sys-tems,andstructuralimprovementssuch as riprap to resist scour .
Thedepartmenthasidentified110“scour-critical”bridgesin2012,including 20 bridges owned by local governments,11bridgesownedbytheAlaskaDepartmentofNaturalResources,and79bridgesownedbythedepartment.In2012,theFHWAsought greater involvement by the department in the management of non-DOT&PFpublicbridges.Conse-quently,in2012andearly2013the
Bridge Program Features
Scour Program applied arisk-basedscreeningtooltoallnon-DOT&PFpublicbridges,develop-ingandprovidingPOAtemplates for non-DOT&PFbridgeownersto facilitate scour moni-toringandriskmanage-ment activities .
Department bridge inspectorsmakeassess-ments of scour-critical bridges annually rather than the 24-month cycle used for routine bridge inspections . Additionally,seventeenofthesebridgesfeatureremote(i.e.,electron-ic) scour monitoring systems that provide near real-time scour data at the bridge pier(s) . The department also collaborates with other agen-cies,notablytheU.S.GeologicalSur-vey,toconductcomplexscourandbridge hydraulics studies at selected bridges .
The 2012-2015 STIP has pro-grammed$2,850,000overthreeyears to sustain the Bridge Scour Monitoring program .
Seismic Bridge RetrofitAlaskaisthemost seismically active state in the union . The de-partment imple-mented a seismic retrofitprogramforAlaskabridg-esin1995,usingseismic hazard data from the U.S.GeologicalSurvey.Thisdata,together with a
seismic vulnerability assessment of Alaskabridgesandadeterminationofpriorityhighwayroutes,hasre-sulted in the prioritization of bridges forseismicretrofit.
Consistent with national standards adoptedbytheAmericanAssocia-tion of State Highway Transporta-tionOfficials(AASHTO)andtheFHWA,thedepartmentretrofitsbridges in an attempt to prevent collapseduringanearthquake.Public safety is the foremost con-sideration . The department designs newbridgestothe“nocollapse”standard contained in the current AASHTOspecifications.
The department has adopted a two-phaseseismicretrofitpro-gram . Phase One of the program addresses the most critical bridge deficienciesthatcanbeaccom-plishedfortheleastcost.Typically,thedepartmentcanretrofitaboutten bridges annually with a budget ofapproximately$2.4million.PhaseOneretrofitsimproveabridge’santicipated seismic performance but do not necessarily bring the bridge into compliance with current “nocollapse”standards.TheintentofPhaseOneistoretrofitasmanybridges as is economically feasible
A popular boat launch ramp next to the Kenai River Bridge. Photo by Kathleen Metcalfe .
Placing a 300 lb. depth and current monitor in the Copper River.PhotobyMikeKnapp,ADOT&PF.
AlaskaDepartmentofTransportation&PublicFacilities|11
with the available funds .
Phase2oftheretrofitprogramisintended to address vulnerabilities in the bridge columns and founda-tions.Thesedeficienciesaretypical-lymuchmoreexpensivetocorrect,resultinginfewerPhase2retrofitsfor the same amount of funds . The department has addressed many Phase 1 priorities and has com-pleted Phase 2-type improvements onbridgesinKodiakandSitka,andmorerecently,theSusitnaRiverBridge.SixadditionalPhase2retrofitsareindesign,includingthe Nenana River Bridge at Moody . Phase1workwillnotcease,butoverall priorities may shift toward Phase2work,particularlyforcriticalbridgelinksontheNationalHigh-waySystem.(SeeAppendixEforthelocation of bridges seismically ret-rofittedbetween1996and2013,andthe location of Richter Scale 6 .0 and greaterearthquakessince1965.)
The 2012-2015 STIP has pro-grammed$6,000,000overthreeyears to implement the Seismic BridgeRetrofitprogram.
Functionally Obsolete and Fracture-Critical BridgesThe recent bridge collapse on Interstate5nearMt.Vernon,Washington,hasfocusedattention again on bridge safety . This report has addressed structural deficiency.Twoadditionalbridgetermsthatevokepublic concern over safety need to be addressed as well:‘fracture-critical’and‘functionally obsolete .’
Afunctionally obsolete bridge is one that does not meet current design standards . It can be com-pletelysafetouse,butmay have narrower lane
widths,smallershoulders,lowerver-ticalclearance,reducedloadcapac-ity,orotherfeaturesthatweresuit-ableatthetimeofconstruction,butare inconsistent with current design requirementsandtrafficdemands.
Bridges conform to the design stan-dards in place at the time they are constructed.Thedegreeofdiffer-
The Old Knik River Bridge. PhotobyRonMartindale,ADOT&PF.
Strengthening a pier on the Nenana River Bridge. PhotobyElmerMarx,ADOT$PF
12|2013AlaskaBridgeReport
ence between current design stan-dards and those in place for a bridge constructedatapriortime,deter-mines whether a bridge receives a functionallyobsoleteclassification.Dependingontheyear,about10%ofthe DOT bridge inventory is typically classifiedasfunctionallyobsolete,consistent with percentages nation-wide.In2012,seventy-fivehighwaybridgesinAlaskawereclassifiedasfunctionally obsolete .
Afracture-critical bridge is a bridge
that does not con-tain redundant sup-portingelements:ifakeysteelelementfails,thebridgeisin danger of col-lapse . To be termed fracture-critical,theelement must be intension,withnoother element (or system of elements) that can provide back-upincaseoffailure.Inshort,thismeans that there is no means of trans-ferring the weight being supported by that element to hold upthebridge,andifitfails,collapsecan
occurquickly.TheFHWAclassifiesabout18,000bridgesnationallyasfracture-critical.Seventy-sixhigh-way bridges owned or inspected by thedepartmentwereclassifiedasfracture-critical in 2012 .
Abridgecanbefunctionallyobsolete,fracture-critical,orboth,andbesafeforvehicletraffic.Whenpublicsafetyisatrisk,thedepartmentload-postsbridges,orclosesthemtotraffic.
Bridge Closing and Load PostingAlaskatrafficvolumesarelowbynationalstandards,makingtraffic-generated deterioration a less significantfactorinAlaskathaninotherstates.AdditionalfactorsaffectingAlaskabridgesincludeage,rotandrelateddeteriorationoftimberbridges,scour,overweightloads,andenvironmentaldamagefromcorrosionandtheeffectsof freeze-thaw cycles . Vehicle collisions can also result in structural damage .
Abridgeclosureorpostingofre-duced load capacity typically occurs when advanced deterioration or im-pact damage reduces structural ca-pacity below state legal loads . Some bridges designed under old codes andstandardsforsmallertruck-loads,mayalsorequireloadposting.Regular inspections typically spot problems in time for implementa-tionofcorrectivemeasures,makingclosure a last option .
Currently,eightbridgesclassifiedasstructurallydeficientareclosedtotraffic.Anadditionaltwenty-ninebridgesclassifiedasstructurallyde-ficienthavepostedloadand/orlane(i.e.,one-waytraffic)restrictions.Three load-posted bridges were replaced in 2012 and 2013 at Falls Creek,PtarmiganCreek,andTrailRiver,allontheNHS.Almostallofthe remaining restricted bridges are on low-volume rural or local routes .
2012 Deck Area Square Footage of Structurally Deficient Bridges
Bridges:DOTandOtherPublicBridges
NHS
DOT Other Public
Non-NHS Off-System
390,00 sq .ft .
5,043 sq .ft .119
,800 sq .ft .
047,900 sq .ft .
101,800 sq .ft .
Removing the deck of the Peterson Creek Bridge. PhotobyMichaelKell,ADOT&PF.
Steve Banse inspecting the Swanson River Bridge. PhotobyLarryMiller,ADOT&PF.
AlaskaDepartmentofTransportation&PublicFacilities|13
DesignDesign,asacomponentofbridgepreservation,accountsforenviron-mentalconditions,trafficvolumes,vehicleweight,andotherfactors,and helps to assure longer bridge life,greatereaseofroutinemain-tenance,andgreatersafety.Thedepartment is currently preparing a bridge manual that emphasizes design as a means of assuring bridge safety and service life . The new manual will address virtually every stage of a bridge’s life includ-ingplanning,design,constructionsupport,inspection,rating,andrehabilitation .
PreservationPro-active preservation by the departmentkeepsbridgessafeandoperational.Preservationextendsbridge service life and forestalls the needformorecorrective,reactivemaintenance,andincludesactivitiessuchaspainting,cleaningjointstopreventdeteriorationand/orfailure,and sealing surfaces to prevent water penetration .
Continuing implementation of asset management practices based on data entered in the department’s bridge management system (see PONTIS above) and the anticipated performancerequirementsofMAP-21,willassuretimelyattentiontopreservation that will help control futurecosts,especiallyasnewin-ventory comes on line .
MaintenanceProper maintenance of bridge inven-toryincludesongoingtaskssuchasoverlayingbridgedecks,resto-ration of guardrails on the bridge approaches,sweeping,paintstrip-ing,patching,orrepairingorreplac-ingleakingexpansionjoints.Thedepartment’s bridge crews conduct an annual preventive maintenance program .
RehabilitationThis includes replacement of deteriorated bridge elements caused byrustingorspalling(flakingorcrumbingconcrete),repairofcollisiondamage,painting,replacingdamageddeckingandreplacingorrepairing structural elements .
ReplacementEconomic and lifecycle analysis may indicatethatanexistingbridgehasexceededitseconomiclife,andthatbridge replacement is the most cost-effectivechoice.
ResearchBoththedepartment’sResearch,Development and Technology Trans-fersection,andtheFHWA-spon-soredAlaskaUniversityTransporta-tionCenter(AUTC)undertakebridgeresearch,withanemphasisonstruc-tural capacity and seismic demand and performance . The department’s bridge research generally has focusedontheuniqueearthquakeresponse of bridge structures and substructures embedded in frozen ground,andthebehaviorofbridgesatextremelycoldtemperatures.
Allofthesebridgerelatedprojectswere initiated and supported by the Bridge Section .
Overall,thedepartment’sbridgeresearch is aimed at validating the applicability of national bridge designcriteriaforAlaska’sextremetemperature and seismic conditions . Generally,thesestandardshavebeenfoundtobesufficientlycon-servativeandapplicabletoAlaskaconditions,withsomenecessarymodificationsduetotheuniquelymassiveearthquakesthestatecanexperience.
TheAUTCandthedepartment’sBridgeSection,throughaportfolioof nine seismic-related research projectsundertakenwithadditionalpartners,producedresearchleadingto design recommendations that havebeenadoptedbytheAASHTOSeismic Bridge Design guidelines .3
TheAUTCimplementedaremotesensorontheChulitnaRiverBridge,which allows the department to conduct seismic and structural monitoring without sending crews to the site . The data will help deter-mine the necessity of posting load
Replanking the Moose Creek Bridge.PhotobyMichaelKell,ADOT&PF
3 2011AASHTOGuideSpecificationsforLRFDSeismicBridgeDesign,2nd Edition,Chapters7,8.ResearchpartnersincludedNorthCarolinaStateUniversity,China’sUniversityofScienceandTechnology,OregonStateUniversity,andtheUniversityofAlaskaAnchorage.
14|2013AlaskaBridgeReport
restrictionstothebridge.AUTChasalso developed a multi-project port-folio that addresses the impacts of changinghydrologydynamics,suchasglacialandsnowmelt,precipita-tion,seasonalrunoff,andfloodingevents,onproposedbridgecross-ings,especiallyalongnewtranspor-tation and resource development corridorssuchasAmbler,Umiatandthe West Susitna River Valley .
Bridge Age and Construction MaterialsThe state’s bridge inventory con-tinuestoage.AsofJanuary,2013,at least half of the public bridges in the state are 36 years old or older comparedwith33%twoyearsago.Almost15%are50ormoreyearsold.Inall,aboutone-thirdarepastthe mid-point of their 50 to 75-year designlife.Overtime,additionalbridgesarelikelytoshowsignsofdistress as they deteriorate with age.Thus,itiscriticaltoaddresstheexistinginventoryofstructurallydeficientbridges.
The majority of publicly owned bridgesinAlaskahavebeencon-structedusingsteelgirders,fol-lowed by pre-stressed concrete bridges,thentimberbridges,whichtypically comprise the older and shorter spans . Because of their rela-tively low maintenance requirements andrelativelylowcost,pre-stressedconcrete girders are the preferred choice for new construction .
Age of DOT Bridges
Bridge Construction Material
60-103 Years
6%
Timber
7%
Concrete
3%
21-39 Years
36%0-20 Years
28%
Pre-stressed Concrete
41%
Steel
49%
40-59 Years
30%
Hurricane Canyon Bridge on the Parks Highway.ScottSextonADOT&PF
AlaskaDepartmentofTransportation&PublicFacilities|15
Schedule of ImprovementsAsofMay28,2013,ninety-sixhigh-way bridges in the DOT inventory wereclassifiedasstructurallydefi-cient(SeeAppendixB),notcountingbridges that are currently closed . Seventy-fiveofthesebridgesareownedbyDOT,whiletheremain-ing twenty-one are owned by local governments or other state agen-cies . Thirty-eight of these are on the National Highway system; thirty-nineareoff-systembridges,andanadditional nineteen are on-system bridges that are not on the NHS .
Ofthe96structurallydeficienthigh-waybridgesintheDOT&PFinven-tory,theSTIP,orStatewideTrans-portationImprovementPlan,hasidentifiedthirty-fourforreplacementor rehabilitation between 2012 and 2015(SeeAppendixC):twenty-threeontheNHS;sixoff-systembridges;andfiveonnon-NHSfederalaidroutes .
Historically,bridgerehabilitationand replacement has occurred in connection with highway improve-mentprojects,butrecentnationalattention to bridge conditions has resulted in increased funding for“stand-alone”bridgeprojects.FactorsinfluencingAlaska’sshiftin funding for stand-alone bridge projects include the need to improve the state’s infrastructure to support energyandresourcedevelopment,andarecognitionthatthebacklogofstructurallydeficientbridgescould continue growing unless it is addressed .
Project Programming and Planning
STIP FundingTheSTIPhasidentifiedalittleover$350 million in mostly federal fund-ing between FFY 2013 and 2015 for workonoversixtybridges,includingthe rehabilitation or replacement ofthirty-fourbridgesclassifiedasstructurallydeficient.Theworkincludesboth“stand-alone”bridgeprojects,andbridgeworkundertak-en as part of larger projects typically involving highway improvements . In addition to bridge-related project funds,theSTIPalsoidentifiesfund-ing for bridge and tunnel inspec-tions($40.8M2013-2015),seismicretrofit($6.0M2013-2015)andscourmonitoring ($2 .85M 2013-2015) .
Most bridge rehabilitation and re-placement funding comes from the FHWAviaMAP-21,butothersourcesinclude state general fund appro-priations (such as state matching funds for federal funds) and state
generalobligationbonds.Additionalsourcesoffundsincludeapproxi-mately$12millionin“one-time”funds from previously obligated Highway Bridge Program funds un-derSAFETEA-LU,theformersurfacetransportation authorization bill .
Funding for bridges on the NHS shouldbesufficientunderMAP-21,with its emphasis on preservation of NHS assets . More problematic isfundingforoff-systembridgesand for bridges eligible for federal aidbutnotontheNHS.OffSystembridges receive dedicated funding in the Surface Transportation Program category,butataminimumlevelbe-low 2006-2011 averages and insuf-ficienttoaddressoff-systembridgeneeds . Bridges eligible for federal aid but not on the National highway System must compete against all other STP projects in a ‘zero sum’ effort,wherefocusingfundingonbridgeworkmeansunder-investing
New Gakona River Bridge. PhotobyJeffOttesen,ADOT&PF.
16|2013AlaskaBridgeReport
in other elements of the transporta-tion system . Of the 96 structurally deficientbridgesidentifiedinthe2012inspections,39.6%areontheNHS,40.6%areoff-systembridges,and19.8%areeligibleforfederalaid but do not receive NHPP fund-inganddonothavededicated,orset-aside funding through other categories .
The funding level for bridges estab-lished in the Statewide Long-Range TransportationPolicyPlan,based
ondataupdatedin2010,showstheneed for an annual investment of $58millionperyearoverthenexttwenty years to achieve the lifecycle management goals of the plan . This figureisgreaterthanthe$45millioninannualexpendituresidentifiedinthePlanin2006ascorrected,andsignificantlygreaterthanthe$28millionoriginallyforecast.ArevisedlongrangeplandueinAugustof2014willlikelymodifythisnumberfurther .
The department has few options for meeting bridge preservation and replacement needs . The department can hope that additional program-matic funding for bridges above current levels will be available at thefederallevel,butthatappearsunlikely.ItcanrequestadditionalstateGeneralFundsonasustainedbasis,orseekGeneralObligationbonds,sufficienttobringthebridgeinventory into good condition . With-outadditionalfunds,increasingthecommitmenttobridgeworkintheStatewide Transportation Improve-mentPlanwilloccurattheexpenseof other federally funded projects .
WithCongressandtheFHWApressing for a more rigorous asset management approach from each state,itislikelythatasustainedand higher level of funding must be found to ensure that the bridge inventorycanbebroughtto,andmaintained in good condition .
John Orbistondo inspect-ing the Yuikon River Bridge piers. PhotobyLarryDurfee,ADOT&PF.
Shaw Creek Bridge. PhotobySteveRzepka,ADOT&PF.
AlaskaDepartmentofTransportation&PublicFacilities|17
Natural Resource DevelopmentIncreases in energy and metal prices have stimulated a renewed focus on theabilityofexistingbridgestohan-dle large module and construction loads for the energy and resource development industries . Bridges on major NHS routes that provide the corridors to these developments cannot be the limiting factors within the highway infrastructure . Many of these bridges were constructed in the 1940s and 1950s and are reach-ing the end of their design life . They areeitherstructurallydeficientorfunctionally obsolete and need to be replaced to meet the demands of currentuse.(SeeAppendixDforalist of bridges on National Highway Systemroutesscheduledforwork.)
The Alaska Factors
Environmental FactorsAlaska’senvironmentpresentsunique conditions . Freeze/thaw cycles,coastalstorms,meltingper-mafrost,harshwinterconditions,thehighpotentialforearthquakes,allpose challenges to bridge design-ers,totheengineerschargedwithbridgeinspectionandpreservation,andtothemaintenancecrews.Also,due to widespread steep terrain along many high-velocity rivers and streams,scourofbridgefounda-tionsismoreprevalentinAlaskathan in many other states .
Lack of Redundancy in the Highway SystemIt is vital to maintain the bridges that linkAlaska’ssurfacetransportationroutes.Unlikeotherstates,Alaska’shighway system does not have a high degree of redundancy or alter-nate routing . Critical bridges that are out of service can severely constrain the movement of goods and people . This heightens the importance of bridge inspections and the related investments that help maintain a highly functioning surface transpor-tation system .
Repairing pier nosing on the South Fork Koyukuk River Bridge. Photo by EarlRatliff,ADOT&PF.
18|2013AlaskaBridgeReport
Specialized StructuresSignificanttraveloccursinthestate via the state ferry system andbyseaplane.Ramps,classifiedas bridges by the National Bridge InventorySystem(NBIS),linkferryvessels to the uplands at state ferryterminals.TheFHWAclassi-fiesthesespecializedstructuresas functionally obsolete because theyhandleonlyone-waytrafficatlowspeeds;however,theyarewellsuited to their intended purpose and are safe to use .
Likewise,manyofAlaska’ssea-planefloatshavedrive-downrampsfordeliveringfreight,passengers,and luggage directly to the aircraft . Theseramps,alsointheNBIS,arenotdesignedtoFHWAbridgestan-dards as they are usually one-lane wide,handlelowvolumesoftrafficand only accommodate light-duty vehiclessuchasfour-wheelers,vans,andpick-uptrucks.Discus-sionswiththeFHWAmayleadtode-listingseaplanefloatrampsfromtheNBIS.However,de-listingwouldmean that another funding source willbeneededtokeepupwith
inspections and rehabilitation or replacement needs .
TheNBISclassifiestheserampsasfunctionallyobsolete,despitethe high suitability of such special-ized structures for their intended purpose,demonstratingthatbroadnational indicators of infrastructure condition,suchastheNBISratingsystem,canmisstateactualcondi-tions .
Short Inspection SeasonThe department conducts bridge inspections seasonally between AprilandSeptember.Theshortinspectionseason,alongwithavastgeographic area and many bridges locatedinruralandremoteareas,places unique demands on the program .
Snowy Ferry Terminal Ramp.NicAdamsonADOT&PF
Hoonah Floatplane Ramp, Vern Skagerberg, ADOT&PF
AlaskaDepartmentofTransportation&PublicFacilities|19
Thedepartmentstrivestoimplementaneffectivebridgedesign,inspection,andpreservationpro-
gramforAlaskabridges.Withfewerfederaldollarstocovergrowinginfrastructureneeds,partnershipswill become increasingly important to advance Alaska’shighwayprogram,includingrehabilitation,replacement,andconstructionofthestate’sbridg-es.Industry,governmentatthefederal,state,andlocallevels,DOTleadershiptogetherwithstaffonthe“frontlines,”andtheAlaskaLegislature,mustbuild relationships that foster success and the wise andefficientuseofavailablefunds.
To ensure the long-term reliability of the highway system overall,adequatefundingforbridgerelatedworkisvital.Thestatemustcontinuetopreserveexistinginventory,andreplaceaginginventory,particularlyonhigh-volumeroutes and those vital to state commerce where alterna-tiveroutingisdifficultorimpossible.
Closing
M/V Tustumena passengers disembarking at Cold Bay. Photo by Peter Metcalfe .
20|2013AlaskaBridgeReport
Appendices
Nenana River Bridge on the Parks Highway. JoannaReedADOT&PF
AlaskaDepartmentofTransportation&PublicFacilities|21
Asset Management:Abusinessmodelbasedonmaxi-mizingsystemperformance,minimizinglifecyclecosts,improving customer satisfaction, and assuring mea-surable performance standards . State Departments of Transportation recognize Transportation Asset Man-agement as a valuable approach to preserving assets atatimeofgrowingdemandandshrinkingresources.
Bridge: Structures carrying highway traffic which are20 feet or longer . This may include multiple pipe cul-verts where the soil separating adjacent culverts is less than half the adjacent pipe diameter .
Fracture Critical: A fracture critical bridge is definedbytheFHWAasasteelmemberintension,orwithatensionelement,whosefailurewouldprobablycausea portion of or the entire bridge to collapse . Fracture criticalbridgeslackredundancy,whichmeansthat inthe event of a steel member’s failure there is no path for the transfer of the weight being supported by that membertoholdupthebridge.Therefore, failuretypi-callyoccursquickly.
Functionally Obsolete: A bridge that does not meetthe current design standards for lane width, numberof lanes, shoulderwidths, vertical clearances or loadcapacity,presenceofguardrailsontheapproaches,orforsomeotherfeature, isconsideredfunctionallyob-solete.Afunctionallyobsoletebridgemaybeperfectlysafetouse,justnotinconformitywithcurrentdesignstandards .
Maintenance:Ongoing,routinetaskssuchasrestora-tionofguardrailsonthebridgeapproaches,sweeping,paintstriping,patching,orrepairingorreplacingfaultyexpansion joint seals, typically performed by depart-ment maintenance crews .
National Bridge Inspection Standards (NBIS): Federal requirements for inspectionprocedures, frequencyofinspections,qualificationsofinspectors,inspectionre-ports,andloadrating.TheNBISappliestoallbridgestwenty feet or more in length that are located on public roads .
National Bridge Inventory: Structural and rating infor-mation collected by the states and submitted to the Federal HighwayAdministration to fulfill the federalNBIS requirement .
National Highway System: Those elements of the nation’s (and the state’s) surface transportation net-workthataredesignatedbyCongress.TheseincludetheDalton,Parks,Glenn,Seward,Richardson,Alaska,Glacier,Klondike,Haines,SteeseandTokCutoffHigh-waysandadozen ferry terminals,andmajor rail,air,and marine port facilities linked to these highwaysand terminals .
Off-System Bridge:Abridge that isnotapartof thefederal-aid highway system but receives funding through a set-aside in the Surface Transportation Pro-gram.Theseareoftencity,boroughortribally-ownedbridges .
On-System Bridge: Abridgethatisonthefederal-aidsystem. Typically, but not always, these bridges arestate-owned .
PONTIS:Abridgemanagementsystem,PONTIS(notanacronymbut ratheraLatinwordfor“bridge”) isamanagement system software program that stores complete bridge inventory and inspection data, in-cluding detailed conditions of bridge elements . It can calculate system-wide preservation and improvement strategies for use in evaluating the needs of each bridge in the system . It has the capability to generate recommendationsthatderivemaximumbenefitfromavailable funds, report on system-wide and project-levelresults,andforecastlife-cyclecosts.
Preservation: Improvements that extend bridge ser-vicelifeandforestalltheneedformoreexpensivere-pair or rehabilitation .
Rehabilitation: Improvements that exceed bridgepreservationand regularmaintenanceactivities, andwhichincluderetrofittingorreplacingdeckingand/orstructural elements .
Appendix A
Glossary of Terms
22|2013AlaskaBridgeReport
Scour: Erosioncausedwhenfloodwatersorswiftlyflow-ingwaterswashsand,graveland/or rocksaway frombridge foundations . It is one of the three main causes ofbridgefailureinthecountryandasignificantmainte-nanceconcern inAlaska,wherefloodwaterscanposesignificantrisks.
Seismic Retrofit: The improvements made to existingbridges by which they are more resistant to damage or collapseresultingfromearthquakes.
Spalling: Concrete that breaks up, flakes or becomespitted . This is often the result of environmental factors such as freezing and thawing that stress and damage the concrete.Ona low level, concrete spalling canbepurelycosmeticinnature.However,itcanalsoresultinstructural damage when the reinforcing steel (rebar) in-sidetheconcretebecomesexposed.
STIP (Statewide Transportation Improvement Program): Afederallymandatedstateplanforinitiatingfederalaidhighway projects . Projects must be included in the STIP andapprovedby theFHWAbefore fundingauthoriza-tion isgranted.TheSTIP isadynamicdocument,withregular revisions .
Strategic Highway Network (STRAHNET): The total minimum public highway network necessary to sup-port Department of Defense deployment needs . Na-tionwide,ittotalsabout61,000milesofroadincludingthe interstate system and highways that connect to ports and military installations .
Structurally Deficient: Abridgeisconsideredstructur-ally deficient if ratings for the deck (driving surface),superstructure,orsubstructurearepoor.Examplesofpoor condition include corrosion that has caused sig-nificantsectionlossofsteelsupportmembers,move-mentofsubstructures,oradvancedcrackinganddete-rioration of concrete elements .
Tunnel: TheAASHTOT-20 Technical Committee de-fines tunnelsas “enclosed roadwayswithvehicleac-cess that is restricted to portals regardless of type of structure or method of construction . Tunnels do not in-cludehighwaybridges,railroadbridgesorotherbridgesoveraroadway.”Thedefinitionaddsthat“Tunnelsarestructures that require special design considerations that may include lighting, ventilation, fire protectionsystems,andemergencyegresscapacitybasedonthe
AlaskaDepartmentofTransportation&PublicFacilities|23
NHS Bridges (bridges on the National Highway System)
Bridge Name/Number Route Deck Area SF Year Built Status
TrailRiver-610* SewardHighway 9,355 1951 Completed
NoNameCreek-327* HalibutPointRoad 2,415 1959 Construction
BannerCreek-526* RichardsonHighway 1,371 1975 Design
TokRiver-663* TokCutoffHighway 8,228 1963 Design
TulsonaCreek-1250* TokCutoffHighway 3,150 1975 Design
SlanaRiver-654* TokCutoffHighway 6,370 1951 Design
GraniteCreek-328* HalibutPointRoad 3,159 1959 Construction
S.ForkAnchorRiver-666* Sterlinghighway 2,626 1959 Design
RileyCreek-695* ParksHighway 7,713 1969 Design
MuldoonOvercrossing-1322* MuldoonRd.@Glenn 21,313 1976 Design
CampbellCreek/LakeOtis-969 LakeOtisRoad 5,043 1966 Planning
WaterStreetViaduct-797* S.TongassHighway 86,317 1955 Planning
HoadleyCreek-725* S.TongassHighway 2,728 1957 Planning
TolsonaCreek-552* GlennHighway 3,740 1950 Construction
MendenhallRiver-737* GlacierHighway 13,921 1965 Construction
GerstleRiver-520* AlaskaHighway 50,752 1944 Planning
PortageCreekNo.2-631* SewardHighway 8,295 1967 Design
PortageCreekNo.1-630* SewardHighway 6,863 1966 Design
GlacierCreek-639* SewardHighway 5,510 1966 Design
VirginCreek-638* SewardHighway 4,158 1966 Design
PetersonCreek-636* SewardHighway 4,158 1967 Design
TwentyMileRiver-634* SewardHighway 19,191 1967 Design
PhelanCreek-579* RichardsonHighway 2,126 1958 Construction
PlacerRiverMainCross-629* SewardHighway 16,453 1966 Design
PlacerRiverOverflow-627* Sewardhighway 11,094 1967 Design
SnowRiverCntrChannel-605* SewardHighway 22,143 1965 Design
SnowRiverWestChannel-603* SewardHighway 6,414 1965 Design
LittleGoldstreamCreek-678* ParksHighway 2,196 1958 Design
HoldenCreek-1520* DaltonHighway 1,184 1982 Construction
Appendix B
Structurally Deficient DOT & Other Public Bridges
Bridges in each category are listed in priority order from most to least structurally deficient based on structural condi-tion, traffic load and detour length. DOT bridges are indicated by the star (*) symbol. Remaining bridges are owned by other state agencies or local governments. Load-posted bridges are indicated in italics. Lists are based on 2012 inspections and are ‘in-house’ and not FWHA-approved.
24|2013AlaskaBridgeReport
RocheMountoneeCreek-1519* DaltonHighway 1,184 1982 Design
ChickaloonRiver-545* GlennHighway 6,582 1956 Design
ChenaRiver-263* UniversityAvenue 15,509 1963 Design
GulkanaRiver-574* RichardsonHighway 14,213 1974 Planning
ChatanikaRiver-836* ElliottHighway 8,742 1971 Design
RubyCreek-594* RichardsonHighway 799 1952 Design
BearCreek-593* RichardsonHighway 1,318 1952 Planning
CastnerCreek-583* RichardsonHighway 3,963 1958 Planning
UpperMillerCreek-581* RichardsonHighway 4,745 1958 Planning
Non-NHS Bridges (Bridges on Major Collectors and Minor Arterials)KlehiniRiver-1216* PorcupineCrossing 4,521 1969 Design
SnakeRiver-881* NomePortRoad 3,448 1979 Construction
O’ConnorCreek-303* GoldstreamRoad 1,684 1967 Construction
JennyM.Creek-312* ChenaHotSpringsRd. 2,108 1965 NoProject
CrookedCreek-431* SteeseHighway 1,303 1957 Planning
Trollers Creek-864* Knudson Cove Road 2,536 1938 Design
SalmonRiver-444* GustavusAirportRoad 4,047 1976 Planning
S.Fork40MileRiver-839* TaylorHighway 8,658 1977 Design
FishCampCreek-940* NorthwayRoad 1,267 1987 Planning
Seattle Creek-690* Denali Highway 519 1954 Design
Chokosna River-1193* Edgerton Highway 2,062 1973 Planning
KodiakHarborChannel-1189* NearIslandRoad 50,191 1986 Planning
Rock Creek-684* Denali Highway 1,321 1955 No Project
KingSalmonCreek-399* Naknek-KingSalmon 4,110 1960 Design
HerringCove-253* S.TongassHighway 3,468 1952 NoProject
AmericanCreekNo.1-841* TaylorHighway 3,317 1988 Planning
PaulsCreek-402 *Naknek-KingSalmon 3,911 1960 Design
ChenaRiver-532* WendellStreet 17,580 1953 Design
NoyesSlough-209* AuroraDrive 3,818 1960 Planning
Off-System Bridges (Bridges on Local Roads and Minor Collectors)PetersonCreek-383* DotsonLandingRoad 2,553 1940 Design
LivengoodCreek-229* OldElliotthighway 505 1959 Construction
Bauer-Hopkins Trestle-1472 Hopkins Alley 7,644 1950 No Project
Hyder Dock Trestle-1238* Salmon River Road 15,222 1923 Construction
Little Chena River-2057 Section Line Road 1,427 1980 No Project
MooseCreek-401* PetersvilleRoad 2,184 1974 Design
Takotna River-463* Sterling Landing/Ophir 3,596 1941 Design
Little Goldstream Creek-2080 Little Goldstream Road 946 `1984 Design
BlowbackCreek-1541* ToftyRoad 559 1981 Design
AnchorRiver-910* OldSterlingHighway 3,744 1949 Planning
Peterson Street-2263 Peterson Street 919 1955 No Project
NHS Bridges continued
Bridge Name/Number Route Deck Area SF Year Built Status
AlaskaDepartmentofTransportation&PublicFacilities|25
Gate Creek-1185 Subdivision Road 431 1990 Design
Trail Creek-660* Old Tok Highway 697 1951 Planning
NinilchikRiver-427* NinilchikRoad 1,290 1972 Design
Water St. Trestle No. 2-446 Water Street 25,489 1979 Design
Jack Creek-861* Nabesna Road 2,443 1969 No Project
FishCreek-1217* SalmonRiverRoad 1,090 1965 Complete
PorcupineCreek-1635 LoggingRoad 920 1981 NoProject
Archangel Creek-915* Fern Mine Road 350 1995 Planning
Cottonwood Creek-1712 Earl Drive 794 1974 No Project
Unnamed Creek-1835 Koliganek Dump Road 619 1980 No Project
Main Street Pelican-1268 Pelican 34,355 1939 No Project
Sing Lee Alley-1159 Sing Lee Alley 7,640 1945 No Project
SawmillCreek-432* SawmillCreekRoad 5,306 1962 Construction
BarbaraCreek-433* JakolofBayRoad 1,744 1968 Planning
Mineral Creek-944* Mineral Creek Road 1,277 1970 No Project
Water St. Trestle No. 1-389 Water Street 2,959 1920 No Project
BuskinRiverNo.7-988* AntonLarsenBay 2,498 1960 Planning
Thomas Trestle-1473 Thomas Street 7,808 1960 No Project
Little Tok Overflow-659* Old Tok Highway 697 1954 Planning
S.ForkAnchorRiver-1199* NorthForkRoad 1,438 1968 Planning
Otter Creek-461* Happy Creek Road 697 1947 Planning
Unnamed Creek-1556 Koliganek Airport Road 619 1980 No Project
SummerCreek-1686 SummerBayRoad 1,022 1981 Planning
MooseCreek-1985 OilWellRoad 2,149 1998 NoProject
Sayles/Gorge Viaduct-1841 Sayles/Gorge Street 2,416 1960 No Project
Fortune Creek-1958 Cache Creek Road 565 1991 No Project
N. Fork Anchor River-979 Chakok Road 1,484 1987 No Project
IndianCreek-1764 AndersonRoad 1,627 1985 NoProject
Off-System Bridges continued
Bridge Name/Number Route Deck Area SF Year Built Status
26|2013AlaskaBridgeReport
Bridges on the National Highway System
Bridge/Number Route Year Built Year/Action
ChenaRiver-263 UniversityAvenue 1963 >2015Rehab/Replace
GraniteCreek-328 HalibutPointRoad 1959 2013Replace
NoNameCreek HalibutPointRoad` 1959 2013Replace
Snow River-603 Seward Highway 1965 2012 Rehabilitate
Snow River-605 Seward Highway 1965 2012 Rehabilitate
Trail River-610 Seward Highway 1951 2012 Completed
SlanaRiver-654 TokCutoffHighway 1951 2014Replace
TulsonaCreek-1250 TokCutoffHighway 1975 2012/15Replace
TokRiver-663 TokCutoffHighway 1963 2014Replace
Twenty Mile River-634 Seward Highway 1967 2013/14 Replace
RileyCreek-695 ParksHighway 1969 2013Replace
MendenhallRiver-737 GlacierHighway 1965 2014Replace
PhelanCreek-579 RichardsonHighway 1958 2012Replace
PortageCreek#1-630 SewardHighway 1966 2013/14Replace
PortageCreek#2-631 SewardHighway 1967 2013/14Replace
PetersonCreek-636 SewardHighway 1966 2013/14Replace
VirginCreek-638 SewardHighway 1966 2013/14Replace
PlacerRiverOverflow-627 SewardHighway 1967 2013/14Replace
Placer River Main Cross-629 Seward Highway 1966 2013/14 Replace
RubyCreek-594 RichardsonHighway 1952 2015Replace
BannerCreek-526 RichardsonHighway 1975 2015Replace
GlacierCreek-639 SewardHighway 1966 2013Replace
RocheMountoneeCr. DaltonHighway 1982 >2015Replace
Appendix C
Structurally Deficient Bridges Identified for Replacement or Rehabilitation in the 2012-2015 Statewide Transportation Improvement Plan
AlaskaDepartmentofTransportation&PublicFacilities|27
Bridges on the Alaska Highway System/Non-NHS Bridges Bridge/Number Route Year Built Fiscal Year/Action
KingSalmonCreek-399 AlaskaPeninsulaHighway 1960 >2015Rehab/Replace
PaulsCreek-402 AlaskaPeninsulaHighway 1960 >2015Rehab/Replace
S.Fork40MileRiver-839 TaylorHighway 1977 2015Replace
Copper River-339 Copper River Hwy 1977 2015 Replace
Klehini River-1216 Porcupine Crossing 1969 2014 Replace
Local Bridges/Bridges on Low-Volume Routes (Off-System Bridges)
Bridge/Number Route Year Built Fiscal Year/Action
Tatalina River-462 Sterling Loop 1947 2015 Replace
WaterStreetTrestle#2-446 WaterStreet 1979 2014Replace
NinilchikRiver-427 MissionAvenue 1972 2014Replace
LittleGoldstreamCreek-2080 LittleGoldstreamRoad 1984 2015Replace
LivengoodCreek-229 OldElliottHighway 1959 2013Replace
PetersonCreek-383 AmalgaHarborRoad 1940 2013Replace
28|2013AlaskaBridgeReport
Appendix D
Location of Bridges Seismically Retrofitted 1996-2009
AlaskaDepartmentofTransportation&PublicFacilities|29
Appendix E
National Highway System Routes in Alaska
ISLA
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01
A L
E U
T I
A N
I S L
A N
D S
30|2013AlaskaBridgeReport
The Basin Road trestle, rebuilt and reinforced in 2012-2013, is a good example of a functionally obsolete bridge. It is completely safe to use, but with its narrow width, lack of shoulders, and limited load capacity, it is inconsistent with current design standards. Photo by Peter Metcalfe
AlaskaDepartmentofTransportation&PublicFacilities|31
Welding Shear Connectors on the Sam Schuyler Memorial Bridge ShaneGibson,ADOT&PF
32|2013AlaskaBridgeReport
Bridge Inspectors on the Hurricane Gulch Bridge, Parks Highway. PhotobyJohnP.Orbistondo,ADOT&PF
Alaska Bridge Report
Alaska Department of Transportation and Public Facilities
November 2013
Alaska Department of Transportation and Public Facilities
2013