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Ms.KristineGiga <br />March2009 <br />24, <br />Pageof3 <br />WeassumethatURSdeterminedtheexistingbridgecansustaintheadditional <br />l'-2"ofdeckwidthforthenewsidewalk,pertheCooperativeAgreement <br />ProgramApplicationdatedOctober11,2006.Priortomovingforwardwiththe <br />wideningproject,wehighlyrecommendtheCitybetterunderstandthecondition <br />oftheexistingbridgebeyondsimplevisualobservations.Thestructureisnearly <br />50yearsoldandiscurrentlyfunctionallyobsolete.Werecommendmorein- <br />depthanalysisofthestructurebeconductedbeforecommittingCityfundstothis <br />structure. <br />WesuggestthatMn/DOT,asthebridgeowner,provideadditionaltestingofthe <br />existingbridgedeck.Thistestingwillbetterdeterminetheconditionofthe <br />existingconcretedeckbelowtheoverlay.Thesetestscanincludebothnon- <br />destructiveanddestructivetesting.Non-destructivetestscanincludeachain- <br />dragoftheexistingdecktodeterminetheextentofdelaminatedconcrete. <br />Destructivetestingcouldincludechloride-iontesting,partialexposureofdeck <br />rebar,andconductivityteststoevaluatethelevelofcorrosiononthenon-epoxy <br />coated(black)reinforcingbars. <br />ThesetestsarerelativelysimpleandwouldsubstantiallyhelpMnlDOTandthe <br />Cityevaluatewhatimprovementsshouldbeconsideredforthisstructure.Alocal <br />independenttestinglaboratorycouldprovidethisinvestigation,likelyunder <br />$4,000.Mn/DOTcouldpotentiallyutilizemaintenancefundsforthistesting. <br />Thisismoneywellspentwhenconsideringaninvestmentofover$350,000. <br />Ifthedeckstructureisfoundtobeingoodcondition,werecommendtheCity <br />collaboratewithMnlDOTtoprovideadeckwideningandbridgemaintenance <br />project.Theexistingstructurewouldneedstructuralanalysisandgeometric <br />standardreview;thisanalysishasbeenincludedinourbridgewideningfee. <br />Assumingthebridgeisviablestructurallyandgeometrically,theCitycoulduse <br />itsfundsforthedeckwidening,whileMn/DOTcouldusemaintenancefundsfor <br />deckrepairsandjointreconstruction.Bothagencieswouldrealizecostsavings <br />byhavingonecontractorprovidetherepairsandwidening. <br />Ifthedeckisfoundtobeinpoorcondition,ornotstructurallysuitablefor <br />widening,werecommendtheCityreconsiderthewideningproject.Mn/DOT <br />shouldthenre-evaluatetheconditioncodingofthebridge.Sincethisstructureis <br />ownedbyMnlDOT,StateTransportationFunds(BridgeBonding)cannotbe <br />usedtoreconstructthebridge. <br />Werecommendwhatevercourseispursued,thattheCityworkstogetherwith <br />Mn/DOTtodeterminethebestcourseofaction. <br />Cc:BethEngum,P.E.-KHA <br />JerryPertzsch,P.E.-KHA <br />MarkPribula,P.E.-Mn/DOT <br />PaulKivisto,P.E.-MnlDOT <br />