2.36 Bridge Inspections. Introduction. Scope and Objective. Conclusions

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1 Introduction Te Department of Works, Services and Transportation is responsible for construction, inspection and maintenance of bridges in te provincial road system. Te Transportation Services Division as responsibility for roads and bridges. Witin te Division, te Bridge Office is responsible for bridges wereas te Roads Section is responsible for culverts. Te Department s Bridge Inspection Database sows tere are 910 structures wit inspection records, 823 identified as bridges and 87 identified as culverts. Tese culverts include corrugated steel structures referred to as multiplates and various size pipes and configurations but would not include wat is commonly known as ditc culverts. Of te 823 bridges, 715 are six metres or longer and are subject to inspection by a Departmental engineer, 54 bridges are less tan six metres and subject to inspection by igways maintenance staff and te remaining 54 do not ave any lengt indicated in te database. Information on te locations of bridges is maintained in binders of topograpic maps. Te Department s activities relating to bridge inspections include te completion of a bridge inspection report by igway maintenance personnel, regional engineers, and bridge engineers located at ead office. Te Department s policy is to maintain individual files for eac of te 823 bridges. Furtermore, bridge inspection information is entered from te bridge inspection reports to a computerized information system at te Department. In 1996 te Office of te Auditor General identified a number of issues wit te bridge inspection program and recommended te Department establis a bridge inspection program tat included objective standards for assessing bridge conditions and ensuring data in te bridge information system was current and accurate. Scope and Objective We completed our review in December Te objective of our review was to assess weter te Department as: a bridge inspection program wit objective standards for assessing bridge conditions, a bridge information system tat is current and accurate and a reabilitation and replacement plan based on information gatered from bridge inspections. Conclusions Te Department as a bridge inspection policy; owever, it is not documented and tere is no documented approval of te policy. Te bridge inspection policy is not risk based; instead, te policy is to inspect bridges six metres or longer every two years. A bridge may be inspected more frequently if te Bridge Office is made aware of safety issues; owever, tis is a reactive inspection and not proactive based on bridges wit te igest degree of risk for safety. Contrary to te Department s policy to inspect bridges six metres or longer every two years, 379 of te Auditor General of Newfoundland and Labrador 543

2 715 bridges requiring suc inspection ave not been inspected witin te past two years. Furtermore, 47 of tese 379 bridges ad an overall rating sowing tat tey were in a poor or unsafe condition and 39 of te 379 bridges did not ave an overall rating. Te Department does not ave documented guidelines to assist te five regional engineers and six bridge engineers wen completing bridge inspections to ensure tat inspections are consistent among staff and across regions. Our review indicated tere were inconsistencies in bridge condition ratings resulting from completed inspections. Te bridge inspection database maintained by te Department containing information input from te bridge inspection reports is incomplete and inaccurate. For example: At te time of our review in December 2002, te bridge inspection database did not include information on inspections performed after Fourteen bridges were not in te database and twelve bridges included sould ave been removed. Information on te lengt of 54 bridges is not included in te database. As a result, it is not possible, from our review of te database, to determine weter tese bridges were six metres or longer and weter tey sould be inspected by engineers witin te two year inspection requirement. 54 bridges in te database did not ave an overall rating. Not all information relating to te condition of te bridges is entered into te database. For example, te results of load tests to determine te safety of a bridge is not entered. Te Department s process relating to bridge reabilitation and replacement requires improvement. For example: Te Department does not ave a long-term plan to enable Government to consider future funding requirements in an orderly manner and to estimate ow muc funding will be required or wen te funding would be required to reabilitate or replace ageing bridges so tat all bridges are brougt up to a fair or good condition. Tis may also elp avoid a significant fiscal burden of reabilitating or replacing a large number of bridges in a sort time-frame. Altoug te Department s database does provide for 544 Auditor General of Newfoundland and Labrador

3 input of information regarding suggested reabilitation and replacement cost and date, we found tat 202 of te 360 bridges indicated as being 30 years of age or older did not ave any estimates for future reabilitation or replacement costs or te dates tat te work sould be completed. Te Department does not use a risk based model to identify bridges for reabilitation or replacement. Instead, on an annual basis te Bridge Office uses listings prepared by te five regions along wit teir own knowledge of bridge conditions and opinions wit regard to safety and economics to set its annual work priorities. Officials at te Department ave indicated tat te funding for te bridge maintenance program is not sufficient. If te required maintenance is not performed on bridges, tere will be extra costs for reabilitation work and te work will be required sooner. Findings and Recommendations Bridge inspection is necessary to determine te safety of bridges on our igways and to determine required maintenance, reabilitation and replacement. In order for te Department to apply a risk model to determine te priority and frequency of bridge inspections and to determine te priority for maintenance, reabilitation and replacement, it requires detailed information about eac of its 715 bridges. A complete and accurate bridge information database would be a useful tool to identify tis information. Our review of te Department s bridge inspection program indicated te following: Bridge Inspection Policy Te Department s bridge inspection policy is not risk based; instead, te policy is to inspect bridges at least every two years. A bridge may be inspected more frequently if te Bridge Office is made aware of safety issues; owever, tis is a reactive inspection and not proactive based on bridges wit te igest degree of risk for safety. Bridge inspections are not always being performed in accordance wit Departmental policy wic requires tat bridges six metres or longer be inspected at least every two years. Figure 1 sows tat 379 ( ) of te 715 bridges ave not been inspected in te last two years and tat 47 of tese 379 bridges ad an overall rating sowing tat tey were in a poor or unsafe condition. A furter 39 of te 379 bridges did not ave an overall rating. Auditor General of Newfoundland and Labrador 545

4 Figure 1 Bridge Inspection Bridges six metres or longer Last Inspection Good Fair Overall Rating Poor Unsafe Not Rated Totals < 2 years > 2years <5 years > 5 years < 10 years > 10 years Totals Source: Department s Bridge Inspection Database Bridge inspection reports are not required to be completed for bridges under six metres. In 1997 te Bridge Office decided not to require regional office engineers to inspect bridges less tan six metres in lengt and opted to ave igway maintenance staff perform inspections of tose structures. Inspections of bridges six metres and over are documented by an inspection report and entered into te Department s database wereas any inspection reports prepared by maintenance staff are not required to be entered into te database. If tere is any question of bridge safety by igway maintenance staff tey are required to request inspection of te structure by engineers in eiter te regional office or te Bridge Office. Te Department s bridge inspection policy is not documented and tere is no evidence te policy is approved. Two of te six bridges identified in te database as being unsafe were indicated in te database as requiring furter inspection by te Bridge Office; owever, tere was no documentation in te bridge files to substantiate tat furter inspections were carried out. We were unable to determine weter te appropriately qualified personnel completed inspections of 289 of te 715 bridges because te database did not indicate wo performed te inspection. A furter review of te 289 records sowed 70 were eiter not rated or rated poor to unsafe and 66 of te 70 were inspected more tan 2 years ago. 546 Auditor General of Newfoundland and Labrador

5 Bridge Inspection Guidelines Te Department does not ave documented guidelines to assist te five regional engineers and six bridge engineers wen completing bridge inspections. Guidelines are necessary to increase te objectivity of te ratings, to ensure consistency in rating te condition of bridge components by engineers in eiter te Regional Offices or te Bridge Office, and to ensure tat bridge inspection forms are properly completed. Guidelines are also necessary so igway maintenance staff or regional office staff are aware of wic specific bridge deficiencies are to be referred to te Bridge Office for furter inspection. For 98 of te 715 records included in te database we found tat te general overall condition was eiter not rated or was rated better tan te condition of te substructure and/or te superstructure. Discussions wit staff at te Department confirmed tat te overall bridge rating sould be no iger tan te lowest rating for te substructure and/or te superstructure. Tis indicates tat, as a result of not aving inspection guidelines, tere are inconsistencies in te bridge condition ratings. As an a example, te Winterouse Brook Bridge was rated overall as good wile te superstructure was rated as poor. Winterouse Brook Bridge Auditor General of Newfoundland and Labrador 547

6 Te bridge inspection forms were not always fully completed. For example: 35 structures were indicated as being over navigable or nonnavigable water; owever, tey were not rated for adequacy of waterway. 297 structures did not ave ratings for bearings yet 220 of te 297 were rated for bearing seats. Tere may be exceptions but tis is generally inconsistent because a structure wit a bearing seat would normally be expected to ave a bearing tat sould be rated. Bridge Information Information at te Department sows tere are 910 structures wit inspection records, 823 identified as bridges and 87 identified as culverts. Te Department maintains information on tese structures in tree forms - a Bridge Inspection Database, a ard-copy file, and a series of topograpic maps wic indicate te location of various structures. Given te number of bridges in te Province, it is important tat te Department as a means to keep accurate information on teir condition. Our review indicated te following: Te Bridge Inspection Database is intended to capture information on te bridges in te Province and could be used to prioritize and manage inspections as well as maintenance, reabilitation and replacement. Terefore, it is necessary tat te database contain information tat is complete and accurate. We found tat te database was neiter complete nor accurate. For example: At te time of our review in December 2002, te bridge inspection database did not include information on inspections performed after bridges were not in te database: 3 were no longer part of te provincial road system and 11 were existing structures tat were missed. Te tree bridges wic are no longer part of te provincial road system are used for cabin access and, terefore, sould be in te database and inspected. Of te 11 tat were missed, 7 were constructed in bridges were incorrectly included in te database: 6 were duplicates, 5 were not te responsibility of te Department, and 1 was demolised. 548 Auditor General of Newfoundland and Labrador

7 54 bridges in te database did not ave information wit respect to lengt. Terefore, as te database did not indicate weter te bridges were six metres or longer, we were unable to determine, from our review of te database, weter tese bridges sould be inspected by engineers in eiter te regional offices or te Bridge Office every two years. Twenty nine of tese 54 bridges ave not been inspected since 1997 or earlier. 54 bridges in te database did not ave an overall rating. Not all information relating to te condition of te bridges is entered into te database. For example, te results of load tests to determine te safety of a bridge is not entered. Altoug te Department maintains a ard-copy file for te bridges, not all information is included. For example, inspection reports, load test results, and non-routine Bridge Office inspection results are not always put in te file. Bridge Reabilitation and Replacement Te Canadian Higway Bridge Design code, te standard for bridge construction indicates tat, until recently, a 50-year life was assumed. Te actual life of a bridge can differ from tis assumption depending on many factors suc as te amount and weigt of traffic, and use of road salt on te structure. In addition, te 50-year life estimate is contingent on regular maintenance and reabilitation being undertaken, if not, te expected lifespan would be sorter. Regular maintenance is a yearly activity and would consist of, for example, cleaning out expansion joints, patcing oles in te aspalt and clearing curbs of sand and salt accumulated from winter ice and snow control. Reabilitation is generally completed in te range of 25 years after construction and could involve replacement of girders, deck, andrails or curbs. Suc reabilitation can restore a bridge to near te condition at construction. Only 615 of te 715 bridges in te database as information on te year of construction. Te average age of tese 615 bridges is 29.3 years. Information on te age and condition of te bridges is outlined in Figure 2. Auditor General of Newfoundland and Labrador 549

8 Figure 2 of bridges by age Latest inspections to 31 December 2001 Overall Rating Bridge age Good Fair Poor Unsafe Not Rated Totals Not in database Totals Source: Department s Bridge Inspection Database As Figure 2 sows, after 29 years, tere are proportionately more bridges rated as being in a poor or unsafe condition. Terefore, as te average age of bridges is 29.3, it is likely tat significant funding will be required in te future to maintain te bridges in a good condition. Our review of te Department s maintenance, reabilitation and replacement program for bridges indicated te following: Te Department does not ave a long-term plan to estimate ow muc funding will be required or wen te funding would be required to reabilitate or replace ageing bridges so tat all bridges are brougt up to a fair or good condition. Altoug te database does provide for input of information regarding suggested reabilitation and replacement cost and date, we found tat 202 of te 360 ( ) bridges indicated as being 30 years of age or older did not ave any estimates for future reabilitation or replacement costs or te dates tat te work sould be completed. Te development of long-term plan is necessary to enable Government to consider future funding requirements in an orderly manner and avoid a significant fiscal burden of reabilitating or replacing a large number of bridges in a sort time-frame. 550 Auditor General of Newfoundland and Labrador

9 Te Department does not use a risk based model to identify bridges for reabilitation or replacement. Instead, on an annual basis eac of te five Regions submit a prioritized listing of bridges for reabilitation and replacement based on teir knowledge of te region. Te Bridge Office uses tese listings along wit teir own knowledge of bridge conditions and opinions wit regard to safety and economics to set its annual work priorities. Altoug te Department s database could be used as a source of information to set priorities for bridges relative to all oter bridges in te Province, as a result of te incompleteness and inaccuracies in te database, it is not possible for te Department to use it to request funding for te igest risk bridges in te Province. Officials at te Department ave indicated tat te funding for te bridge maintenance program is not sufficient. If te required maintenance is not performed on bridges, tere will be extra costs for reabilitation work and te work will be required sooner. Recommendations Te Department sould: develop and implement a documented and approved risk based bridge inspection policy; prepare guidelines to ensure tat inspections are consistent among staff and across regions; ensure tat te bridge inspection database is complete and accurate; develop and implement a long-term plan for future funding requirements for te reabilitation and replacement of bridges. Department s Response Te Department is developing a risk-based bridge inspection policy. Tis policy will be furter developed to include guidelines for engineering staff in te application of te policy. As well, a seminar will be eld wit regional staff in May 2004 to review tese guidelines and ensure consistency in bridge inspections. Te Department is committed to improving te bridge inspection process, wic will require increased engineering staff time applied to report generation and data entry. Improvements to te database ave been initiated, wit a focus on data Auditor General of Newfoundland and Labrador 551

10 processing integrity and te reorganization of te forms used for data collection. At present, te Department as four bridges wic are labelled unsafe in te database. Tese ratings were assigned by te person at te regional level wo did te inspections. Follow up inspections were done by a Senior Bridge Engineer or te Cief Bridge Engineer. Tese more detailed inspections indicated no imminent safety concerns and were upgraded from unsafe. It is acknowledged tat te database was not upgraded to reflect tis cange. Had tese inspections indicated oterwise, immediate action would ave been taken. Two of tese bridges are on cabin roads or oter low volume roads, wit very ligt traffic. Te department is still assessing its options wit respect to tese bridges. Te oter two bridges are on department maintained roads and are monitored regularly. Tey ave bot been identified for consideration for reabilitation in te next fiscal year. Wit respect to te funding situation of te bridge program, te Department strives to optimize te funding allocation available for reabilitation and replacement of provincial bridge structures. Te Department will continue to evaluate all structures for load capacity, wit priority given to te routes most affected by eavy loads. Te Department is currently developing an eigt year program to address te issues related to aging bridge infrastructure. 552 Auditor General of Newfoundland and Labrador