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CHAPTER 4. CASE STUDIESINTRODUCTIONThis chapter summarizes three case studies that practitioners recommended as part of the survey.The three case studies are as follows: Table 41. Case Studies. Construction State Project Status Cost Bridge reconstruction and new pedestrian bridge Colorado Completed in November 2017. $150 million construction on State Highway 82 (SH 82) Highway widening project on US 281: Segment 1 was completed in Texas Segment 1 (Loop 1604 to Stone Oak) August 2021. $349 million Segment 2 (Stone Oak to Bexar County Line) Phase 2 is nearing completion. Virginia Hillsboro Improvement Project Completed (May 2021). $15 millionCOLORADOâSH 82 BRIDGE RECONSTRUCTION AND NEW PEDESTRIANBRIDGE CONSTRUCTIONProject OverviewThe Grand Avenue Bridge Replacement project involved replacing and realigning the existingbridge on SH 82 over a railroad track, the Colorado River, and Interstate (I) 70 in GlenwoodSprings (Figure 16). Initial work included construction of platforms (also called causeways) atthe pier locations on the south bank of the Colorado River. Crews then installed a temporarywalkway on the existing SH 82 vehicular bridge, followed by the removal of the pedestrianbridge and replacement with a new one that could carry existing utility facilities. (Note: theutility facilities were attached to the old vehicular bridge.) Work then focused on theconstruction of a new vehicular bridge. Traffic on the existing bridge was maintained until thefall of 2017, after which the bridge was closed, and traffic was rerouted while the new vehicularbridge was under construction.The old Grand Avenue Bridge was built in 1953 as a two-lane bridge with a sidewalk on eachside. The sidewalks were removed in 1969 to make way for two additional travel lanes. Apedestrian bridge was subsequently built. In 2009, the Colorado state legislature passed a bill tofund a program (called the Colorado Bridge Enterprise program) to address the stateâs poorlyrated bridges. The Grand Avenue Bridge was one of approximately 150 bridges on the statesystem that had a poor rating and therefore had priority for the funding. Work on anenvironmental assessment for the project began in summer 2011 after a CDOT study found thebridge to have functional, structural, and safety deficiencies. The final budget for the project was$126 million, which included contributions from the state and contributions from utility ownersand several local governments, including the city of Glenwood Springs, Garfield County, andEagle County. 92
OpenStreetMap© (https://www.openstreetmap.org/copyright) Figure 16. Grand Avenue Bridge Project in Glenwood Springs, Colorado.The existing bridge consisted of nine spans with three steel units of concrete pier foundations. Ithad insufficient vertical and horizontal clearances, as well as narrow 9-ft 4-in lanes with noshoulders. The deck and girders did not meet current design standards. Replacement of thebridge widened the existing lanes and improved the load of the deck and girders. The projectincluded a five-leg roundabout at the 6th Street and Laurel Street intersection to optimize trafficcirculation between I 70, SH 82, 6th Street, and Laurel Street.The existing pedestrian bridge was not included in the original project scope and therefore wasnot included in the environmental review. One of the reasons was that the pedestrian bridge hadbeen renovated recently. Prior to the environmental review, the original project scope included avehicular bridge replacement using the original alignment, with minimum anticipated right-of-way and utility relocation issues. As the preliminary design progressed, it became clear thataddressing current and future pedestrian and bicyclist needs would be critical. It also becameclear that the utility attachments to the existing vehicular bridge would constitute a majorchallenge during the construction phase. A recommended alternative was to use the pedestrianbridge to facilitate the relocation of existing utility facilities that were attached to the vehicularbridge. However, the existing pedestrian bridge did not have the capacity to hold these facilities,which made it necessary to include replacing the pedestrian bridge as one of the design options. 93
CDOT followed a context sensitive solutions approach for the development of the project. Thisapproach involved participation by a wide range of stakeholders to preserve scenic, aesthetic,historic, and environmental resources, while ensuring safety and mobility.CDOT selected a construction manager/general contractor (CM/GC) project delivery method forthe SH 82 project. CDOT had used a CM/GC approach on another bridge project successfullyand decided that using the approach for the SH 82 project would add value to the project. TheCM/GC contractorâs involvement started early during the concept development phase to help thedevelopment team brainstorm ideas on how to minimize construction time and impacts toGlenwood Springs. The CM/GC contractorâs participation was also critical as the projecttransitioned from pre-construction to construction to help keep institutional memory and managerisks.Significant construction milestones included the following: ⢠March 2016: Construction of the south causeway was complete. Temporary pedestrian walkway on vehicular bridge opened. ⢠April 2016: Demolition of the existing pedestrian bridge. ⢠March 2017: New pedestrian bridge opened for public use. ⢠August 2017: Construction of the north causeway along the Colorado River was complete. ⢠August 2017: Traffic bridge detour/closure. ⢠December 2017: New Grand Avenue bridge was completed. Completion of 6th and Laurel roundabout. Completion of River Street. Completion of SH 82 and I 70 exits. ⢠February 2018: Completion of Glenwood Hot Springs lot. ⢠March 2018: Causeway removal complete. ⢠June 2018: Landscaping finalized.Management of UtilitiesAs mentioned, the new pedestrian bridge was designed to carry the existing utility facilities thatwere attached to the old vehicular bridge. The utility relocation design involved converging allexisting lines into a vault, and then elbowing up to the underside of the pedestrian bridge. Fourutility owners agreed to contribute a total of $3 million toward the construction of the newpedestrian bridge, with the relocated utility facilities accommodated on the new bridge viapermit.The SH 82 project was complex from a utility coordination perspective. To reduce the risk ofdelays during construction, it became clear that the existing utility facilities that were attached tothe existing vehicular bridge would need to be relocated during the first phase of the project. Tofacilitate the utility coordination process, CDOT implemented a utility engineering-basedprogram that included early utility investigations during project deliveries, early identificationand resolution of conflicts, and frequent coordination with utility owners. Based on the positiveresults that CDOT experienced with this project, CDOT decided to extend the program to otherparts of the state. Figure 17 shows the current workflow of the CDOT implementation, showingphases during project delivery when utility investigations should be conducted and how theresulting deliverables feed other related activities. 94
Figure 17. Utility Engineering Project Lifecycle (adapted from [106]).Anticipated right-of-way and utility impacts associated with the preferred alternative includedthe following: ⢠Severance of Union Pacific Railroad tracks to construct a local detour for a 95-day bridge closure shutdown period. ⢠Closure of a resort parking lot for 14 months. ⢠Utility relocations.The project had few UR issues during construction. A conflict between a new 24-in stormdrainage reinforced concrete pipe (RCP) and an electrical conduit was resolved easily within aday thanks to the coordination between the contractor, the utility owner, and the hydraulicengineer.The project had a construction management consulting contract, which included utilityinspections. The project included the preparation of utility as-builts.Change OrdersCDOT registered 39 change orders for this project from July 2016 to November 2019. Most ofthe change orders resulted in a change in dollar amount. In total, change orders represented$3 million, with plan or specifications errors being the most common reason, followed by DSCsand changes in materials. Two of the change orders were related to time additions. The first oneadded 30 days in relation to concrete slope paving. The second one added 129 days in connectionwith a Union Pacific Railroad storm drainage. 95
None of the change orders had a utility delay reason code. One change order was classified asdifferent site conditions, but the description field showed âPedestrian Bridge F-07-BA Utilities.âThe change order did not include any additional information. The approved change order amountwas $97,900.TEXASâUS 281 WIDENING TO 6-LANE FREEWAY WITH 2-LANE DIRECTIONALFRONTAGE ROADSProject OverviewThis project involves widening 8 km (5 mi) on US 281 in San Antonio, Texas, from a four-lanemedian-divided cross section to a six-lane freeway with two-lane directional frontage roads. Thisproject is Segment 2 of the US 281 project and extends from Stone Oak Parkway to the BexarCounty line (Figure 18). This project is currently underway, nearing completion. Segment 1,recently completed, went from Loop 1604 to Stone Oak Parkway. This segment is 4.8 km (3 mi)miles long.North San Antonio has undergone aggressive growth for the last few decades. South of Loop1604, the district had already expanded US 281 to a freeway configuration with frontage roads,but north of Loop 1604, US 281 was constrained to a four-lane median-divided cross section. Abottleneck at Loop 1604 effectively caused miles-long congestion, particularly in the northbounddirection during the evening peak hours.The district had explored a range of stopgap measures to mitigate congestion over the years, untilfunding became available to undertake a more comprehensive freeway expansion project. Whenfunding became available, the district went ahead with an accelerated schedule to design andbuild the project. The district completed an environmental impact statement in July 2015. ForSegment 1, the district completed 30 percent plans in February 2016, 60 percent plans in June2016, and 100 percent plans in December 2016. The project went to letting in February 2017.The winning bid for Segment 1 was $192 million. Construction started in August 2017 andended in March 2023. For Segment 2, the district worked on the preliminary design in 2016 andthen completed 30 percent plans in June 2017, 60 percent plans in September 2017, and 100percent plans in March 2018. The project went to letting in July 2018. The winning bid forSegment 2 was $178 million. Construction started in February 2019.Segment 1 was designed in 2D. The bid package included 11Ã17-inch sheets that included planviews, cross sections, and profiles. The district designed Segment 2 in 3D. Most aspects of thedesign were in 3D, but the traffic control plan, phasing, and utility coordination were not. Allutility files were in 2D. The research teamâs understanding is that 3D utility files were eventuallyprepared, but they were not integrated into the projectâs 3D environment. Although the projectwas designed in 3D, the bidding package was prepared using 11Ã17-inch sheets that includedplan views, cross sections, and profiles.Segment 2 had two key UR features. The first feature was that the district included the project inthe pilot UCM implementation that TxDOT rolled out in 2016. This implementation was part ofthe FHWA SHRP2 UCM implementation program. The UCM implementation for Segment 2included the preliminary design and detailed design phases. The second feature was that the CEI 96
contract included utility coordination and utility inspection services. Most utility owners tookcare of their own relocations, whether reimbursable or not. Some utility relocations wereincluded in the highway contract. TxDOT calls these relocations joint-bid relocations.OpenStreetMap© (https://www.openstreetmap.org/copyright) Figure 18. US 281 Highway Widening Project.Management of UtilitiesFor Segment 1, officials who had a working knowledge of what happened during the design orconstruction phases had moved on. For Segment 2, the research team was able to gather moredetailed information about the management of utilities.Preliminary Design and Final DesignFor Segment 2, district utility staff stressed the need for early utility coordination and conductedQLB and QLA utility investigations in preparation for the 30 percent design plans. To identifyand manage utility conflicts, the district used a template in Microsoft® Excel® format. Thedistrict also showed the location of all utility conflicts on working project files along with theircorresponding identifiers, which matched the records in Excel (Figure 19). The districtdocumented and resolved 316 utility conflicts. Most utility conflicts were resolved via relocation.In a few cases, the district found changes to the highway design to avoid existing utility facilities. 97
Courtesy of the TxDOT. Figure 19. Utility Conflict Locations on Working Project Files.The utility conflict list template included two spreadsheets. The first spreadsheet listed all theutility conflicts and the corresponding resolution strategy. The second spreadsheet documentedthe alternatives the district considered to resolve significant utility conflicts. The district foundthe UCM template to be beneficial and subsequently decided to use it in other projects. TxDOThas used an updated version of the utility conflict template (Figure 20, Figure 21) for many otherprojects throughout the state and is recommending UCM as a standard practice at thedepartment.An early focus of the UCM implementation was to find opportunities to avoid unnecessaryrelocations. For example, an overhead electric transmission line crossing the highway was inconflict with an overpass (Figure 22). The overhead clearance was insufficient. The districtconsidered two alternatives: (a) relocate the transmission line and (b) modify the final grade toavoid the transmission line. After considering the advantages and disadvantages of bothalternatives, the district decided to lower the final grade. Part of the tradeoff analysis was tomake sure that lowering the final grade would not affect minimum coverage requirements for anexisting gas line at that location. Avoiding the transmission line resulted in an estimated savingsof $3 million and 24 months of project delivery time. 98
Utility Conflict Management (UCM) - Utility Conflicts Utility Utility Utility Owner Utility Utility Owner UtilityConflict Layout/ Utility Owner Contact Phone and Feature Utility Type Utility Subtype Utility Feature Size Material Utility Conflict Description Contact Name Function ID Sheet No. Email ID Placement Property Parcel Start Start End End From From Height/ Alignment Placement Relative to Parcel U- Station Origin To Latitude To Longitude Relative to Interest Acquisition Station Offset Station Offset Latitude Longitude Depth (ft) Type Existing ROW Number Ground Level Type Status Utility Utility Utility Estimated Test Hole Resolution Strategy Selected Reimbursable High Priority StatusInvestigation Investigation Next Action Conflict Resolution Comment No. (from Resolution Alternatives) (Y/N) (Y/N) Achieved Date Completed Needed Status Date Figure 20. Utility Conflict List Template â Spreadsheet No. 1 (Utility Conflicts). 99
Utility Conflict Management (UCM) - Analysis of Utility Conflict Resolution Alternatives Utility Total Cost Alternative Impact on Project Total Cost Total Cost Feasible SelectedConflict Alternative Description Alternative Advantages Alternative Disadvantages to Utility No. Delivery Time to DOT ($) ($) (Y/N) (Y/N) ID Owner ($)Utility Conflict Management (UCM) - Utility Conflicts Owner/District: Prepared By: Project CSJ: Reviewed By: Project Name: Date: Utility Utility High Utility Estimated Utility Owner and/or Utility Type and Size and/or Start Start End End Util. Inv. Util. Inv. Test Next Action/ResolutionConflict Layout/ Utility Conflict Description Priority Conflict Resolution Contact Name Feature Material Station Offset Station Offset Compl. Needed Hole No. Strategy Selected ID Sheet No. (Y/N) Status Date Figure 21. Utility Conflict List Template â Spreadsheet No. 1 (Utility Conflict Resolution Alternatives). 100
Courtesy of the TxDOT. Figure 22. Overhead Transmission Line in Conflict with Highway Overpass.A 24-inch water main running longitudinally was in conflict because it was too close to thesouthbound frontage road. The district considered two alternatives: (a) relocate the water mainand (b) shift the frontage road alignment approximately 5 feet closer to the main lanes. Afterconsidering the advantages and disadvantages of both alternatives, the district decided toredesign the frontage road closer to the main lanes. Avoiding the water main resulted in anestimated $1.6 million in savings. Project delivery time savings were not significant because therelocation would have been included in the highway contract and the impact on constructionschedule would have been negligible.These two examples, as well as other instances in which the district avoided utility facilities,happened early during the preliminary design phase. As a lesson learned, the district did notdiscuss these resolution strategies with the affected utility owners and simply adopted thosestrategies on its own. Discussing with the utility owners how the district helped them avoidcostly utility relocations would have been beneficial during the construction phase when thedistrict encountered a few situations that required the water utility owner to be cooperative, butthe utility owner was reluctant to participate actively.Overall, the district quantified $4.6 million in economic savings and 24 months in projectdelivery time. The district also reported positive benefits from the implementation of the UCMapproach at other projects. 101
In addition to avoiding existing utility facilities whenever possible, the district tried to completeutility relocations before letting. For Segment 2, the district used a right-of-way clearing contractto accelerate utility relocations prior to letting. This type of contract was relatively new at thedepartment at the time the district used it for Segment 2. Given the positive results, TxDOT hassince expanded it to other districts.Construction PhaseFor utility relocations that could not be completed prior to letting, the district staged therelocations to minimize impacts to the construction schedule. The district did not integrate utilityrelocation schedules into the contract schedule but did prepare an Excel file showing the plannedrelocations for all utility facilities. In addition, the district prepared a document to manage utilityrelocations during construction, called a construction management plan (CMP). CMPs have beenrequired at TxDOT since 2016 in situations where a district estimates that complying withcertifications and permit clearances is likely to extend beyond 3 months after letting (107). ACMP describes the sequence of highway construction that can be completed in conjunction withthe outstanding certification and permit items. CMPs are applicable to any certifications orpermits needing to be cleared after letting that will not be incorporated into the projectconstruction but will be completed by a third party.CMPs can be included in the highway contract at the discretion of the project manager. In thecase of the US 281 project, the CMP was not included in the contract and therefore it was notenforceable. Nevertheless, the district indicated that compliance with the CMP was at 88 percent,meaning that 88 percent of utility relocations that were included in the CMP were completed ontime according to the CMP. District officials indicated that this level of compliance was positiveand encouraging.As mentioned, although the project was designed in 3D, the bidding package contained 11Ã17-inch sheets containing 2D plan views, cross sections, and profiles. It is not clear whether thehighway contractor received a copy of the 3D files. In practice, field personnel only used the11Ã17-inch sheets. Feedback from the construction manager and CEI personnel indicates thathaving 3D files would have been beneficial during the construction phase.For non-joint-bid relocations, the CEI consultant highlighted the need for extra coordination withutility owners because the contractor wanted to work on several fronts simultaneously (asopposed to south-north, as originally envisioned during the design phase). The consultant alsohighlighted the need for utility owners to be flexible during construction. In addition, it wascritical to develop effective working relationships with utility contractors.Some utility pole relocations were problematic. The typical staging process for poles involvesthe following steps: ⢠A utility owner technician prepares drawings depicting the approximate location of the poles. This step involves the use of a GIS-based platform that does not include accurate georeferencing. Although it was not immediately clear, it appears that these drawings are used to prepare and execute utility agreements. 102
⢠A utility owner representative goes to the field with this drawing to stake actual pole locations based on commonly accepted practices. ⢠A surveyor with the CEI consultant surveys the staked locations. ⢠An engineer overlays this information on project files and checks for conflicts with other utility facilities or project features such as culverts.An issue in practice was electric utility contractors placing poles not according to previouslystaked locations (or agreed upon locations), but according to what was convenient to the utilitycontractor (e.g., moving the pole location a few feet so that their truck could access thatlocation). Another issue was utility poles that were relocated prior to letting but were not shownon the plans the contractor received from TxDOT.Poles near retaining walls required special attention. Although TxDOT staked the locationswhere poles were supposed to be installed, in a few cases the utility contractor placed the poles ata different location that put the poles in conflict with a new retaining wall. In these cases, theutility contractor had to move the new poles to the correct locations at no cost to TxDOT. Thegoal was to have poles at least 5 feet away from the excavation for any retaining wall because theutility owner required bracing for any excavation closer to 5 feet from an existing pole.A few poles were in conflict with various project features, such as driveways, culverts, anddrainage ditches. Each conflict was different and involved a different resolution strategy.The district experienced a few, mostly minor, issues with communication facilities. In somecases, the issue was existing underground communication lines being too shallow, which putthem in conflict with highway features or other utility facilities being relocated. In one case, itbecame necessary to postpone the relocation of several communication lines until the relocationof a gas line was complete. In other cases, overhead communication lines could not be relocateduntil the electric utility owner installed new poles to facilitate the relocation. Some delays in therelocation of communication lines also happened because the highway contractor had not yetfinished installing poles for traffic signals.For joint-bid relocations, the construction manager found the RFI process to be too slow (foreffective utility coordination purposes) and found it be more expedited to coordinate with theutility contractor directly to anticipate issues. Weekly meetings helped them stay on top ofthings.Most joint-bid relocation issues were related to constructability of water main relocations. At onelocation, the contractor could not find the tie-in point to the existing line despite conductingmultiple test holes and slit trenches. It turned out the existing as-builts the utility owner hadprovided to its own consultant to design the relocation were incorrect (Figure 23). Thisconsultant did not conduct test holes to verify the X-Y-Z coordinates of the tie-in points.Furthermore, the utility owner nor its consultant requested TxDOT to conduct test holes. Inaddition, the utility investigation was QLB in the area where the water main was going to remainin place, but then it was QLD in the area where the water main was going to be relocated. As aresult, the utility consultant did not actually know where the tie-in point was. Instead, theconsultant added a commonly used note on the plans requiring the contractor to locate the 103
nearest joint prior to fabrication of each tie-in closure piece, effectively transferring the risk tothe highway contractor.Courtesy of the TxDOT. Figure 23. Issue with Water Main Tie-In Location.The research team has been involved with UCM implementations at all 25 TxDOT districts. Inseveral cases, districts reported similar problems during construction, where the highwaycontractor had considerable difficulty finding utility infrastructure that should have beendocumented during the design phase. A lesson learned is to always require or conduct test holesduring the design phase to confirm the X-Y-Z coordinates of critical components such as tie-inpoints.At another location that also involved a joint-bid relocation of the water main, the highwaycontractor proposed a jack and bore solution under an existing gas station driveway instead ofdigging an open trench as specified in the plans (Figure 24). The open trench excavation wouldhave been too deep and close to the right-of-way line, making the total cost of relocating thewater main too high, after accounting for shoring, removal on an existing box culvert, andremoval and replacement of an existing block retaining wall in the cost estimate. The boringcomponent would have been more expensive but would have resulted in net cost savings for theproject. Unfortunately, the water utility owner refused to pay for the boring component on thegrounds that boring was only at the convenience of the highway contractor and that acceptingthis cost would increase their monetary contribution. In the end, TxDOT approved thecontractorâs request and absorbed the cost associated with the boring. 104
Courtesy of the Texas A&M Transportation Institute. Figure 24. Boring Under Existing Gas Station Driveway.At several locations, the plans and specifications called for abandoning water lines. The waterutility owner had a specification for abandoning facilities in place. The specification includedgrouting as part of the construction method description, but the payment section did notspecifically say that grouting is a subsidiary item. The utility owner considered grouting to be asubsidiary item and refused to accept this cost.At the same intersection where the conflict with the existing tie-in point was identified, anotherconflict involved an existing sanitary sewer (Figure 25). The contractor discovered that the actualalignment of the sewer was more to the south (i.e., to the left in Figure 25) than what the projectplans showed, making the sanitary sewer in conflict with the piers for the proposed underpass. Inaddition, according to the plans, the sanitary sewer was supposed to be encased in a 30-in steelpipe under the existing right-of-way. However, the contractor did not find evidence of the casing.The utility investigation for the sanitary sewer was at QLB. A change order was necessary tocorrect the alignment of the sanitary sewer. 105
Courtesy of the TxDOT. Figure 25. Sanitary Sewer Crossing.Change OrdersA review of change orders for Segments 1 and 2 revealed the following: ⢠For Segment 1, the total number of change orders was 41, of which 25 (or 61 percent) were UR and 16 (or 39 percent) were NUR. For Segment 2, the total number of change orders was 64, of which 21 (or 33 percent) were UR and 43 (or 67 percent) were NUR. Segment 2 is finalizing construction, so it is possible that the total number of change orders (mainly NUR), will increase. It is significant that the total number of change orders for Segment 2 was higher, but the number of UR change orders was lower. Further, the percentage of UR change orders decreased dramatically for Segment 2 compared to Segment 1 (33 percent versus 61 percent, respectively). ⢠The total dollar amount associated with change orders for Segment 1 was $15.9 million, of which $7 million (or 44 percent) were UR and $8.9 million (or 39 percent) were NUR. For Segment 2, the total dollar amount associated with change orders was $5 million, of 106
which $1.5 million (or 29 percent) were UR and $3.5 million (or 71 percent) were NUR. The total dollar amount for change orders in Segment 2 was 69 percent lower than for Segment 1. This reduction is probably not reliable since final numbers are not yet available for Segment 2. However, the numbers for UR change orders are more reliable because most UR issues were addressed earlier during construction. For UR change orders, the total dollar amount associated with Segment 2 was 79 percent lower than for Segment 1. Readers should be aware that there is an element of uncertainty in this estimate because change orders often address multiple issues, making the isolation of any one issue quite difficult.Overall, the change order numbers show that the UCM implementation, adding utilitycoordination and inspection to the scope of the CEI contracts, and other strategies (such as usinga right-of-way clearing contract) had a positive impact on the management of utility issues bothprior to letting and during construction.VIRGINIAâHILLSBORO IMPROVEMENT PROJECTProject OverviewThe Town of Hillsboro, Virginia, undertook a 0.8 km (0.5-mi) project called ReThink9 (108).This project consisted of two roundabouts (one roundabout on either end of the project), raisedcrosswalks, sidewalks, a new municipal drinking water system, wastewater treatment facility,stormwater collection system, undergrounding all overhead utility lines, and dark-sky-compliantstreetlamps (Figure 26, Figure 27). The project was completed in May 2021.The purpose of theproject was to relieve congestion and improve traffic flow while enhancing safety for motoristsand pedestrians. Route 9 is one of the regionâs busiest commuter and tourist travel routes. Theproject was first proposed to mitigate congestion along the Route 9 corridor. However, thetownâs water source was determined to be unsafe and its distribution system under Route 9 inneed of replacement. Failing and inadequate private septic systems also posed an environmentalthreat. Addressing all traffic and infrastructure components simultaneously resulted in asignificant reduction in the duration of impacts to traffic, residents, and businesses duringconstruction. 107
OpenStreetMap© (https://www.openstreetmap.org/copyright) Figure 26. ReThink9 Project in Hillsboro, Virginia. By DanX - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=107090222 Figure 27. Hillsboro, Virginia, After Project Completion. 108
The estimated construction cost was $12 million. However, bids came in at more than $20million, which the town could not afford. The designers then changed the sequence ofconstruction and prepared an updated maintenance of traffic (MOT) plan, lowering theconstruction schedule from 31 to 14 months. The original project included daily lane closures butwas modified to include full two-lane closures. The resulting lane closure schedule was asfollows: ⢠The roundabouts were built first. During this period, two-way traffic was allowed on Route 9. ⢠After the roundabouts were operational, one lane was open for eastbound traffic from 4AM to 9:30AM on weekdays. From 2PM on Friday to 6PM on Sunday, one lane was open for westbound traffic. After 6PM on Sunday, one lane was open for eastbound traffic until 9:30AM the following morning. ⢠The contractor could also close both lanes completely, without exceeding 60 days in total, in blocks of five days (minimum) and 30 days (maximum). In practice the contractor established two-lane closures in 600â1200 ft increments.The MOT was revised in April 2020 to include additional local and regional detours, which weremade possible during the COVID-19 pandemic.With these modifications, the estimated cost decreased to about $15 million. The winning bidwas $14.3 million. The Town of Hillsboro worked with VDOT to develop and deliver theproject. VDOT hired a prime consultant to conduct preliminary engineering and detailed designwork. This consultant was retained to provide construction management services. Asubconsultant provided utility coordination services all the way from preliminary engineering toconstruction. The scope of work for this subconsultant included working closely with allstakeholders to develop a multitask sequence of utility work activities in conjunction with theroadway schedule.Management of UtilitiesOne third of the project cost (or $5 million) was spent on utility and stormwater infrastructure,including 16,500 ft of communication conduits, 11,500 ft of electric conduits, new sanitarysewer and laterals, 6,000 of stormwater drainage pipes, 100 stormwater structures, and utilityvaults and manholes. The project included strategies to build utility systems in a narrowroadway, utility coordination for relocation work, and close coordination for consecutive andconcurrent relocation work. It also included preparation of utility as-builts using RFID devices.VDOT normally relocates utility facilities prior to letting. In this project, utility facilities wererelocated during construction to reduce impacts to the town. The contractor used the same MOTfor utility construction and roadway construction. In practice, construction staging involved asignificant amount of coordination between the contractor and each utility owner involved. Thiscoordination included temporary poles, which enabled construction of the roundabouts, thenstaged construction of the communication duct bank, running communication cables through theduct bank, removing old overhead cables, and removing existing poles, while the contractor wasalso working on drainage and roadway features. Once two-lane closures started, the pace of theconstruction quickened, including both roadway and utility relocation work. The temporary poles 109
that facilitated the construction of the roundabouts cost about $100,000, but officials concludedthat this expense was worth the investment.Upgrading the electric distribution system included a strategy to upgrade electrical meters andpanels at residential homes because many of these components were not up to code. The townmanaged this part of the project through a separate contractor in coordination with propertyowners and the electric utility provider.Use of RFID MarkersAs mentioned previously, VDOT started the RFID program to mark newly installed utilityinstallations to reduce the level of uncertainty with respect to these facilities and, morespecifically, as a damage prevention strategy. The current protocol at VDOT enables thecollection of X-Y-Z data at pre-specified intervals, enabling managers to generate an inventoryof those facilities. For the Hillsboro project, it was of interest to document X-Y coordinates, butnot necessarily elevations because roadway and utility work occurred simultaneously. For otherprojects in which utility relocation occur prior to letting, documenting elevations is critical.RFID readers cannot detect tags beyond 1.8 m (6 ft). As a result, VDOT installed RFID markerballs at 0.9â1.2 m (3â4 ft) deep, directly above the utility facility of interest. After completingthe backfill operation, a locator found the balls and captured their X-Y coordinates. Thehorizontal positional accuracy of the GNSS antenna was about 15 cm (6 inches). After gatheringthe information in the field, VDOT generated as-built polylines that provided a visualrepresentation of the utility alignments and prepared as-built PDF files containing plan andprofile information along with RFID marker locations and attribute data.Change OrdersThe only UR change orders were related to concrete in the duct banks. At some locations, thecontractor found big boulders that had to be removed, resulting in more concrete than what hadoriginally been estimated. At other locations, particularly around manholes, the contractorexcavated more than what was necessary, but the specifications did not require the contractor tohave more control over the duct bank cross section. After connecting the duct bank to themanholes, the contractor poured concrete to encase the duct bank around the connections, but thetotal volume of concrete used exceeded the original estimate. A lesson learned was to have theamount of concrete as a subsidiary item to the construction of manholes or, alternatively, as alump sum item.As a direct result of the MOT plan based on full road closures, utility relocation costs were lowerthan what had been estimated. In one case, the actual cost was almost $300,000 less than theoriginal estimate. In another case, the actual cost was $26,000 less than the original estimate. 110
