ACTT Workshop - Project Pegasus
September 9-11, 2003
- Table of Contents
- Chapter 1 - ACTT Background & Purpose
- Chapter 2 - Project Details
- Chapter 3 - TxDOT Workshop Meeting Details
- Chapter 4 - Next Steps
- Appendix A
- Appendix B
- Appendix C
Accelerated Construction Technology Transfer (ACTT) is a strategic process that identifies innovative techniques and technologies to reduce construction time on major highway projects while enhancing safety and improving quality. In September 2003, the Texas Department of Transportation (TxDOT) hosted a two-day workshop that applied ACTT principles and practices to the real-life case of "Project Pegasus," a major reconstruction of downtown Dallas traffic arteries now in the planning phases.
The workshop, which was held September 9-11 in Dallas, Texas, brought together almost 100 attendees from 19 states, including Washington, DC. Its purpose was twofold: to draw on the expertise of participants to help generate specific, practical recommendations for the ongoing development of Dallas' Project Pegasus; and to demonstrate for attendees how the ACTT process works in a real-life scenario so that they could apply ACTT in their own agencies. The key element of the workshop was the brainstorming session, which brought together experts from across the country with their local counterparts to search for methods and measures that would help TxDOT achieve its chief project objectives, namely minimizing construction time and traffic delays.
Project Pegasus consists of total reconstruction of the IH 30/IH 35E interchange - locally known as the "Mixmaster" - as well as other portions of both highways. The project will involve some 11 miles of roadway and over 99 entrance/exit ramps; moreover, the roads to be rebuilt are crossed by busy freight and commuter rail lines, and wind their way through and near historic buildings, hospitals, public parks, and flood-control levees. Because neither IH 30 nor IH 35E has been substantially improved since their original construction in the early 1960s, the redesign of the corridors will necessarily be dramatic in order to comply with current safety requirements and traffic-management guidelines. Another challenge presented by the project is handling the hundreds of thousands of vehicles that travel through the Mixmaster interchange each day. These are precisely the issues that ACTT was developed to confront, making Project Pegasus a natural choice as the topic for a national ACTT workshop.
Opening the workshop on September 9 were three officials representing TxDOT: Robert Nichols of the Texas Transportation Commission, Dallas district engineer Bob Brown, and the city's interim director of transportation planning and development Brian Barth. Following their remarks, the Chair of TRB A5T60, Don Lucas, posed the question "Why ACTT? Why Now?" before bringing on several TxDOT representatives to give an overview of Project Pegasus.
Over the course of the following day and a half, participants broke into nine "Skill Set" teams to examine how ACTT methods could be implemented to accelerate various aspects of the project. Once the Skill Set teams had developed lists of ideas, workshop participants began intermingling so that members could consult with experts from other Skill Sets. As the workshop progressed, each team completed report forms summarizing their ideas and recommendations (included as Appendix C), and also narrowed the results of their brainstorming and consultation down to a list of five to seven "priority" recommendations. These lists were then presented by each Skill Set team to the entire conference.
The workshop Skill Sets selected by TxDOT prior to the start of the workshop were: Environment; Geotechnical/Materials/Accelerated Testing; Structures; Right-of-Way/Utilities/Railroad; Innovative Financing and Contracting; Roadway/Geometrics; Traffic Engineering/Safety/ITS/Worker Health; Construction; and Long-Life Pavements/Maintenance. Each Skill Set team focused on how the ACTT process applied to the specific concerns of their area of expertise while collectively, the teams searched for methods/measures to help TxDOT achieve its goals of maintaining traffic with minimal disruption, accommodating regional/national/international events, providing access to emergency facilities, reducing construction time from 7 to 4 years, and maintaining a safe work zone.
To help TxDOT achieve its project goals, the teams offered the following recommendations, many of which were deemed viable and will be pursued, according to TxDOT Dallas District management:
- Consider tree "buffer" to mitigate Section 4(f) impact
- Coordinate timing of Pegasus with that of other Dallas-area roadway projects
- Allow time in project schedule to deal with historic-property issues
- Develop contingency plans for contaminated soil/groundwater
- Noise study still needed
- Check for contaminated soil before design and construction phases
- Consider future needs, geometry, etc., when looking at retaining-wall options
- Make aesthetic-related decisions early in design phase
- Dallas has problematic soils; address stabilization options early
- Prepare structure development report
- Call for contractor bids when design plans 30% complete
- Prefab as much as possible
- Consider prefab, temporary, reusable bridges during construction
- Initial cost estimates in this category were probably too low
- Outsource land acquisition
- Hire one utility consultant to coordinate with all utilities
- Determine staging-area needs (e.g., hazmat, pavement recycling) early on
- Use new electro-resistivity technology for SUE investigation
Long Life Pavement Design
- Long-term warranties are needed
- Use CRC with 4"-5" asphalt overlay
- Maximize use of recycled concrete
- On-site concrete and asphalt plants if possible
- Use ITS and timed closures to divert traffic
- Consider joint use agreements with city
- Establish tolls and managed lanes
- In procurement, look at parameters beyond lowest-bid
- Single contract is the best solution
- Delegate authority to single TxDOT project management team
- Build or improve frontage roads early
- Route all utilities through a single conduit
- Use recycled pavement material
- Implement HOV restrictions and truck diversions during construction
- Make worker safety and public safety a priority during planning
- Maintain ITS during construction
- Use local media and Web to provide traveler information
- Coordinate incident management strategies with local EMS, fire, police
- Find alternate routes to allow total closure of IH 30
- Expand bus service and promote carpooling during project
- Use Design-Build with one large contract
- Involve construction industry early to minimize redesign
- 10-day turnaround on review/approval process
- Identify pavement-life goals; let designer and contractor find best solution
- Factor in time and expense of preparatory projects such as utility relocation
With the workshop now completed, it now remains for TxDOT to sift through the various workshop ideas/recommendations and decide which ideas should be implemented in future planning, design, and construction phases of Project Pegasus. Six-month and one-year meetings will be coordinated with TxDOT to evaluate the long-term benefits of the workshop and the extent of the implementation of its recommendations.
Chapter 1 - ACTT Background & Purpose
In recent years, communities have witnessed a tremendous increase in highway construction activity, addressing the need to preserve or rebuild our highway infrastructure. Although highway construction is unavoidable, unnecessarily long construction time should be avoided because the process is costly, exposes construction workers to traffic, and subjects motorists to substandard conditions. Accelerated Construction Technology Transfer (ACTT) can help to minimize traffic delays and community disruptions by reducing cost and construction time, while improving construction quality and workzone safety.
ACTT is a strategic process that uses innovative technologies and techniques to reduce construction time on major highway projects while improving construction quality and workzone safety. A complete Accelerated Construction approach involves the evaluation of all aspects of highway projects from planning and development to design and construction within a highway corridor. Successfully deploying ACTT for the benefit of the traveling public requires a thorough examination of all facets of highway corridors, with the objective of improving safety, optimizing cost effectiveness, and minimizing adverse impacts.
Recommendations outlined in Special Report 249 from the Transportation Research Board (TRB) called for the creation of a forum to promote accelerated construction in the highway infrastructure. Based on this recommendation, TRB Task Force A5T60 was formed in 1999 with the following objectives:
- Remove barriers to innovation;
- Advocate continuous quality improvement and positive change;
- Enhance safety and mobility;
- Encourage the development of beneficial strategies; and
- Create a framework for evaluating proposed innovations.
Fully supporting the task force's mission and objectives, the Federal Highway Administration (FHWA) and the Technology Implementation Group (TIG) of the American Associations of State Transportation Officials (AASHTO) joined the task force's outreach effort. This resulted in the formation of a national resource pool known as the "National Skill Sets Council" and completion of two ACTT pilot workshops. With successful completion of two ACTT pilot workshops (one in Indiana and the other in Pennsylvania), A5T60 passed the concept off to TIG and the FHWA to continue the effort by conducting all future workshops.
In 2003, the ACTT Management Team, consisting of TIG and FHWA representatives, started implementing the ACTT program by sharing its workplan with State DOTs and soliciting their consideration of the concept on major highway projects by hosting an ACTT workshop. The Texas Department of Transportation (TxDOT) selected "Project Pegasus" as the focus of the workshop. The rationales for choosing this particular project, which involves the reconstruction of IH 30 and IH 35E near downtown Dallas, include:
- The corridor was already due for major reconstruction and rehabilitation;
- Proximity to the major employment centers and high traffic volumes of downtown Dallas meant there was a need to accelerate construction;
- The project is still in the planning process and has not received environmental clearances; and
- TxDOT is open to innovation and willing to consider and apply new concepts.
1.2 Purpose of ACTT
The purpose of an ACTT Workshop is to explore innovative ways that highway corridors could be brought to full service more quickly and safely, and with fewer adverse impacts on the traveling public. The Project Pegasus workshop brought a multidisciplinary national team of transportation professionals together with their local counterparts. Over the course of two days, the workshop participants explored innovative ways to accelerate the construction of Project Pegasus. The workshop included plenary sessions, breakout sessions, skill set interaction, closing remarks, and a follow-up action plan.
Chapter 2 - Project Details
2.1 Corridor Description
Project Pegasus is intended to totally re-design and restore mobility to the two major Interstate Highways directly serving downtown Dallas. The study area, shown in Figure 1, covers IH 30 from Sylvan to IH 45 and IH 35E from Eighth Street to Empire Central (north of SH 183). The interchange of IH 30 and IH 35E is locally known as the "Mixmaster" and the depressed portion of IH 30 south of downtown is known as the "Canyon." The section of IH 35E from the Mixmaster to SH 183 is referred to as "Lower Stemmons."
Figure 1. Project Location
The total project, scheduled for completion over 36 months, involves approximately 11 miles of roadway and over 99 existing entrance/exit ramps. Future freeway volumes range from 200,000 to 320,000 vehicles per day. The design widens both IH 30 and IH 35E and the interchange, and includes reversible HOV/Managed lanes. Among the challenges facing the project are: high traffic volumes, NAFTA-related traffic, the problem of balancing transportation needs with local access, extremely constrained right-of-way, parklands, historic buildings, meeting current design standards, potential construction impacts, affordability, and integrating urban design. The project team is currently at work on the schematics and environmental assessment, with an eye on development alternatives, traffic considerations, and extensive public and agency input.
2.2 ACTT Goals
It was TxDOT's hope that the ACTT approach could help reduce construction time while giving Dallas motorists a high-quality product. TxDOT established seven goals for ACTT Workshop participants:
- Maintain traffic with minimal disruption
- Accommodate regional/national/international events
- Provide access to emergency facilities and businesses
- Reduce construction time to 4 years
- Maintain a safe work zone
- Minimize the delays introduced by right-of-way, utilities, and railroad
- Incorporate context sensitive design
2.3 Project Pegasus Objective and Goals
The primary objective of Project Pegasus is to relieve traffic congestion along IH 30, IH 35E, and throughout the Mixmaster interchange. The goals for the project include:
- Maximizing the vehicular capacity of the freeway system by integrating High Occupancy Vehicle (HOV) lanes, Intelligent Transportation Systems (ITS), Transportation Systems Management (TSM), and Travel Demand Management (TDM) elements into the design
- Minimizing the need for additional right-of-way
- Providing more reliable transportation facilities by decreasing congestion and travel times
- Improving interregional connections to existing and proposed roadways and transit facilities
- Enhancing travel and accessibility to downtown Dallas, major employment areas and activity centers within the corridor
- Maintaining bicycle and pedestrian access across the facilities
- Integrating urban design elements that reflect the character and location of the surrounding communities and
- Finding a solution that is both technically and financially feasible
2.4 Proposed Improvements
The general concept is for five to six lanes in each direction with one- or two-lane reversible HOV/Managed lanes in the median. A continuous frontage road system is also proposed along portions of the route to maintain access to adjacent properties. Estimated construction and right-of-way costs are approximately $750 million, as of May 2003. The following highlights the elements of the preferred design:
- Includes a continuous and reversible HOV/M lane system
- Adds one general-purpose travel lane in each direction in some areas
- Meets current design standards for freeway lanes and shoulder widths
- Eliminates left-hand merges and diverges
- Provides "lane continuity," so that drivers need not change lanes to stay on same freeway
- Eliminates inside merges on main lanes
- Includes direct connections in all directions in the IH 30/IH 35E interchange
- Eliminates the severe freeway weaving area between Spur 366 and DNT
- Provides continuous surface frontage roads along IH 30 and IH 35E
- Eliminates the current Collector-Distributor (C-D) roads adjacent to the Canyon main lanes
- Simplifies South Central Expressway interchange with IH 30
- Provides HOV/M lane access at Commerce Street and Medical Market Center
- Allows adequate horizontal and vertical clearance for bicycle and pedestrian crossings
- Incorporates aesthetic elements, landscaping and urban design treatments
- Provides 10-foot sidewalks on freeway cross-streets
- Accommodates bicycles in a shared lane by allowing 14-foot outside lane widths at cross streets over/under the freeway
- Includes ITS
2.5 Project Background
The IH 30 and IH 35E corridors were studied as part of the Major Transportation Investment Study (MTIS) conducted on the Trinity Parkway Corridor between 1996 and 1998. The purpose of the MTIS was to develop a solution to congestion in the IH 30 Canyon and IH 35E/IH 30 interchange near the Dallas Central Business District (CBD) and the Trinity River. The study - which extensively involved the public and public agencies - evaluated numerous travel modes, considered over 40 alternative approaches, and produced preliminary designs, traffic, hydraulic, and environmental analyses.
The final $1 billion recommendation included improvements to the existing interchange and interstates; HOV lanes; a new tollway; an extension to Spur 366; a light rail line; bicycle and pedestrian improvements; ITS; and employer trip reduction programs. Because no single agency would be responsible for designing and building all of the recommended improvements and many of the improvements have independent utility, they are being further developed by the appropriate agencies. Project Pegasus addresses the improvements to the Mixmaster and interstate highways, while incorporating HOV lanes, ITS, and bicycle and pedestrian elements in the corridor.
2.5.1 Project Challenges
Designed in the 1950s, IH 30 and IH 35E were built between 1958 and 1962. The current design of the freeway, service roads, ramps, and surface streets in the area contribute to the poor operation of the freeways and do not properly provide for today's major traffic demands. Forced lane changes, abrupt and unexpected merges, short weaves, and left-hand entrance/exits compound the problems. Additionally, the IH 30/IH 35E interchange does not include direct connections from eastbound IH 30 to southbound IH 35E and northbound IH 35E to westbound IH 30.
Additionally, the design standards for freeway and interstates have changed since the roadways were built. The roadways do not meet current design standards with regard to ramp acceleration and deceleration lengths, spacing of interchanges and ramps, vertical clearances, horizontal clearances, and sight distances.
Congestion in this area slows travel for many miles along other freeways feeding into downtown, such as IH 35E, IH 45, US 75, and IH 30. No significant improvements to roadway capacity have been implemented since these freeways were originally constructed. Several bottleneck removal projects have been implemented, which have provided only minor relief in traffic. The travel demand along the IH 30/IH 35E corridors is beyond the current capacity of the freeways. This is most evident in the morning and evening rush hours on weekdays, with heaviest traffic flows northbound and westbound in the morning hours, and southbound and eastbound in the evening hours. On average days, traffic on the freeways is congested for more than six hours daily, with average speeds of approximately 20 mph.
Figure 2. 2026 Daily Traffic Volumes
The redesign of IH 30 and IH 35E have provided numerous challenges to the design team, including:
- NAFTA Corridor & Truck Traffic - Heavy truck traffic on IH 35E is estimated to be over 10 percent of daily traffic volumes. Given daily volumes of 320,000 in some areas, this equates to over 32,000 trucks a day.
- Multiple Major Traffic Movements - There are five major interchanges within a very short distance - IH 30/IH 45, IH 30, IH 35E, IH 35E/Spur 366, and IH 35E/Dallas North Tollway (DNT). The weaving areas between the major movements conflict and influence traffic operations significantly.
- Balancing Transportation Needs with Local Access - There are 99 existing entrance and exit ramps within this 11-mile long project area. The primary purpose of the interstate system is national defense, not local access. Current interstate design standards for ramp spacing and weaving distances will not permit all of the existing entrance and exit ramps to remain in the new design.
- Constrained Right-of-Way - These corridors are highly developed and right-of-way is limited by development, railroads, and the Trinity River Levee system.
- Development - The property adjacent to the freeway is home to numerous large buildings and activity centers, including the Dallas Convention Center, Reunion Arena, American Airlines Center, Dallas Market Hall, InfoMart, World Trade Center, and seven hospitals.
- Railroads - Four active railroads cross IH 30 and IH 35E. The Union Pacific Transcontinental rail line crosses both IH 30 and IH 35E with 40 trains a day. The DART Light Rail crosses IH 30 and carries both the Blue and Red Line with 365 trains per weekday. The Trinity Railway Express Commuter Rail line crosses IH 35E near SH 183 and carries over 50 passenger trains per weekday and is an active freight line. Three of these bridges will require full reconstruction while maintaining rail operations.
- Trinity River Levee System - The levees are approximately 35 feet tall and provide flood protection to the City of Dallas. Both IH 30 and IH 35E cross over the top of the levees and then must drop to ground level to pass under the Houston Street Viaduct.
- Environmental Issues - There are four publicly owned city parks immediately adjacent to the interstates. In addition, several historic properties are adjacent to the freeways, including Farmers Market, Dealey Plaza Historic District, West End Historic District, and several other buildings eligible for listing on the National Register of Historic Places. The Houston Street Viaduct, which crosses over the Mixmaster area, was built in 1911 and is listed on the National Register of Historic Places. The openings of the bridge are 65 foot wide and constrain the width of the freeways as well as both the horizontal and vertical alignments (see Figure 3).
Figure 3. Houston Street Viaduct
- High Traffic Volumes - Current traffic volumes within the study area range from 127,000 to 286,000. Future traffic volumes on the freeway in 2026 are projected to be between 200,000 to 320,000 vehicles per day. These volumes assume the Trinity Parkway will be in place and carry 80,000 to 100,000 vehicles per day.
- Design Standards have Changed Since Roadways were Originally Built - The existing roadway does not meet current interstate design standards for such parameters as horizontal and vertical clearances, lane and shoulder widths, acceleration/deceleration lanes on ramps, ramp spacing, sight distances, inclusion of left-hand exits and entrances, lane continuity, signage, and the ability to provide for incident management.
- Access & Traffic Handling during Construction - With so many activity centers including downtown, major employers, and hospitals within the corridors, constructability and access have been an underlying concern.
- Affordability - TxDOT and this region are faced with a funding shortfall, and no funding source has been determined for the project. Having an economic and efficient design that has the support of the community will be vital to moving towards funding and construction.
- Urban Design - Project Pegasus is one of the first Dallas-area projects in which the TxDOT, from the very early stages of planning, has actively considered urban design and landscape treatments to complement and enhance the aesthetic quality of the freeway corridors.
2.5.2 Public and Agency Involvement
A large component of the project is public and agency involvement. In addition to a project newsletter, a website has been developed - (http://www.projectpegasus.org/). This site has more much information than can be contained in a single newsletter, such as the project history, maps, and summaries of meetings. It also allows the design alternatives to be posted in .pdf format, thereby facilitating public review. There are also fill-in forms on the website allowing visitors to e-mail comments, be added to the mailing list, or request a presentation.
Other public/agency involvement efforts include the establishment of a Project Coordination Work Group and a Community Work Group, which both meet on a regular basis. To inform businesses and property owners, information packets have been hand-delivered to business and property owners along the corridor. A portable project kiosk has also been used at public locations within the project study area to inform the public about the project's existence, purpose, need, and progress.
2.5.3 Design Development
The development of alternatives has occurred in three phases.
- In Phase 1 (November 2001 to May 2002), the study team developed conceptual alternatives. The alternatives were based on identified deficiencies and travel patterns in the study area, previous planning efforts, and public and agency input. Previous planning efforts include the Trinity Parkway Corridor MTIS recommendations for IH 30 and IH 35E.
- In Phase 2 (June 2002 to January 2003), having selected the most promising alternatives from Phase 1, the study team continued to develop these proposals to a higher level of detail - incorporating, as appropriate, comments and concerns from the public and study work groups.
- During Schematic Development (February 2003 to July 2003), the study team worked on refining the locally recommended design from Phase 2. This phase included the preparation of a detailed design schematic, design exception report, interstate access justification report, signing schematic, and environmental assessment.
The schematic design effort includes a detailed traffic analysis, signing schematic, Design Exception Report, Interstate Access Justification Report, and draft HOV/M operations plan.
2.5.4 Value Engineering
Prior to beginning the schematic design, a week-long Value Engineering workshop was held to review the project design. Value Engineering is a program to improve project quality, reduce project costs, foster innovation, eliminate unnecessary and costly design elements, and ensure efficient investments. Held in March 2003, the workshop was attended by representatives from TxDOT, FHWA, City of Dallas, Dallas County, North Texas Tollway Authority, North Central Texas Council of Governments, and Texas Transportation Institute. Sixteen geometric and 10 structural issues were analyzed. The overall design and traffic operation would be improved by the recommendations and could mean potential cost savings of 6.5 percent.
2.5.5 Environmental Documentation
Based on the schematic design, an Environmental Assessment and Section 4(f) Statement are being prepared to document social, economic, and environmental effects. Because the project corridor is heavily developed, little impact to the natural environment is anticipated. Major social, economic, and environmental issues include land use, access, park land, and historic properties. Awareness of these issues has helped the study team avoid and minimize impacts in most areas. In areas of impact, mitigation will be proposed.
2.5.6 Urban Design
The urban design component has also been initiated to enhance the transportation corridor environment from the perspectives of both motorists and the adjacent property owners. The Urban Design process involves ultimate "what if" items to be considered for future cost-shared community upgrade projects, such as signage, illumination, public art, landscaping, specialty pavement, community gateways, design of bridge structures, bridge column supports, and so forth.
In the IH 30 Canyon area, where the freeway is depressed, the concept of "lids" over the freeway to create deck parks has also been suggested. This element could be built later, after reconstruction of the freeway, but this option requires that the retaining walls be designed to support a future deck. The City of Dallas is evaluating costs and funding opportunities to finance the decks. The implementation of urban design elements will require cost sharing between the City of Dallas and TxDOT.
2.6 Project Status
- The schematic was sent to TxDOT Design Division on July 9, 2003; it has subsequently been forwarded to FHWA for concurrent review.
- The design exception report, interstate access justification report, and signing schematic were sent to TxDOT Design Division on August 20, 2003.
- The draft EA and Section 4(f) Statement are approximately 85 percent complete.
Chapter 3 - TxDOT Workshop Meeting Details
TxDOT hosted an ACTT Workshop for Project Pegasus on September 9-11, 2003, in Dallas, Texas. Almost 100 people attended from 19 states, including the District of Columbia. Appendix A includes a list of the attendees.
In a pre-workshop meeting with the ACTT Management Team, TxDOT selected the following skill set areas for the Project Pegasus ACTT Workshop:
- Geotechnical/Materials/Accelerated Testing
- Right-of-Way/Utilities/Railroad Coordination
- Innovative Financing
- Innovative Contracting
- Roadway/Geometric Design
- Traffic Engineering/Safety/ITS
- Long Life Pavements/Maintenance
The Innovating Contracting and Innovative Finance sets were combined. A description of each of these skill sets is included in Appendix B.
3.1 Opening Session
The workshop began with opening remarks from three TxDOT officials:
- Commissioner Robert Nichols, Texas Transportation Commission
- Bob Brown, Interim Dallas District Engineer
- Brian Barth, Interim Dallas Director of Transportation Planning and Development
Following these speakers to the podium was Don Lucas of the Heritage Group and Chair of TRB A5T60, who addressed the question: "Why ACTT? Why Now?" After Don's presentation, all workshop participants had an opportunity to introduce themselves. Attendees were next given a brief overview of Project Pegasus by Tim Nesbitt, TxDOT, Project Manager; Sandy Wesch-Schulze, Carter & Burgess, Consultant Team Project Manager, and Richard Mason, TxDOT Deputy Project Manager.
Stu Anderson, Texas A&M University, served as the workshop moderator. He reviewed the agenda and work outline for the next two days. Upon conclusion of the formal Opening Session, the forum broke for a bus tour of the project.
3.2 Workshop Process and Recommendations
In the next day-and-a-half, the Skill Set groups met to discuss various aspects of the project and methods for accelerating project implementation. After allowing time for each Skill Set group to discuss issues and begin forming ideas, participants intermingled to further discuss and consult with other groups on strategies and concepts.
Each group completed reporting forms, which are included in this report as Appendix C. Each Skill Set group was also asked to rank five to seven ideas in order of top priority, and to make a presentation to the whole conference. The following are the top recommendations relating to each Skill Set.
The Environmental Skill Set group discussed the environmental constraints, opportunities, and pending issues for the project.
- There will be a Section 4(f) impact at Stemmons Park. The design needs to include avoidance and/or minimization as well as mitigation. Mitigation could include replanting Live Oak trees or purchasing additional land just south of the park and donating the land to the city.
- The timing of several projects (Project Pegasus, Trinity Parkway, and others such as the Southern Gateway) need to be closely coordinated. Could the tolls on the Trinity Parkway be reduced while IH 30 and IH 35E are under construction? The Trinity Parkway has a proposed opening date of March 2012, which could affect the start date on Pegasus. The Southern Gateway has a start date on 2015.
- There are numerous historic properties. Coordination time must be built into the project schedule. A new bridge over the Houston Street Viaduct cannot be constructed because of historical requirements.
- A hazardous materials report has been prepared. Mitigation and contingency plans for contaminated soils and groundwater are yet to be developed. New technologies for quantifying subsurface contamination in place must be investigated.
- Context-sensitive design needs to be linked to design, right-of-way, construction, and financing.
- It might be possible to open up Old Mill Creek. This needs to be discussed with the City of Dallas. This could provide an opportunity for water quality and stream restorations. The option of opening up Old Mill Creek should be explored only if there is a need to mitigate for water resources due to adverse impacts from the proposed project.
- IH 30 Canyon decks could be used as staging area for construction.
Other Pending Issues
- Socio-economic impacts are semi-resolved. There appear to be no environmental justice issues.
- Noise study is needed to determine impacts and need for mitigation.
- Multiple nationwide permits may be needed. It remains to be determined whether pre-construction notification will be required.
This Skill Set group made recommendations in four areas to accelerate construction while maintaining or improving the project.
- Conduct soil testing prior to environmental clearance. Look for contaminated soil and try to find out before design but definitely before construction.
- Obtain geotechnical information and borings early to help to make design decisions.
- Design-build will make the information above even more critical (reduced risk = reduced price).
- During the selection of retaining wall types, consider the phasing of work, future needs, existing ground geometry, subsurface conditions, and impacts of wall treatments on design and construction.
- Make decisions on aesthetics early in design and coordination details.
- Coordinate with geotechnical team early and often.
- Dallas has problematic soils for pavement sub grades, including expansive clays and high sulfate content soils.
- Conduct a detailed geotechnical investigation including sulfate soil determination.
- Try to stabilize soils in place.
- Stabilization of thick sub-grade layers could be done using deep soil mixing techniques and massive soil stabilization.
- Sulfate soil stabilization could be done by engineering solution with existing stabilization agents (lime and cement) or the use of new stabilizing agents.
- Save time and stay out
- Look at utilities early
- Consider 24/7 construction
- Train ahead of time to increase efficiency, use techniques, and methods on other projects first
The top five recommendations from the Structures Skill Set were: prepare a structure development report; call for bids on contract at 30 percent complete; use prefabricated construction; select construction techniques that minimize traffic impacts; employ temporary bridges.
Structures Development Report
- Group structure types to try to create an "assembly line" system and maximize standardization. Types could include overpass, mainline, low, medium, high, and retaining walls
- Use high-performance materials
- Look at corrosion-protection strategy
- Maximize use of standardized and prefabricated structures / elements
- Determine foundation requirements early
- Incorporate preformed lightweight fill
Bid Contract at 30 percent Bridge Plans
- Designer prepares plans to 30% with quantities +/-20 percent; then advertises and selects contractor
- Contractor works with designer and owner to complete plans and construct project
- Implementation with single or multiple contracts to allow flexibility
- Prefab as much as possible to minimize traffic disruption during construction
- Pre-cast substructure: abutments, bents, columns. Post-tension elements together for continuity
- Pre-cast superstructure: slab, girders, segmental boxes or prefabricated superstructure units
- Incremental launching (Canyon & TRE line)
- Balanced cantilever will reduce crane usage
- Use prefab modular bridges for temporary structures or develop standardized modular bridges.
- Bridges can be reusable; multiple-use bridges reduce cost, and cost is amortized over multiple projects. When project is completed, give bridge to county or city for bridge replacement or stockpile for future emergency or security use.
The Right-of-way/Utility/Railroad Skill Set group believes the right-of-way costs were underestimated. TxDOT should assume $75 million for land, $300 million for utilities, and $15 million for railroad relocation.
It was recommended that TxDOT outsource the land acquisition, relocation assistance, and negotiation of access. Also, one utility consultant should be hired to design, inspect, coordinate, communicate, and cooperate with all utilities. The actual relocation of utilities should be included as part of the highway construction contract and the railroad force account should be used.
In order to start the right-of-way acquisition process and the relocation of utilities, the Right-of-Way Department needs as much information as soon as possible. This should include the schedule as well as the need and location of proposed staging areas (e.g., hazmat, pavement recycling, construction materials). The State currently owns property at US 75 at Carroll Avenue, which could be used as a staging area. Properties that will be difficult to relocate, such as the liquor stores and SPCA, should be acquired as early as possible. The design consultant needs to coordinate early with TxDOT and the railroads.
Other right-of-way and utility issues that should be considered during design are the inclusion of fire hydrant for CD roads and elevated roadways in case water is needed in emergency situations; control of access; 96" sewer line down median of IH 35E (north section); and utilities affected by railroad relocation. The skill set also suggested using a new technology for SUE investigation that relies on electro-resistivity to show hazmat plumes, conduits, and soil strata.
There were also other legal and procedural changes recommended to speed the process; it was recognized that some legislation might be necessary to allow these changes to happen. These recommendations included quick action, the delegation of more authority to Districts, risk management, establishment of criteria to designate when the number of utilities in the corridor had reached the allowable limit, and the consideration of utilities as part of the transportation facility.
3.2.5 Long Life Pavement Design
This Skill Set group looked at five major areas and made several recommendations to accelerate construction while maintaining or improving the design of the pavement.
- Long term warranties are needed to assure performance
- Design-build is ideal for this type of guarantee
- Should be performance based
- Include incentives in long-term warranties (10 years)
- Performance includes such variables as smoothness, friction, noise, cracking, rutting, etc., and should be based on TxDOT deterioration curves
- Recommendations for increased strength/durability
- CRC with 4" - 5" asphalt surface
- Concrete temperature and moisture variations reduced by asphalt overlay
- Asphalt temperature is lowered and rutting reduced when placed on top of concrete
- Surface renewal is easier and less intrusive to traffic
- Make maximum use of recycled concrete as aggregate base or retaining wall backfill
- Assure long term performance by improving general material specifications so that only premium materials are allowed
Construction Staging Areas
- Promote on-site production or locate production close by to speed up construction; consider on-site concrete and asphalt plants
- Reduces haul time
- Reduced traffic congestion due to construction vehicle ingress/egress
- Consider total closure
- Utilize ITS to divert traffic
- Consider weekend closure
- Close to non-HOV traffic
- Close one direction of traffic
3.2.6 Innovative Contracting/Financing
This Skill Set working group divided their discussion into five areas: financing, preconstruction, procurement options, delivery, and management.
- Joint use/joint development agreement such as decks/lids for income
- Tolls and managed lanes
- Other federal funds (HUD, USACE, EPA)
- Credit assistance for developers and cities who want to finance part of federal-aid projects (TIFIA, SIBs, Section 129)
- Risk Management: Put responsibilities to the person best suited to handle the risk
- Consider special prequalification, thus ensuring contract has specialized expertise to perform work
- Multi-parameter evaluation (i.e., not just low bid)
- Incentives/disincentives for minimizing traffic disruption such as lane rental; lane assessment for not opening lanes during travel time; development of a traffic control plan by contractor
- Utilities (allow third party agreements; put utility coordination into construction contract; consider outside utility coordinator contract)
- Warranties (pavement, use in conjunction with design-build)
- Single contract is the best solution
- Preferred approach would be single-source design-build
- If design build not feasible, may need to go with hybrid approach: construction management with at-risk general contractor
- Single TxDOT Project Management Team with possible assistance from consultants. Delegate authority to project team
- Performance specifications: contractor-developed traffic control plans
- Critical path schedule; create cash flow curve
- Bid escrow
- Change order plans (preset pricing)
- Lower retainage and bonding requirements for contractors
This group did not see any major problems with the schematic design. However, to reduce cost and construction time, the group recommended that TxDOT consider the following:
Reduce Vertical Clearance
- Consider vertical clearance of less then 16' 6" in some places
- This can reduce cost
- Minimize other design exceptions caused by maintaining 16' 6" clearance
- Makes drainage easier in some cases
- Reduces retaining wall heights
- Improve the mainlane grades
- Potentially reduces earthwork
- Build or improve the frontage roads early so they can be used as temporary mainlanes during construction
- Best if built first
- Need investigation of and coordination with City of Dallas on the 96" sewer along IH 35E north section
- Have a single utility conduit for all utilities
- Assign a utility relocation project manager/coordinator
- Use recycle material, crushed base or overlay
- Cover up existing pavement and use as part of base
- Best used where horizontal location will remain the same
- Reduce pavement criteria for the HOV section because of lack of trucks
Maintenance of Traffic during Construction
- Use HOV restrictions
- Encourage truck diversions
- Consider full closure for longer periods (weekends, etc.)
- Include media efforts to disperse information and conduct surveys
The Traffic/ITS/Safety skill set identified six types of strategies to accelerate construction.
Maximize Safety throughout Project
- Develop a comprehensive Safety and Health Plan for worker and traffic safety; traffic safety should include both public traffic and construction traffic
- Include a contract for wrap-up insurance for all parties
- Ensure worker safety by incorporating appropriate guidelines in project development documents, training workers, and adding an incentive for positive safety performance
- Ensure public traffic safety by providing additional traffic enforcement within construction zone, developing an education campaign with public service announcements, and using gawk screens
- Traffic safety in construction should include require coordinated work-zone plans to evolve with design, assure adequate access to/from work zones
Maintain ITS during Construction
- Coordinate early on utilities and fiber - try to install early or retain existing system
- Use high mast CCTV
- Consider "portable" ITS system at key locations if early deployment of ITS is not possible
- Identify and use other key corridors and arterials
Provide Traveler Information
- Use advanced Highway Advisory Radio
- Continually coordinate with media (TV, Newspaper, Internet)
- Assure 511 information-line implementation with dedicated service for project
- Develop web site with real-time information
- Consider event plans as examples of training and information (i.e., State Fair, Market Shows)
- Coordinate with AAA and other travel advisors such as MAPSCO and Mapquest
- Coordinate with trucking and freight companies
- Inform construction partners
Provide Coordinated Incident Management
- Identify a dedicated incident management coordinator
- Seek one-call response for investigation
- Obtain local stakeholder input (i.e., EMS, Fire, Police, hospitals)
- Place signs and markers along the corridor for easy identification of incident locations (by the construction date, GPS cell phones should be more commonplace)
- Disseminate traffic control plan to stakeholders and affected parties
- PIO/team should manage information
- Define the contractor's role in incident management
- Dedicate freeway service patrol to corridor
- Dedicate police/fire response within corridor
- Push for Dallas County Sheriff Patrol to provide incident management for corridor
- Write into the contract a set number of dedicated personnel to be hired from local police, fire, and towing services
- Encourage regional incident management training
- Push E-911 wireless
Provide Effective Traffic Control
- Build frontage roads first to use as alternate routes during construction
- Fast track Trinity Parkway and Woodall Rodgers (Spur 366) extension
- Encourage traffic to use IH 35W or IH 20 and IH 635 as alternate routes, especially for traffic not destined for Dallas; coordinate with other TxDOT Districts
- Investigate alternate routes to allow IH 30 to be closed; review scheduling and phasing to provide alternate routes
- Maintain a minimum number of lanes
- Investigate targeted night time and weekend closures by segment
- Utilize traffic analyses for contracting and financing with lane rentals and lane assessment
- Review past special events such as World Cup, State Fair, and Trinity Fest
Manage the Demand
- Explore options for increasing transit usage such as Bus Rapid Transit or additional express bus service; include support transportation by providing short-term vehicle rental and shuttles
- Provide subsidies
- Encourage employer programs such as flex-time
- Encourage carpooling and vanpooling
- Provide multi-modal connections and additional park-and-ride lots
- Maintain function of IH 30 and IH 35E HOV lanes to increase their usage
- Use extended temporary closures on weekends
- Use Design-Build with one large contract
- If Design-Build is not possible, consider prequalification of contractors
- Allow the contractor to develop traffic control plan
- Involve the construction industry early in the design to minimize re-design
- Hire a PEF or contractor to perform a constructability analysis
- Have one project manager and a senior management team (cabinet) for advising the manager
- Give review/approval authority
- Provide a 10-day turnaround on comments and reviews
- Develop a process for resolving disputes
- Develop QA/QC processes
- Use electronic document control
- Use CPM scheduling with bi-weekly updates
Construct Preparatory Projects
- Frontage roads
- Utility relocations
- Access improvement that can be addressed
- Alternate route improvements
- Reconstruction of bridges
- High Mast lighting
- Hazardous material remediation
Maximize Contractor Control
- "Loosen" specifications
- Give flexibility in material usage
- Flexibility in the traffic control plan
- More control of utilities relocation
- Staging areas
- Nested design-build gives contractor more opportunities to solve problems
- Alternate bid items
Evaluate All Traffic Minimization Alternatives
- Detours and temporary use of Trinity Corridor
- Alternate routes
- Non-motorized considerations for pedestrians and bicycles
- Remove or restrict trucks
- Close sections of the roadways for period of time
- Build the Trinity project first
- Close freeways directionally
Chapter 4 - Next Steps
TxDOT will be evaluating the recommendations from each of the Skill Sets to determine which ideas or suggestions should be adopted for use during the remainder of the planning, design, and construction phases of Project Pegasus.
Additionally, six-month and one-year meetings will be coordinated with the TxDOT to assess the long-term benefits of the workshop and the extent of the implementation of its recommendations.