U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
The North Forest Boundary project is located on existing SR 179 from milepost 310.5 to 313.8 (junction with SR 89A), which includes a portion of SR 89A from milepost 374.0 to 374.2, in Sedona (figure 2).
Figure 2. SR 179 project boundary.
The existing SR 179 is functionally classified as an urban principal arterial and is a two-lane undivided highway with no shoulders or dirt shoulders at some locations. Figure 3 shows the existing SR 179 looking north at Meadowlark Drive. Safety concerns coupled with the lack of roadway capacity to accommodate multimodal use by motorists, pedestrians, bicyclists, and an overwhelming amount of visitor traffic prompted ADOT to address the deficiencies of the entire 9-mile corridor. In response to the community’s need and to conserve the unique scenic nature of the area, ADOT initiated a comprehensive, two-phase project between the village of Oak Creek and the junction of SR 89A.
The North Forest Boundary–Sedona project is the second phase of the overall project, which covers SR 179 from milepost 310.5 to 313.8 (junction of SR 89A) and includes a portion of SR 89A from milepost 374.0 to 374.2.
Figure 3. Existing SR 179 looking north at Meadowlark Drive.
The second phase of the Sedona project consisted of widening the existing undivided two-lane highway to a two-lane divided highway with raised median. The northbound and southbound lanes were constructed with an 8-foot (ft) paved shoulder along with several dedicated right and left turn lanes to keep the through-lane traffic moving. Six roundabouts were constructed at the major intersections (two two-lane and four single-lane). Two local crossroads were realigned to consolidate access points at the Arrow and Morgan roundabouts. Curbs and gutters were established along the entire project.
A designated, signed, and striped 5-ft-wide bike lane was installed in the 8-ft shoulders. Sidewalks and/or pedestrian pathways with dedicated transit stops were established along the entire corridor. Many parts of the old alignment were graded to create a more level highway at this mountainous 4,200-ft elevation. The new roadway was surfaced with rubberized asphalt. The 2003 average daily traffic (ADT) for the SR 179 ranged from 14,000 at the village of Oak Creek to 21,000 at the junction of SR 89A. Truck traffic is estimated at 4.5 percent of the total daily traffic during the weekdays and about 2 percent during the weekends.
ADOT included many innovative but proven technologies and techniques to accelerate reconstruction of SR 179, six roundabouts, and the Oak Creek Bridge while addressing the many environmental issues associated with the project and minimizing the inconveniences to the neighboring residents, businesses, and tourists. ADOT’s goals were to maintain one lane of free-flowing traffic in each direction of SR 179 throughout the construction zone, minimize traffic interruptions and queue lengths and, most important, improve safety, quality, and user satisfaction. The innovative features and accelerated construction elements of the ADOT HfL project included the following:
These innovative elements are described in the following subsections.
Innovative Public Outreach Campaigns
One of the key elements of the success of the SR 179 project was an unprecedented degree of public involvement at the community level. During the planning and construction phases of the project, ADOT proactively engaged in an outreach program that effectively kept the residents, businesses, and commuters along SR 179 corridor abreast of all construction activities.
Long before any heavy equipment or construction crews arrived on the jobsite, ADOT, through the NBIP process and the use of context-sensitive solutions, consulted with the residents and businesses on the design and reconstruction of SR 179 and obtained their input and feedback. For the most part, this process eliminated reworks, redesigns, and change orders. This effort allowed the community to choose alternate travel times to avoid peak traffic congestion because they were kept well informed of construction activities at all times.
An interactive Web site (www.scenic179.com) played a major role in keeping residents, businesses, and tourists informed of weekly activities. Figure 4 shows the Web site for the week of January 18, 2010, allowing viewers a glance at all the activities scheduled for the week and access to other information.
Figure 4. View of SR 179 Web site for the week of January 18, 2010.
In addition to the Web site, e-mails were sent weekly to residents and businesses to provide project updates and keep them abreast of upcoming project schedules and activities. An 800 number (hotline) was put in place to address community concerns. Once a month, a construction chat was held to allow the public to provide feedback and express likes and dislikes. ADOT’s resident engineer had a monthly interview with a local radio station (figure 5) to keep citizens of Sedona informed about the major construction activities affecting them. Figures 6 and 7 show camera crews interviewing a local policeman and a business owner about the impact of the project on the traveling public and businesses.
Figure 5. Resident engineer’s interview with Sedona radio station.
Figure 6. Sedona policeman on camera.
Figure 7. A local businessman on camera.
Innovative Sequencing and Staged Construction Techniques
ADOT took a corridor-based approach and bundled the construction of the six roundabouts, retaining walls, and Oak Creek Bridge and the installation of the Stormcepters into a seamless operation that minimized inconvenience to residents, tourists, and businesses and kept continuous traffic flow in each direction.
Innovative construction sequencing of the six roundabouts (building half of the roundabout at a time) and the carefully staged construction of the Oak Creek Bridge (the only access over Oak Creek) played a major role in the overall success of the SR 179 project. Figures 8 and 9 demonstrate construction of the biggest roundabout at SR 89A and SR 179.
Figure 8. Half-and-half construction of roundabouts.
Figure 9. SR 179 and SR 89A intersection before and after construction with fully functional two-lane roundabout.
Figure 10 shows the new divided SR 179 with the completed pedestrian walkway. The median and the space next to the pedestrian walkway were landscaped with native plants in spring 2010.
Figure 10. View of reconstructed SR 179 looking north.
Lane Rental Incentive/Disincentive Clauses
ADOT learned that incorporating performance-based incentive/disincentive clauses for lane rental could encourage the contractor to minimize road user impacts during construction. Under the lane rental concept, a provision for a rental fee assessment is included in the contract. The lane rental fee is based on an estimated cost of delay or inconvenience to the road user during the rental period.
The primary objective was to award the contractor as much as of the allotted lane rental funds as possible (i.e., incentive versus disincentive). The lane rental concept was a great success, even though the contractor was not awarded any incentive from the set-aside lane rental fee of $400,000. Because of the success of lane rental, the impact on the traveling public was significantly minimized. For the most part, as ADOT mandated, one lane in each direction of traffic remained opened for the duration of the construction.
Needs-Based Implementation Plan
Working through the NBIP process with ADOT and the community were agency stakeholders, including the Big Park Regional Coordinating Council, village of Oak Creek, Yavapai County, Coconino National Forest, Federal Highway Administration (FHWA), city of Sedona, and Coconino County.
ADOT followed an innovative approach to improving SR 179 known as a Needs-Based Implementation Plan process. The NBIP was the result of a collaborative process that evaluated existing corridor conditions and used community values and technical analysis of present and future user needs as the foundation for solutions. The process included a broad and continuous dialogue with the community and stakeholders, as well as indepth technical analysis of alternative improvement strategies. Throughout the process, ADOT solicited unprecedented input and involvement from the relevant jurisdictional agencies and community using a variety of methods to encourage participation, including interactive activities and events, educational forums, surveys, booths, newsletters, and a variety of media outreach. Public input opportunities were provided for people who had only enough time to check a Web site or complete a questionnaire as well as for those who could commit to intense participation in one of a series of three week-long charrettes. A major communications program was an integral part of the NBIP process, including innovative use of a comprehensive project Web site, an e-newsletter, and intense media outreach in addition to direct mail. Communication materials served a multitude of purposes, providing public education on basic transportation concepts and tradeoffs between alternative solutions, encouraging participation, and ensuring an informed community.
"We learned from our experiences. Solutions brought forward by previous efforts were not supported by the community," said Jennifer Livingston, then senior project manager for ADOT. "As a result we were at a stalemate. This is a positive step forward and now we are working together to incorporate community values into improvements for SR 179 through the village of Oak Creek to the 'Y' in Sedona." Beginning in August 2003, thousands of community comments were received and thousands participated in events and surveys, a very positive response and enthusiastic turnout.
In addition to community interviews, focus groups, educational forums, open exhibits, and workshops, a series of three multiday, collaborative charrettes was conducted to identify the complete range of planning concepts, fine tune the concepts, and select the preferred concept. Each charrette represented a major decision point for the project and provided specific direction for all subsequent work by the project team. The charrettes used a variety of techniques, including small group discussions, visual corridor characteristics surveys, comment cards, trolley talks, gaming, and prioritization exercises. One participant commented, "It is the first time in a long time in Sedona that we were able to stand shoulder-to-shoulder with people that have very different viewpoints regarding SR 179 and it didn’t end in a shouting match."
For 2 years, two teams guided the NBIP process. The main role of the Executive Team, which included two representatives from each agency stakeholder, was to monitor the process and provide decisions at key project milestones. A Public Outreach Team, which included one representative from each agency stakeholder, served as advisors for the public outreach program, working closely with ADOT and the consultants.
All communication materials (meeting handouts, questionnaires, postcards, newsletters, e-newsletters, PowerPoint presentations, maps, exhibits, graphics, etc.) were reviewed and approved by the Public Outreach Team (citizen- and agency stakeholder-based) and Project Management Team (ADOT and consulting teams) before public use.
Aerial photographs were used for a gaming workshop during Charrette #2, during which citizens placed a wide range of "game pieces" (sidewalks, lanes, medians, pullouts, signals, roundabouts, etc.) to show their preferences. Visual simulations showed how intersections would look with roundabouts versus signals, meandering paths, lanes with medians, and bifurcation, among other techniques. Video was played at Charrette #3 to show traffic simulations of project traffic flow through the Oak Creek and at the "Y" intersection in Sedona. Artist renderings displayed the potential character of the roadway, business access, landscaping, and pedestrian crossings, depending on the alternative.
Participants in every event were asked to complete an evaluation sheet to rate the event from 1 (lowest) to 5 (highest) based on meeting location, quality of presenters, information presented, interest in the topics, and how well the event was planned and organized. Evaluations were analyzed and comments summarized, and subsequent events were planned to continuously improve on the events and the public outreach approach. On the 30-some events held over 9 months, the team received an average score of 4.6 out of a possible 5.
A complete report from each event and survey was posted on the project Web site (www.scenic179.com) for the public to access and review. Twenty-seven event reports are available online for Charrette #1. Community comments were extremely complimentary, especially on the quality of the process, events, and materials.
The NBIP process consisted of three phases: the process definition phase, during which the project team and agency stakeholders agreed on the process flow and supporting public outreach process for the ensuing 18 months; the corridorwide framework phase; and the segment concept design phase. The corridorwide framework represented impressive community consensus on main transportation elements of the corridor, such as lane configurations, intersections types, and multimodal accommodations. The end of the segment concept design phase marked the completion of the NBIP, about a 30 percent design. Other NBIP implementation milestones included the following:
Before initiation of the NBIP process, community and agency trust of ADOT was at an all-time low. Trust has been restored between the government agencies and the community, as well as among the agencies. The potential consequences of not implementing a collaborative process were staggering. The process proved that open communication and committed leadership are keys to successful working relationships, which save time and money on projects.
Maintaining a comprehensive and ongoing public outreach program ensured that transportation planning initiatives were implemented in an equitable manner. Also, the Executive Team structure ensured that impacts on any one community or area would not be disproportionate with impacts elsewhere. One of the critical roles the Public Outreach Team served was to ensure that all community members were involved and, more important, that all viewpoints were recognized. After every public event, the Public Outreach Team discussed the participation and input received . It constantly reviewed and improved strategies for public outreach efforts to ensure maximum participation.
The Executive Team was involved at every step in the process, providing approval of the NBIP process, the vision and core values, the evaluation criteria and process, the preferred planning concept, and the final corridorwide design framework. At the completion of the NBIP in November 2004, it approved the segment concept design plans, the NBIP, and the access management and corridor management plans.
Public and stakeholder involvement was not an afterthought in the SR 179 project as it is in many public agency planning studies. The government agencies with jurisdictional responsibility along the corridor were involved from the genesis of the project. The scope of work for the corridor development and public outreach consultants was prepared in an intense collaborative effort with the agencies. In addition, representatives of the various agencies sat on the selection panels for both consultant contracts. The coordination of the multiple agencies was comprehensive and remained strong throughout the NBIP process.
Community involvement led the technical development of the NBIP, and the public had primary responsibility for the creation of the preferred planning concept. Instead of reacting to an alternative, the public created the alternative. To ensure that the public and stakeholders had the tools to develop a buildable plan, ADOT, agency stakeholders, and the consulting teams implemented a comprehensive education and public involvement program. Success of this involvement process required the ability to communicate complex technical terms and concepts in ways the general public would understand. Also, careful attention was given to creating events and techniques that would result in the appropriate type of input at the appropriate time in the process. Being committed to a comprehensive and open process and ensuring milestone decisions were made resulted in minimal backtracking on ideas, concepts, and solutions as the project evolved and new participants entered the process.
Project communications were regularly distributed to every household in the community (about 15,000) as well as to individuals outside the community who expressed interest via mail, the project Web site, and newspaper inserts. A comprehensive database of about 3,000 names evolved throughout the process as participants signed up.
The SR 179 NBIP process was coordinated with several local and regional transportation studies. The Uptown Sedona Enhancement Project, which included a traffic circulation study that directly connects to SR 179; the Sedona Transit Study; and the Yavapai County Regional Transportation Study were conducted simultaneously. The NBIP process was also coordinated with a gasline siting project in the corridor and the development of a Forest Service Information Center. The SR 179 NBIP process was also coordinated with access management and corridor management plans for the SR 179 corridor. The processes were woven together, but resulted in separate documents. Coordination of these studies maximized resources, staffing, and public involvement while not confusing the public about the various processes.
As a result of the successful collaborative effort, the NBIP process held up as a model for future local and regional planning processes by ADOT, the counties, FHWA, and the Forest Service. The NBIP public dialogue also renewed community discussions on innovative and sometimes controversial issues and fostered a belief that if consensus could be reached on a solution for SR 179, the area could tackle any community issue in a positive, collaborative manner.
Reverse Cantilever L-Wall Style Retaining Wall
Figure 11 shows a section view of a reverse cantilever L-wall style retaining wall.
Figure 11. Typical reverse L-wall style retaining wall.
A reverse cantilever L-wall style retaining wall was installed at select locations to minimize right-of-way impacts and excavation limits while providing a durable, functional, and aesthetically pleasing retaining wall (see figure 12). This type of wall design reduced right-of-way impacts and eliminated the total taking of multiple residences in the corridor.
Figure 12. L-walls minimized right-of-way impacts.
Implementation of a New Form of Project Management
One of the key success factors in the SR 179 project was the fact that ADOT kept the same project team for the duration of the project to work with the community during all phases of design, development, and construction. Typically, a project is handed off to different teams for planning, design, and construction. Having the same team for the duration of the project minimized questions that can arise during construction on the intent of the design and resulted in the project being constructed more efficiently and cost-effectively, lessening the impact on the neighboring community, businesses, and traveling public.
Implementation of Innovative Pilot Program to Train Local Law Enforcement
ADOT implemented an innovative pilot program to train local law enforcement personnel on enforcing laws in and around the project construction zone. The 1-day training class educated officers the on hazards of working in a construction zone, traffic calming techniques, public awareness, and ADOT’s expectations. In addition, ADOT hired additional law enforcement officers to provide a visible presence throughout the project. In fact, the typical number of officers was doubled, and they were positioned at strategic locations throughout the work zone, not just at the beginning, which is normally the case. This drew the attention of the traveling public, promoted slower speeds, and improved work zone safety for everyone.
Foamed Concrete (Lightweight Fill)
Foamed concrete was used to raise the vertical profile of the existing box culvert at Morgan Wash. The use of this innovative material was necessary to reduce the dead load on the existing culvert. The structural capacity of existing culvert was not adequate to support the weight of the additional concrete necessary to raise the roadway.
The foam concrete weighs 33 pounds per cubic foot (lb/ft³), much less than conventional concrete at about 150 lb/ft³. Figure 13 demonstrates the lightness of the foamed concrete.
By using foamed concrete, ADOT was able to eliminate the need for and expense and time-consuming effort normally associated with subexcavation, removal, and replacement of the existing culverts. In addition to saving money and time, ADOT was able to build a long-lasting infrastructure, substantially accelerate the construction, and reduce the impact on the traveling public.
Figure 13. Demonstrating the lightness of a 4x8-in foamed concrete cylinder.
Innovative Oil/Sediment Filtering Devices
Oak Creek is a waterway that runs alongside SR 179 in Sedona. Because Oak Creek is designated as a "unique waterway," ADOT took extraordinary measures to maintain the water quality during and after construction. During the construction of the new bridge and demolition of the old one, the creek was temporarily diverted and the quality of the water monitored at key locations. During construction, ADOT installed four innovative oil/sediment filtering devices as a pilot on this project. To the project team’s knowledge, these were the first oil/sediment filtering devices installed on an ADOT facility.
Sets of two oil/sediment filtering devices were installed at two different locations (figures 14 and 15) to filter the water from Oak Creek runoff and roadway runoff. The oil/sediment filtering device (trade name Stormcepter) is a precast concrete system designed to capture and remove a wide range of particle sizes as well as well as free oils and suspended solids from storm water.
Figure 14. Stormcepters before installation.
The system is a patented scour-prevention technology that ensures pollutants are captured and contained. Although this is a new application for ADOT, the Stormcepter equipment has undergone a vigorous field and laboratory investigation in the industry.
Figure 15. Stormcepters after installation at Morgan Wash.
Prefabricated Bridge Components
The entire pedestrian/utility bridge was prefabricated in Phoenix using a clear span weathering steel truss so that all utilities (wet and dry) can be relocated to it. The bridge was delivered to the jobsite and was secured at either end to abutments.
The abutments for the bridge were constructed before the prefabricated bridge was moved to its final position. These abutments were supported at one end by a drilled shaft and at the other end by a spread footing. Figure 16 shows the front of the west abutment wall, and figure 17 shows the new pedestrian bridge and the relocated utilities from the existing Oak Creek Bridge.
Figure 16. Front view of the pedestrian bridge abutment.
Figure 17. The utilities and the prefabricated pedestrian bridge.
Figure 18 shows the existing Oak Creek Bridge during construction. All utilities (wet and dry), including water, gas, electrical, cable, telephone, and sewer, were relocated to the new pedestrian bridge. This allowed the demolition of the existing vehicular bridge without any conflicts with utility relocation or lengthy impact on traffic flow.
Figure 18. Existing Oak Creek Bridge during construction.
Figures 19 and 20 show the plan and elevation view of the pedestrian bridge. As shown, the east abutment is supported by a spread footing and the west abutment is supported on a drilled shaft.
Figure 19. Plan view of the prefabricated pedestrian bridge.
Figure 20. Elevation profile of the prefabricated pedestrian bridge.
Other utility relocation options that were proposed and investigated included boring under Oak Creek, which would have been extremely expensive for the six affected utilities as well as environmentally disruptive. This was ADOT’s first attempt to build a joint pedestrian/utility bridge in Arizona. The new Oak Creek Bridge was realigned to a 135-degree curve to smooth out the 90-degree bend at the Schnebly Hill Road intersection. Figures 21 through 23 show the typical sections (spans 1 through 3) and plan view of the new Oak Creek Bridge.
Figure 21. New Oak Creek Bridge typical section (span 1.)
Figure 22. New Oak Creek Bridge typical sections (spans 2 and 3).
Figure 23. Plan view of the new roundabout and Oak Creek Bridge.
Construction of the first and second phases of the new Oak Creek Bridge is shown in figures 24 and 25.
Figure 24. Construction of the first phase of the new Oak Creek Bridge (prefabricated pedestrian bridge already constructed in the background).
Figure 25. Construction of the first phase of the new Oak Creek Bridge with the already-built pedestrian/utility bridge in the background.
The pedestrian experience was also enhanced with an underpass. Saving the native trees was one of ADOT’s main concerns. As figure 26 shows, during the construction of the pedestrian underpass, ADOT saved the trees by laying the sidewalk around them.
Figure 26. The pedestrian underpass and the saved trees.