active traffic management

CPHX

© All Rights Reserved, 2010

DRAFT TECHNICAL MEMORANDUM:ACTIVE TRAFFIC MANAGEMENT Note: This document presents a planning level assessment of the feasibility of various improvementstrategies for consideration when developing MAG’s NexGen RTP. The RTP process would include further technical evaluation and vetting of the strategies with stakeholders and the public.

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CENTRAL PHOENIX TRANSPORTATION FRAMEWORK STUDY

TECHNICAL MEMORANDUM Page i of i Integrated Corridor Management Strategies May, 2014

TableofContents

1.0 INTRODUCTION ............................................................................................................................................... 1

2.0 BACKGROUND ................................................................................................................................................. 2

3.0 ACTIVE TRANSPORTATION AND DEMAND MANAGEMENT ............................................................................... 3

3.1 ACTIVE TRAFFIC MANAGEMENT ..................................................................................................................................... 3 3.1.1. Speed Harmonization .................................................................................................................................... 3 3.1.2. Hard Shoulder Running.................................................................................................................................. 5 3.1.3. Junction Interchange Control ........................................................................................................................ 5 3.1.4. ATM Summary ............................................................................................................................................... 6

3.2 MANAGED LANES ....................................................................................................................................................... 8 3.2.1. The Concept ................................................................................................................................................... 8 3.2.2. Future Application ......................................................................................................................................... 9

4.0 OPERATIONS AND MAINTENANCE REQUIREMENTS ....................................................................................... 10

4.1 OPERATIONS STAFFING .............................................................................................................................................. 11 4.2 MAINTENANCE COSTS ................................................................................................................................................ 14

4.2.1. Speed Harmonization Maintenance Costs. .................................................................................................. 14 4.2.2. Life Cycle Maintenance Costs ...................................................................................................................... 15 4.2.3. Cost Increase Summary ............................................................................................................................... 15

5.0 NEXT STEPS ................................................................................................................................................... 16

6.0 CONCLUSION ................................................................................................................................................. 17

ListofFigures

FIGURE 1 FOUR INTEGRATED CORRIDOR MANAGEMENT AREAS ............................................................................................................ 1 FIGURE 2 VARIABLE SPEED LIMITS AND DYNAMIC LANE ASSIGNMENT SIGNAGE (I‐5 IN SEATTLE) ................................................................ 4 FIGURE 3 SIDE‐MOUNTED VARIABLE SPEED LIMIT SIGN ...................................................................................................................... 5 FIGURE 4 HARD SHOULDER RUNNING WITH VARIABLE SPEED LIMIT AND DYNAMIC LANE ASSIGNMENT ........................................................ 6 FIGURE 5 EXAMPLE OF STANDALONE HARD SHOULDER RUNNING: ........................................................................................................ 6 FIGURE 6 GRAPHIC DEPICTION OF JUNCTION INTERCHANGE CONTROL FOR AN ON‐RAMP .......................................................................... 7 FIGURE 7 EXAMPLE OF JUNCTION INTERCHANGE CONTROL: ARROYO SECO PARKWAY TO INTERSTATE 5, LOS ANGELES, CA ............................. 7 FIGURE 8 HIGH‐OCCUPANCY TOLL (HOT) LANE ENTRANCE SIGNAGE .................................................................................................... 9 FIGURE 9 WSDOT OPERATOR AT ATM CONTROL CONSOLE ............................................................................................................. 14 FIGURE 10 CLASSIC IEEE BATHTUB CURVE FOR ELECTRONIC DEVICES AND SYSTEMS ............................................................................... 15 FIGURE 11 EXAMPLE OF ACTIVE TRAFFIC MANAGEMENT SCREENING ................................................................................................... 18

ListofTables

TABLE 1 SUMMARY OF PROPOSED INTEGRATED CORRIDOR MANAGEMENT (ICM) STRATEGIES FOR CENTRAL PHOENIX ................................... 2 TABLE 2 BENEFITS OF ACTIVE TRAFFIC MANAGEMENT ........................................................................................................................ 8 TABLE 3 WSDOT TMC FUNCTIONAL ACTIVITY LOADING .................................................................................................................. 12 TABLE 4 WSDOT PEAK‐HOUR CONTROL ROOM STAFFING: ESTIMATES BY POSITION ............................................................................ 13 TABLE 5 APPROXIMATE CAPITAL AND O&M COSTS FOR CPHX ATM .................................................................................................. 16 TABLE 6 APPROXIMATE SUMMARY OF INTEGRATED CORRIDOR MANAGEMENT (ICM) IMPLEMENTATION PLAN ........................................... 17


TECHNICAL MEMORANDUM Page 1 of 18 Integrated Corridor Management Strategies May, 2014

1.0 Introduction The AZTech Strategy Task Force recently developed an “Integrated Corridor Management (ICM) Action Plan” to identify key operational improvements, intelligent transportation system (ITS) infrastructure needs, and priorities and responsibilities to advance ICM in the Phoenix region. The ICM Action Plan focuses on implementation of ICM strategies within four primary travel corridors serving the central portion of the Phoenix metropolitan area (Figure 1):

I-10 West – Interstate 10 West (Papago Freeway) between Loop 101 (Agua Fria Freeway) and Interstate 17;

I-17 – Interstate 17 (Black Canyon Freeway) between Loop 101 (Agua Fria-Pima Freeways) at the “North Stack” and Interstate 10 (Papago Freeway) at the “The Stack”;

Central Corridors –

o Interstate 10 (Papago Freeway) at “The Stack” to Priest Drive on the Loop 202-Red Mountain Freeway;

o Interstate 17 from “Durango Curve” to Interstate 10 (Papago/Maricopa Freeways) at “The Split” to “Broadway Curve” on Interstate 10 (Maricopa Freeway).

I-10 East and Loop 101 South –Interstate 10 East (Maricopa Freeway) between Broadway Curve and Loop 202 (Santan-South Mountain Freeway) at “Pecos Stack” and Loop 101 (Price Freeway) between US-60 and Loop 202 (Santan Mountain Freeway).

These five travel corridors highlighted by the Task Force incorporate the critical I-17/I-10 “Spine Corridor,” which consists of four segments:

Interstate 17 from the “North Stack” to Interstate 10 (Papago Freeway) at “The Stack;” I-17 from “The Stack” to Interstate 10 (Papago/Maricopa Freeways) at “The Split;” Interstate 10 (Papago/Maricopa Freeways) at “The Split” to Interstate 10 East (Maricopa Freeway) at

US-60 (Superstition Freeway); and Interstate 10 East (Maricopa Freeway) at US-60 (Superstition Freeway) to Loop 202 (Santan-South

Mountain Freeway) at the “Pecos Stack.”

These five corridors have parallel travel networks consisting of freeways and arterials with cross-connecting links that permit individual facilities to be readily accessible one to another. As such, the corridors offer significant opportunities for the deployment of ICM strategies. It is important to note that travel on connecting corridors, such as US-60 (Superstition Freeway) and Loop 202 (Santan Freeway) must be taken into account when forming ICM strategies in the five key travel corridors.

This Technical Memorandum builds on the high-level recommendations presented in the ICM Action Plan by (1) identifying additional freeway operational enhancements, such as Active Traffic Management (ATM), that might be included in the overall plan, and (2) presenting a potential methodology (Next Steps) for implementing the ICM system and related operational concepts and strategies.

FIGURE 1 FOUR INTEGRATED CORRIDOR MANAGEMENT AREAS

“The Spine Corridor”

Miles

0 3 6



2.0 Background The Federal surface transportation funding program MAP-21, Moving Ahead for Progress in the 21st Century (P.L. 112-141) addresses the concept of “Transportation System Management and Operations” (TSMO), defining TSMO as follows:

“Integrated strategies to optimize the performance of existing infrastructure through the implementation of multimodal and intermodal, cross-jurisdictional systems, services, and projects designed to preserve capacity and improve security, safety, and reliability of the transportation system.”

MAP-21 identifies numerous strategies and operational concepts that are included in TSMO. These strategies include: traffic detection and surveillance, corridor management, freeway management, arterial management, traveler information services, traffic control, commercial vehicle operations, and coordination of highway and transit operations. MAP-21 also identifies institutional coordination of regional TSMO investments, requiring agreements, integration, and interoperability to achieve targeted system performance, reliability, safety, and customer service levels. Nearly all of these strategies are identified in the AZTech Task Force ICM Action Plan (Table 1).

TABLE 1 SUMMARY OF PROPOSED INTEGRATED CORRIDOR MANAGEMENT (ICM) STRATEGIES FOR CENTRAL PHOENIX

ICM Approach ICM Strategies Specific Actions

Information Sharing Automated Information Sharing (data and video) – En‐route traveler information devices owned / operated by network agencies (e.g., DMS) used to describe current operational conditions on another network within the corridor Shared control of CCTV

Upgrade ADOT FMS infrastructure (DMS, CCTV, detection) Implement communication links to enable local TMCs to share camera images and data Upgrade regional systems (RCN, RADS, VDS) to enable video sharing with law enforcement, traffic management, and transit Implement additional traveler information capabilities to support area/corridor alerts. Expand Traffic.com data Active distribution of CAD alerts Provide travel time information/comparison (HOV versus General Purpose lanes)

Improve Operational Efficiency of Networks and Junctions

Multi‐network incident response teams/service patrols and training exercises Transit signal priority Coordinate operations between interchange and arterial signals

Incentive programs for towing/quick clearance Additional Freeway Service Patrols Enhance arterial traffic incident response times Traffic signal priority for buses, when incidents occur ADOT signal control of ramp interchanges during incidents

Accommodate/Promote Cross‐Network Diversions and Modal Shifts

Modify arterial signal timing to accommodate traffic shifting from freeway Modify ramp metering rates to accommodate traffic shifting from arterial Promote route shifts between roadways via en route traveler information devices

Deploy real‐time CCTV monitoring capability on arterials Develop traffic signal timing plans for diversions Links from Phoenix signal system to ADOT to allow control of signal system Establish traffic diversion/response plans for closure scenarios along I‐10 Post arterial alternatives on ADOT DMS Provide information on nearest Park and Ride facilities

Manage Capacity– Demand Relationship

None None

Notes: ADOT = Arizona Department of Transportation DMS = Dynamic Message Sign RADS = Regional Archived Data System CAD = Computer Aided Dispatch FMS = Freeway Management System RCN = Regional Community Network CCTV = Closed‐Circuit Television HOV = High‐Occupancy Vehicle VDS = Video Distribution System TMC = Traffic Management Center

Source: ICM Approaches and Strategies from Federal Highway Administration (FHWA) ICM Implementation Guidance.



There are several recurring themes in the ICM Action Plan relative to the five travel corridors:

Heavily traveled freeway segments have recurring congestion in the AM and PM peaks; Incidents that cause lane restrictions or closures significantly impact traffic throughput and safety and can

cause severe congestion on the larger freeway system and overwhelm adjacent arterials; and Heavy long-haul truck traffic occurs is prevalent within the corridor, particularly along “The Spine” and

Interstate 10 West corridors.

The focus of ICM in the Central Corridors is identified as “…enhancing freeway infrastructure and services to support traffic movement.” Accordingly, in addition to freeway enhancements identified in the ICM Action Plan, the concept of “Active Transportation and Demand Management” (ATDM) should be considered for inclusion in the overall ICM Action Plan. Inclusion of ATDM would add strategies that fall into the overall ICM approach of “Manage Capacity – Demand Relationship Within Corridor.”

3.0 Active Transportation and Demand Management ATDM is specifically identified in MAP-21 as one of the components of TSMO. ATDM is defined as the dynamic management, control, and influence of travel demand, traffic demand, and traffic flow of transportation facilities.1 Through the use of available tools and assets, traffic flow is managed and traveler behavior is influenced in real-time to achieve operational objectives, such as: preventing or delaying breakdown conditions; improving safety; promoting sustainable travel modes; reducing emissions; or maximizing system efficiency.

In the context of further promoting ICM, the most promising ATDM approaches for the central Phoenix area appear to be ATM and Managed Lanes.2 Each of these approaches is discussed below.

3.1 Active Traffic Management ATM offers an approach to congestion management that is more holistic and one that can include current applications of Managed Lane strategies to alleviate traffic flow issues associated with congested freeway corridors. ATM is defined as:

…the ability to dynamically manage recurrent and non-recurrent congestion on the mainline based on prevailing traffic conditions. Focusing on trip reliability, ATM maximizes the effectiveness and efficiency of the facility. It increases throughput and safety through the use of integrated systems with new technology, including the automation of dynamic deployment to optimize performance quickly and without delay that occurs when operators must deploy operational strategies manually.3

3.1.1. Speed Harmonization

One set of ATM strategies focuses on speed harmonization. This strategy is employed to stabilize the speed distribution of traffic flows such that differences between the highest and lowest vehicle speeds are minimized. Speed harmonization results in more uniform traffic flow, thereby promoting safety and reducing incidents that interrupt (e.g., aggressive weaving) or disrupt (e.g., crashes) traffic flow. Speed harmonization also can help reduce flow breakdown and the onset of stop-and-go driving in support of improved mobility. An example of three components of the speed harmonization strategy at work is shown in Figure 2 and described below:

Variable speed displays are set (and varied) according to predominant roadway and operating conditions. These conditions may include: real-time traffic flows/congestion levels, visibility, weather, lane constraints (e.g., work zones), crashes, and other factors. Variable speed displays may be advisory or regulatory. Regulatory variable speed limits are legal speed limits for which motorists can receive citations, if they exceed the posted limit.4

1 Transportation Research Circular E-C166. “Glossary of Regional Transportation Systems Management and Operations Terms.” August 2012. 2 Additional discussion of this subject may be reference in Synthesis of Active Traffic Management Experiences in Europe and the United States” published by the

Federal Highway Administration (FHWA), Publication # FHWA-HOP-10-031, dated March 2010. 3 Ibid. 4 Per the 2012 Arizona Revised Statutes (ARS), Title 28, Transportation, 28-702 State highway speed limits: “The director may establish varying speed limits for different

times of day, different types of vehicles, varying weather conditions and other factors bearing on safe speeds. The varying limits are effective when posted on appropriate fixed or variable signs.” Variable speed limits are also part of the Arizona Statewide ITS Architecture.



FIGURE 2 VARIABLE SPEED LIMITS AND DYNAMIC LANE ASSIGNMENT SIGNAGE (I‐5 IN SEATTLE)



Dynamic lane assignment consists of lane control signals typically installed in conjunction with variable speed displays. Dynamic lane assignment provides advance notice of the closure of a lane or lanes ahead, advising vehicle operators to begin the merge process into the available lanes well in advance of the actual closure.

Queue warning involves the use of signs (in some instances, flashing lights) to alert motorists about downstream queues. Queue warnings can be used in conjunction with variable speed displays to slow traffic and with lane control signals to direct traffic to alternate lanes, if the queuing is caused by a blocked lane.

Speed harmonization is relatively new in the United States. Operational systems currently are in place in Seattle, WA, and Minneapolis, MN, as part of the Federal Highway Administration (FHWA) Urban Partnership Agreement. A similar system is being installed in northern Virginia. The State of Delaware and New Jersey Turnpike Authority use variable speed limits without the dynamic lane assignment. Variable speed limit signs often are mounted on the side of the roadway (Figure 3).

3.1.2. Hard Shoulder Running

Another ATM strategy is hard shoulder running (HSR), or temporary shoulder use. This strategy involves temporary use of the outside or inside paved shoulder as a travel lane. Often, HSR is limited to morning or evening peak periods, when recurrent congestion most often occurs. HSR temporarily increases available facility capacity and decreases congestion. In other instances, HSR may improve traffic flow in the general purpose (GP) lanes during incidents and special events. HSR is implemented in conjunction with variable speed displays and dynamic lane assignment and control systems, as shown in Figure 4; although, it can operate alone, as is done in Boston and northern Virginia (Figure 5). This also is a practice employed in some larger metropolitan areas specifically to expedite the movement of transit vehicles through heavily congested corridors.

HSR applications imply the additional road space may be used to carry normal traffic or transit traffic rather than acting as emergency reserve capacity or place of refuge. Nevertheless, HSR appears to have potential application along many segments of the five travel corridors identified within the CPHX study area. As noted in the ICM Action Plan, the Interstate 10 West corridor has wide outside shoulders and a wide median. A preliminary field review indicates some of the other corridors may have similar conditions providing opportunities for implementing this type of ATM strategy. Additional investigations will be necessary to confirm existing shoulders have adequate width and structural depth to accommodate various traffic loads and run continuously across a stretch of several interchanges. Ramp treatments and coordination with incident management operations also are important considerations associated with implementing this ATM strategy.

3.1.3. Junction Interchange Control

Even if the existing shoulders generally are not suitable for hard shoulder running for long continuous stretches of roadway, the shoulders may still be used as short sections of roadway approaching an interchange. Junction interchange control is a strategy employed to dynamically change lane allocations at interchanges, based on mainline and entering and exiting ramp volumes. Junction interchange control is useful for situations where a varying relationship between mainline demand and ramp demand occurs. This strategy allows a ramp to be allocated one

FIGURE 3 SIDE‐MOUNTED VARIABLE SPEED LIMIT SIGN



or two lanes, depending on demand on the ramp and the mainline volume. Through the use of lane

control signs (and sometimes lighted pavement markings), junction interchange control can be used to close a mainline lane and create a second lane on the ramp for entering or exiting traffic, whenever there is significant ramp demand. Figure 6 displays how this is implemented for an on-ramp. Junction interchange control also can be used for off-ramps, when exiting traffic requires more than the normal designated exit lane(s) during peak periods or special events (Figure 7).

3.1.4. ATM Summary

FIGURE 4 HARD SHOULDER RUNNING WITH VARIABLE SPEED LIMIT AND DYNAMIC LANE ASSIGNMENT

Source: Figure 28. Photo. Right Shoulder Use with Speed Harmonization—Germany, from Chapter 4, Case Studies, Efficient Use of Highway Capacity Summary Report to Congress, Federal Highway Administration (FHWA) Office of Operations at http://www.ops.fhwa.dot.gov/publications/fhwahop10023/chap4.htm.

FIGURE 5 EXAMPLE OF STANDALONE HARD SHOULDER RUNNING:

INTERSTATE 66, VIRGINIA



ATM has been widely used in Europe (United Kingdom, the Netherlands, and Germany) with significant safety and mobility benefits, as summarized in Table 2. Deployment of ATM strategies along selected corridor segments would expand the palette of ICM concepts to include management of the demand/capacity relationship.5 Moreover, by reducing the occurrence of traffic flow breakdowns and number of crashes, the need for and instances requiring diversion of traffic to other freeways and adjacent arterials (facilities that may not have the available capacity to accommodate this additional traffic) may be reduced.

5 Variable speed limits is one of the strategies identified in the Federal Highway Administration ICM Implementation Guidance for this approach.

FIGURE 7 EXAMPLE OF JUNCTION INTERCHANGE CONTROL: ARROYO SECO PARKWAY TO INTERSTATE 5, LOS ANGELES, CA

Dynamic Lane Assignment indicates two left lanes for I‐5 Northbound OK on Northbound Arroyo Seco Parkway/Pasadena Freeway at Solano Avenue

Northbound Arroyo Seco Parkway/Pasadena Freeway lanes available for Northbound Interstate 5 traffic

Image Source: Google Earth

FIGURE 6 GRAPHIC DEPICTION OF JUNCTION INTERCHANGE

CONTROL FOR AN ON‐RAMP



TABLE 2 BENEFITS OF ACTIVE TRAFFIC MANAGEMENT

(INCLUDING INTEGRATION WITH HARD SHOULDER RUNNING AND JUNCTION INTERCHANGE CONTROL)

Benefit Source

Increase of 3 to 7 percent in average throughput for congested periods Increase of 3 to 22 percent in overall capacity Decrease of 3 to 30 percent in primary incidents Decrease of 40 to 50 percent in secondary incidents

Federal Highway Administration (FHWA) 2006 international scan of ATM systems in Europe

Decrease in the average number of shockwaves per morning rush hour (from seven to five) Injury accidents decreased by 10 percent Damage‐only accidents decreased by 30 percent Emissions decreased overall by between 2 percent and 8 percent Weekday traffic noise adjacent to the scheme reduced by 0.7 decibels

Evaluation of the Managed Motorway System on the M25, London Orbital motorway (or Outer Ring Road) in the United Kingdom (UK), which incorporates variable speed limits and dynamic lane assignment

Travel times (PM) decreased by 24 percent Travel reliability increased by 27 percent Property damage‐only crashes reduced by 30 percent Benefit/cost ratio: 3.9

Evaluation of M42 in the United Kingdom

Decrease of 10 to 20 percent in fuel consumption and greenhouse gas emissions as a result of dynamic speed displays

Center for Environmental Research and Technology (CERT), University of California, Riverside

3.2 Managed Lanes

3.2.1. The Concept

Continuing population growth in the MAG region is anticipated to place ever increasing demands on the transportation infrastructure, particularly the freeway system. In light of the phenomenon of growth, increasingly difficult funding scenarios, complex right-of-way constraints in developed travel corridors, and potential neighborhood and environmental impacts, the realization is growing that construction of sufficient freeway lane capacity to provide free-flow conditions during peak travel periods cannot be accomplished. Therefore, innovative methods to improve the efficiency of existing and planned capacity through better management of traffic flows must be evaluated.

The concept of “Managed Lanes” is considered a viable method for meeting mobility needs. Communities are implementing Managed Lanes to aid in maintaining free-flow travel speeds on GP lanes of major facilities. The basic concept relies on providing to eligible groups of vehicles controlled service, which can vary by time of day or other factors, depending on available capacity and the mobility needs of the community. The concept of Managed Lanes is defined as:

Highway facilities or a set of lanes where operational strategies are proactively implemented and actively managed to optimize traffic flow and vehicular throughput. Managed lanes are freeway lanes that are set aside and operated using a variety of fixed or real-time strategies to move traffic more efficiently in those lanes. As a result, travelers have options to traveling on a congested freeway. 6

Interstate 10 and Interstate 17 currently have high-occupancy vehicle (HOV) lanes, and opportunities for adding direct HOV (DHOV) ramps at strategic locations recently were studied. In the broader context of ICM and Managed Lanes, HOV lanes could be converted to high-occupancy toll (HOT) lanes. The conversion would allow traffic engineers to regulate the use of the HOV lanes by permitting persons willing to pay a fee to have access.

6 Transportation Research Circular E-C166. “Glossary of Regional Transportation Systems Management and Operations Terms,” August 2012.



This access-for-fee usage is in addition to the standard use of the HOV lanes by 2+ person vehicles, transit, certain energy efficient vehicles, and motorcycles.

HOT lanes take advantage of available unused capacity in an HOV lane by allowing vehicles that do not meet the minimum occupancy requirement or other qualifying criteria to pay a fee or a toll for access to the lane(s). In the purest form, access to HOV/HOT lanes is managed through dynamic pricing geared to maintaining a high level of service during peak periods (for example, an average speed of at least 45 miles per hour in the HOT lanes 90 percent of the time). This operating standard is set to assure no degradation of service for the standard HOV lane users.

When traffic flow in the HOV/HOT lanes becomes heavy (as measured by detection and surveillance technologies), tolls automatically increase to discourage non-HOVs from entering. When traffic in HOV/HOT lanes is light, tolls decrease to encourage non-qualifying vehicles to enter for a fee to take advantage of unused capacity, thereby providing a consistent level of service in the HOV/HOT lane facility. Entry fee or toll information is conveyed to motorists through variable message signs located prior to entry points to the HOV/HOT lanes and other points along the roadway, as shown on Figure 8.

The photo on the right side of Figure 8 shows a combination of ATM plus HOT lanes (from Minneapolis). In the context of ICM, the HOT lane could be considered as a separate facility within the corridor, with tolls varied to promote (or discourage) diversions between the HOT lanes and the freeway lanes to achieve the optimum balance of traffic flow in accordance with FHWA guidelines for HOT lane conversions.

3.2.2. Future Application

In December, 2002, MAG commissioned the High Occupancy Lanes and Value Lanes Study to take a sort of first look at the potential for adapting HOV lanes to the HOT lane concept, which would involve attaching a fee to the use of HOV lanes by non-qualifying vehicles. One key result of this study was the following conclusion:

FIGURE 8 HIGH‐OCCUPANCY TOLL (HOT) LANE ENTRANCE SIGNAGE

SR 237 ‐ Calaveras Road Express Lanes, Santa Clara, CA

Combination of Active Traffic Management (Dynamic Lane

Assignment) and MnPASS HOT Lanes, on I‐35W approaching I‐494,

Minneapolis, MN



The State of Arizona would need to establish specific enabling legislation to allow tolls on new or existing state or interstate roadways, as well as to enable an entity to perform toll collection (operate) on the new toll facility or HOT lanes (see existing State of Arizona privatization statues). This enabling legislation should consider the bonding against toll revenue by the owner of the toll facility or HOT lanes, prescribe standards for electronic toll collection and permit enforcement of toll collection requirements.7

In addition, the study found that several other actions would be necessary before Managed Lanes (or Value Lanes) may be implemented as part of the regional transportation system:

1. Establish enabling legislation to permit the formation of toll authorities and respective powers; 2. Establish enabling legislation to define vehicle code statutes as part of operating and maintaining toll

facilities; 3. Establish technical standards for electronic toll collection (ETC); 4. Establish enabling legislation for toll violation enforcement and evasion collection procedures; 5. Re-evaluate and modify State Law relating to tax refunds or credits for anyone who pays motor vehicle fuel

license taxes, use fuel taxes or motor carrier fees while operating a motor vehicle on a roadway project.

Additional studies have been conducted regarding development of Managed Lanes with interest increasing as a result of the recent economic downturn that severely impacted the Federal, State, and regional transportation revenue base. The most recent White Paper addressing this matter concludes there is potential for implementing a managed lanes program in the MAG region in conjunction with the private partner, based on changes in the Federal highway program.8 It further states:

However, converting existing HOV lanes to HOT lanes pursuant to one of the various Federal programs without the participation of a private partner would require a legislative action granting ADOT or some other public entity the authority to toll the existing freeway system. It would also require further consideration of existing state laws and regulations that govern the use of HOV lanes.9

4.0 Operations and Maintenance Requirements

ATM, ICM, and the HOT lanes concepts require monitoring, direction, and maintenance by human operations personnel to achieve the desired operational benefits. Unfortunately, there is no standard formula for determining the number of operations personnel associated with a system. Section 4.1 presents factors known to be most relevant in anticipating impacts on operations staff from these advanced traffic management strategies. Maintenance requirements are more predictable, as the elements used in accomplishing these strategies have known maintenance characteristics and proven life expectancies as well as mean time between failure (MTBF) histories. Section 4.2 provides a discussion and estimate of maintenance requirements.

As part of the national ITS strategic planning program initiated by FHWA in 2005 to support policy “Rule 940,” an O&M cost estimation rule of thumb of 10% of capital cost was used to predict the first year O&M expense associated with ITS deployment. Experience again and again has lent credibility to this rule of thumb. Basically, a $10 million ITS installation will cost around $1 million to operate and maintain in the system’s first year of operation, including higher than typical rate of failure during the burn-in period. In practicality, maintenance cost will then decrease incrementally with time prior to the equipment reaching useful life. Operating costs also will increase incrementally, due to seniority and salary adjustments. Therefore, the overall operational cost of and ITS deployment should be relatively stable for the first ten years of operation.

7 High Occupancy Lanes and Value Lanes Study, Final Report, Arizona Department of Transportation (ADOT) and Maricopa Association of Governments (MAG),

December 2002, p. 11-7. 8 “Managed Lanes Legal and Regulatory Issues,” Managed Lanes Network Development Strategy – Phase I, Maricopa Association of Governments (MAG),

Revision 2.0, February 3, 2012, p. 16. 9 Ibid.



4.1 Operations Staffing Staffing levels of Traffic Management Centers (TMCs) varies across the United States. The level of staff required for operations depend primarily on three factors.

Functionality. The number of functions that place task loading upon operations personnel (operators). Typical functions are incident management, traveler information, ramp metering, traffic signal control, video monitoring, and flow monitoring.

Degree of Automation. This factor is simply the sophistication of the software providing the functionality. First-hand experience operating a fully integrated freeway and arterial corridor management system on Long Island for New York State Department of Transportation (NYSDOT) provides a glimpse of the complexity of this factor. The system covered 135 miles of highways with more than 3,000 detectors. It was designed to operate with no more than two human operators in peak hours and one in off-peak hours. The software (present day value of $15 million) provided such a high degree of automation that operators literally were there to handle exceptions, such as major incidents, or approve complex traffic diversion strategies based upon plans recommended by the system. All ramp meters, traffic signals, and even dynamic message sign (DMS) messages were fully automated.

Extent of Instrumentation. An advanced traffic management system (TMS) one mile long will require one operator, but a ten-mile system does not require ten operators. The freeway system in the central Phoenix study area is complex. When ADOT started the regional freeway management center (FMC), the Department employed several operators on duty in peak hours just to handle Phoenix. Later the center became a statewide facility (a national trend in the 1990’s). Although the operations staff increased slightly, in general, the existing staff was simply asked to cover more territory.

It is useful to consider the Washington State Department of Transportation (WSDOT) Traffic Management Center (TMC) in Seattle as a baseline in terms of operations for ATM. This TMC probably is the most fully functional ATDM operation developed to date in the United States with advanced features like speed harmonization. A study was conducted by CH2M HILL in 2012 to evaluate operator staffing levels and associated space requirements in support of the TMC mission to determine the requirements for constructing a new TMC.

Table 3 is reproduced here from the CH2M HILL report prepared for WSDOT. It presents the agency function, and an estimate of activity levels based on past WSDOT traffic operations experience with event loading over extended time periods. Each activity was assessed for its contribution to the overall annual workload accomplished by the TMC. The functions were rated relative to how critical each was to TMC mission. The rating was based on whether operator actions can effect life safety, provide a regulatory control enforceable by law, or provide information to motorists in an advisory capacity. CH2M HILL provided the quantities used in the column labeled “Operator Time/Event (minutes),” which were based on staff experience as an FMC supervisor and findings reported in the FHWA publication Guidelines for TMC Transportation Management Operations Technician Staff Development, FHWA-OP-03-071. The Full Time Equivalent (FTE) staffing level was based on a 40-hour-per-week, 50-week –per-year resource allocation. Determination of staffing levels required for this functional activity assumed the equivalent of a total staff complement of 25 persons operating the TMC 24 hours per day, seven days a week, 365 days per year (24 x 7 x 365), a modest increase over the 21.5 persons predicted prior to the study by WSDOT staff.

The WSDOT study used staff position descriptions and projected staff allocations (number of people) that were based on actual observation of complement of staff in the control room during the typical weekday peak-hour, as well as the staff working outside the control room (not assigned to a control room workstation) on a typical weekday. Table 4 highlights in the leftmost column the position descriptions used by WSDOT with the existing staffing applied to those positions in the column labeled “Existing.” The rows “Flow-Peak” and “Flow-ATM” are positions associated with operation of the ATM/ICM program. These two rows show the increase in staffing allocation attributable to implementation of an ATM strategy, essentially 1.5 additional persons (60 hours per week).



TABLE 3 WSDOT TMC FUNCTIONAL ACTIVITY LOADING

Agency Function

L (Life Safety)

R (Regulatory)

A (Advisory)

Events

Metric

(Period of Measurement)

Operator Time/Event (minutes)

Mileage/ Subsystem

Units Annual Load

(Hrs) FTE Employees

Peak freeway operations R/A 3.21 Per peak period 15 240 Miles 1670 0.83

Incident Management A 2 Per peak period 15 180 Miles 1040 0.52

Web Page Update (ATIS) A 2 Per peak period 5 1 Sites 347 0.17

Dynamic Message Sign A 0.25 Per peak period 1 380 Signs 3293 1.65

Traffic Busters (Video & Data Sharing) R/A 1 Per peak period 30 10 Partners 300 0.15

Interagency Coordination A 1 Per shift 30 10 Partners 300 0.15

Reversible Roadway Operations R 2 Per shift 30 20 Miles 1200 0.60

Active Traffic Management R 1 Per Shift 30 35 Miles 1050 0.53

Hard Shoulder Running R 1 Per shift 30 50 Miles 1500 0.75

Ramp Metering R 233 Per shift 2 233 Sites 1942 0.97

HOT Lanes/Tolling/Dynamic Pricing R 1 Per Shift 30 65 Miles 125 0.06

IRT‐FSP A 80000 Per Year 5 240 Events 6667 3.33

Logging A 220000 Per Year 0.5 240 Actions 1833 0.92

Maintenance Dispatching A 4,446 Per Year 30 160 Trucks 2223 1.11

City Coordination Alaska Viaduct Recon. A 720 Per Year 90 15 Future 1080 0.54

Alarm Monitoring (incl. floating Bridge) L 365 Per Year 120 4 Sites 2920 1.46

Emergency Contact (WSDOT & Interagency) A 104 Per Year 30 10 Partners 520 0.26

Traffic Signal Control R 1 Per shift 30 252 Intersections 7560 3.78

Traffic Busters (Video & Data Sharing) R 5 Per Week 90 10 Partners 3900 1.95

Tunnel Management L 2 Per Week 90 3 Sites 468 0.23

Media/Social Media A 720 Per Year 30 1 Sites 360 0.18

Web Page Update (ATIS) A 1 Per Year 30 1 Sites 1040 0.50

Media Press Meeting A 10 Per Year 90 1 Meetings 31200 1.50

Major events not requiring EOC activation A 6 Per Year 240 1 Activate 49920 2.50

FTE 25

Abbreviations: ATIS = Automatic Terminal Information Service HOT = High‐Occupancy Toll IRT = Incident Response Team FSP = Freeway Service Patrol WSDOT = Washington State Department of Transportation EOC = Emergency Operations Center FTE = Full Time Equivalent



Another important characteristic of the WSDOT operation in the Seattle metropolitan area is WSDOT created its own software with in-house employees. During observation of the operation, it was noticed that software engineers are often in the FMC participating in live operation. This goes back to the factor of “degree of automation.” The effective loading of the staff to operate the ATM may be higher to a minor degree, perhaps as many as three FTEs, to provide an effective operation of ATM in Seattle.

Figure 9 is a photograph taken by Dan Baxter of CH2M HILL, while observing the Seattle TMC operation in April of 2012. The photo shows a “Flow” Operator working monitoring the ATM system during a morning weekday peak period. The monitor on his left has an overall map of the Puget Sound freeway system and active ITS devices. The monitor in front of him displays the current functioning of the Speed Harmonization and “Trouping” Algorithms. The Trouping algorithm decides what devices to group together to address traffic slow-downs. The monitor on his right shows the current status of the ATM devices on I-5 in downtown Seattle. During the peak period, the ATM was monitored full time by this operator.

Translated to the Phoenix environment, which already has a fully functional freeway management Center operated by Arizona DOT, a conservative estimate for ICM and ATM increase on staffing requirements is three full time equivalent operators for peak periods, one for off-peak. This translates into an effective staff complement of nine to 12 persons annually, if operated 24 hours per day, seven days a week, 365 days per year with no person working more than 40 hours and a shift overlap of a one half-hour for transition. Based on an average hourly wage of $23 per hour with a 140% multiplier for benefits, an estimated annual salary of approximately $67,000 per person might be appropriate. The key differentiator would be the addition of two people to ADOT to staff this function at an increased cost $134,000 annually, or utilize a whole new staff at a new center at a cost of $670,000 annually.

TABLE 4 WSDOT PEAK‐HOUR CONTROL ROOM STAFFING: ESTIMATES BY POSITION

Control Room Function Existing

Traffic Management Center (TMC) Supervisor 1

Tunnel Management 0.5

Radio Dispatch 3

Flow‐Peak 1

Flow‐Active Traffic Management (ATM) 0.5

Ramp Metering 1

FLOW (HOT lanes, Tolling)* 1

Signal Operations 1

Public Information Officer (PIO) 1

Visitor Station 1

Security 0.0

TOTAL 11

*Note: FLOW is the WSDOT FLOW Evaluation Framework Design software (TRACFLOW) literally used to monitor traffic flow on roadways and HOV, HOT, and Managed Lanes.



4.2 Maintenance Costs Maintenance of the ATM system once installed will impact the current costs of maintenance staffing and equipment repair of an operating agency. Should the agency currently be operating a freeway management and/or traffic signal system, there will be baseline cost accounting information available, and the cost of ATM maintenance can be predicted as a marginal increase to the baseline.

4.2.1. Speed Harmonization Maintenance Costs.

If the ATM system includes Speed Harmonization capability and if posted speeds are regulatory in nature (i.e., enforceable by police), most agencies remove the standard fixed roadside speed limit signs so they do not conflict with speeds posted by software on DMS. The net result is that, if the DMS fails, it is possible that a ticket given to a speeding motorist might not be enforceable, if the maximum posting interval (1/2 mile in most states) was not met. Given this potential enforcement issue, the maintenance response time of the DMS system becomes critical to maintain the regulatory posting of enforceable speed limits. Keeping the DMS operational 24 hours per day, seven days per week, 365 days per year also uses more power, and shortens sign life. Therefore, it is advisable to operate the informational DMS system only when traffic conditions are less than optimal.

FIGURE 9 WSDOT OPERATOR AT ATM CONTROL CONSOLE

CH2M HILL Photo (Baxter)

MAP OF FREEWAY SYSTEM

CURRENT FUNCTIONING OF SPEED HARMONIZATION

AND “TROUPING” ALGORITHMS

CURRENT Status of ATM devices on I‐5

in Downtown Seattle

REAL TIME VIEW OF I‐5 FROM MONITORING

CAMERA



4.2.2. Life Cycle Maintenance Costs

Most agencies that install and maintain electronic equipment for outdoor applications are well aware of the classic “Bathtub Curve” formulated by the Institute of Electrical and Electronics Engineers (IEEE). The classic Bathtub Curve, depicted in Figure 10, conveys an expectation that a higher percentage of electronics will fail during a burn-in period than will fail during the expected operational life; and, eventually the failure rate will increase again as devices exceed their mean time between failure (MTBF) useful life expectancy. Although modern electronics tested prior to installation in the roadway environment experience mortality at a rate much lower than Figure 10 would suggest, it still is an issue. Most operating agencies simply cover this cost by requiring the installation contractor to provide maintenance during the burn-in period, typically ninety days.

In a quality assurance audit of the Seattle I-5 ATM installation, CH2M HILL measured the equipment mortality at 3.4 percent, meaning that 10 of the 317 new DMSs failed during the burn-in period. During the first year of operations, only four DMSs failed, lending credibility to the bathtub curve principle. A reasonable estimate for maintenance expense for study area freeways, based on this prior experience, would be a post-burn-in annual baseline increment of $50,000, plus $10,000 for each five center-line miles in addition to the first 10 center-line miles instrumented. This estimate is the incremental increase above the baseline, assuming that maintenance of ITS and the FMS already is in place on the same freeways.

4.2.3. Cost Increase Summary

For an initial implementation of thirty center-line miles of ATM instrumentation on an open freeway in downtown Phoenix, or with Managed Lanes, the costs shown Table 5 might be anticipated.

FIGURE 10 CLASSIC IEEE BATHTUB CURVE FOR ELECTRONIC DEVICES AND SYSTEMS

Source: The hzf (hazard function) over time (the classic bathtub curve). A Critical Look at the Bathtub Curve:Georgia‐Ann Klutke, Peter C. Kiessler, and M. A. Wortman IEEE TRANSACTIONS ON RELIABILITY, VOL. 52, NO. 1, MARCH 2003.

Equipment



TABLE 5

APPROXIMATE CAPITAL AND O&M COSTS FOR CPHX ATM

Option Miles Gantries

(Units)

DMS

(Units)

Hardware

(Mil$)

Software

(Mil$)

Capital Cost

(Mil$)

Annual Operations

Cost

(Mil$)

Annual Maintenance

Cost

(Mil$)

ATM with Speed Harmonization added to O&M costs of the Highly Automated, Freeway Management System, operated by ADOT

30 60 210 32.100 7.500 39.600 0.134 0.090

ATM with Speed Harmonization added to O&M costs of the Highly Automated, Freeway Management System, operated by a New Agency

30 60 210 44.940 8.500 53.440 0.670 0.290

ATM with Speed Harmonization added to O&M costs of a Freeway Management System with Low Automation operated by ADOT

30 60 210 32.100 1.500 33.600 0.201 0.090

Prepared by CH@M HILL.

5.0 Next Steps The inclusion of ATM strategies and/or Managed Lanes (i.e., HOT lanes) in the broader context of ICM operations would appear to provide added value to the region’s freeway system. At the same time, the cost of installing ATM and Managed Lane technology, which is has an estimated cost range of $1.12 million to 1.78 million per center-line mile (i.e., full roadway cross-section) for full implementation, could significantly add to freeway system costs. Moreover, inclusion of ATM and Managed Lanes may not be appropriate for all corridors. Feasibility, priority, and actual costs in each corridor would depend on several factors, including: level of congestion, crash history, and geometrics of the freeway segments.

The AZTech Task Force ICM Action Plan includes a high-level implementation plan (summarized in Table 6) that appears to be based on the principles of systems engineering and the ICM Implementation Guidance developed by FHWA. It is recommended that, prior to developing the Concept of Operations, an initial screening analysis should be performed to determine the feasibility of including ATM and/or Managed Lane concepts in identified ICM corridors. Assuming data for congestion, crashes, and ramp and HOV volumes are readily available, this screening analysis should take approximately one month to perform. The analysis will include the following activities:

Step 1 - WHAT? High-level qualitative assessment. This activity will determine at a high level whether ATM and/or Managed Lanes would reasonably add to corridor capacity. Safety data and congestion would be analyzed to identify whether there are safety or congestion issues that could be addressed using ATM or managed lanes strategies. Travel demand associated with the existing HOV lanes also would be examined to gain an understanding of potential impacts on current qualified users.

Step 2 - WHERE AND WHEN? Identify the scale and nature of the issues. This activity would involve analyzing specific congestion locations and times.



Step 3 - HOW MUCH? Quantitative assessment index. This activity would involve performing a comparative analysis of areas to determine safety and congestion scores.

Step 4 - HOW? Formation of program of measures based on relative assessments. This activity would involve grouping segments into a prioritized program and assessing the types of measures proposed for each section.

Figure 11 is an example showing the results of such an analysis for selected freeways in the Philadelphia area. The levels of the curves relative to the dashed lines indicate the priority for various roadway segments identified. Segments selected for ATM and associated strategies once identified in this manner can be incorporated into the ICM Concept of Operations and subsequent activities of an Implementation Plan, including pilot projects.

6.0 Conclusion ADOT has been operating an FMS since the 1980s. The City of Phoenix has been operating traffic signal systems since the 1940s. This report does not describe or address those systems. This report describes technologies and strategies to improve traffic flow and increase the capacity of the transportation infrastructure. These technologies and strategies are widely operational in many European countries, where fuel is much more expensive and environmental sustainability has stepped ahead of traveler convenience as the top social priority for motorway management. Closer to home, select cities in the United States have implemented these strategies, particularly large urbanized areas, where traffic congestion is severe and adversely affecting the quality of life of citizens.

According to a 2012 report published by the Texas Transportation Institute (TTI) relying on 2011 data, identifies Phoenix as having the distinction of being one of the top 15 worst traffic and travel cities in the United States. This is a distinction thought to be the harbinger of rising air pollution, decreased quality of life, and increased cost of living as well as falling property values. Rapid population growth, an expanded freeway system, and the accompanying increase in travel demand certainly are an integral part of these potentially deteriorating conditions. However, the gap between infrastructure needs and available, even future, funding to meet those needs severely constrains the ability of communities to keep pace with increasing travel demand.

The ATM, ICM, and ITS strategies documented and discussed in this report represent the next logical step to combat worsening travel conditions. They offer the potential to counterbalance the negative impacts of overuse of the transportation infrastructure with proven traffic management initiatives. It is clear from the cost estimates presented in Section 4 that the $1.12 million to 1.78 million per center-line mile required to implement (i.e., install and maintain) the entire toolbox traffic management strategies is within reach of most communities. Compared to

TABLE 6 APPROXIMATE SUMMARY OF INTEGRATED CORRIDOR MANAGEMENT (ICM) IMPLEMENTATION PLAN

Formal Concept of Operations for the four corridor areas to identify:

Specific operational needs and priorities

Roles and responsibilities (and change from current operating environment)

Gaps and what would be needed to address them (arterial ITS, additional freeway technology infrastructure, operational processes, connectivity among agencies, transit, and additional Traffic Incident Management focus to support ICM)

Gaps, potential benefits, and operations under the “full build out” scenario by modeling the I‐10 corridor under different operating environments

Evaluation needs and performance reporting requirements for ICM strategies

Preliminary design documentation including:

Additional infrastructure

Funding requirements

Strategies for dissemination of traveler information (including smartphone apps that do not interfere with driving)

Software operating requirements and enhancement to ADOT Freeway Management System (FMS) centralized software

Process for initiating construction in 2014/2015

Plan to implement the necessary staffing, training, and resource needs for each involved agency Source: Chapter 6. Implementation Strategy in Integrated Corridor Management Plan, AZTech Strategy Task Force for MAG ITS Committee,

May 1, 2012, p. 22.



the cost to construct one new lane of freeway at costs ranging from $2.4 million to $6.9 million per lane-mile and higher, traffic management strategies indeed are a bargain. According to the FHWA:

At its most fundamental level, highway congestion is caused by the lack of a mechanism to efficiently manage use of capacity [emphasis added]. When searching for a solution to the congestion problem, most people immediately think of adding a new lane to an overburdened highway. Construction costs for adding lanes in urban areas average $10–$15 million per lane mile.2 In general, the funding for this type of construction comes from taxes that drivers pay when buying gas for their vehicles. Overall, funds generated from gas taxes on an added lane during rush hours amount to only $60,000 a year (based on 10,000 vehicles per day during rush hours, paying fuel taxes amounting to about 2 cents per mile). This amount is grossly insufficient to pay for the lane addition. The bargain price paid by motorists for use of an expensive new capacity encourages more drivers to use the expanded highway.10

This conclusion is presented in support of congestion pricing, a strategy employed to increase the cost of using existing transportation infrastructure and, thereby, encourage the use of other modes (e.g., carpools, transit, etc.).11 Nevertheless, the inability “…to efficiently manage the use of capacity” clearly is relevant to the discussion of automoated ATM, ICM, and ITS strategies that offer communities the opportunity to improve both the efficiency and safety of roadway system operations.

10 “Congestion Priciing – A Primer: Overview,” Tolling and Pricing Program, Federal Highway Administraiton (FHWA), August 2, 2013 at

http://ops.fhwa.dot.gov/publications/fhwahop08039/cp_prim1_02.htm. The footnote reference in the quote is: Federal Highway Administration. (2000). Highway economic requirements system (HERS) report (Tech. Rep. Vol. 4). Washington, DC. (Updated based on construction cost index.)

11 Managed Lanes employ the congestion pricing strategy to regulate entry ensuring traffic flow is consistent with the capacity of the facility.

FIGURE 11 EXAMPLE OF ACTIVE TRAFFIC MANAGEMENT SCREENING

Documents

active traffic management