Traffic Signal System Improvement Program 2007 update summary report

Transcription

1 Traffic Signal System Improvement Program 2007 update summary report

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3 Traffic Signal System Improvement Program 2007 Update Summary Report Adopted May 16, 2007 Denver Regional Council of Governments 4500 Cherry Creek Drive South, Suite 800 Denver, Colorado Preparation of this report has been financed in part through grants from the U.S. Department of Transportation

4 Disclaimer: The data in this report are compiled from multiple sources and are intended for informational purposes only. DRCOG assumes no responsibility or legal liability for the accuracy, completeness or usefulness of any information in this report. ii

5 TABLE OF CONTENTS EECUTIVE SUMMARY... 1 Background... 1 Implementation Plan... 1 Capital Improvements to Signal Systems... 1 System Engineering and Design... 2 Special Projects... 3 Contingency and Miscellaneous Equipment Purchases... 3 Timing and Coordination... 3 Benefits and Result Documentation... 3 I. INTRODUCTION... 5 Background... 5 Progress... 6 Update Process II. SYSTEM INVENTORY State of the Current Environment Communication Systems Detection Signal Coordination System Control Strategies Timing Plans Additional Highlights III. NEEDS ASSESSMENT Overview Call for Projects City of Aurora City of Boulder CDOT Region City and County of Denver (1) City and County of Denver (2) Douglas County (1) Douglas County (2) City of Lakewood City of Thornton Special Project (1) Special Project (2) Regional Performance Measures for Traffic Signal Operations Project Description Timing and Coordination on Key Corridors Summary of Critical Needs iii

6 IV. IMPLEMENTATION Overview Funds Available Prioritization and Implementation Rationale Implementation Program Elements Capital Program System Engineering and Design Contingency and Miscellaneous Equipment Purchases Signal Timing and Coordination Studies DRCOG Traffic Operations Program Responsibilities Benefits and Program Effectiveness BOARD RESOLUTION iv

7 List of Tables Table E-12 Signal System Capital Improvement Projects... 2 Table 1 Traffic Operations Improvement Summary Table 2 Traffic Signal Inventory within the Transportation Management Area.. 18 Table 3 Controller Types and Signal Systems Table 4 System Communications Media Table 5 Coordination Methods Table 6 Snapshot of Operating Agencies Table 7 Summary of Critical Needs Table 8 Funding for Implementation Program ($1,000) Table 9 Signal System Capital Improvement Projects List of Figures Figure 1 Transportation Management Area... 6 Figure RTP TMA Major Regional and Principal Arterial Roads... 9 Figure 3 TSSIP Projects Completed June 2003 Present Figure 4 Video Detector Figure 5 A Computer/Simulation Model for Signal Simulation v

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9 EECUTIVE SUMMARY Background The Denver Regional Council of Governments (DRCOG) administers the federallyfunded pool project titled Regional Traffic Signal System Improvement Program or TSSIP. The purpose of TSSIP is to implement cost-effective traffic signal timing and coordination improvements that reduce travel time and harmful auto emissions within the DRCOG Transportation Management Area (TMA). There are now more than 3,500 traffic signals maintained and operated by 32 different jurisdictions within the TMA. The TSSIP was originally adopted in 1994 and has been updated in 1996, 1999, and 2003 corresponding with funding authorized in the Transportation Improvement Program (TIP). Since the last update, the TSSIP has assisted 16 operating agencies in these efforts and completed capital improvement projects for 55 arterial roadway sections. The program also completed 19 timing and coordination projects and four traffic responsive control (TRC) projects during this period. These projects improved operations for more than 1,100 traffic signals throughout the region and reduced delay by nearly 36,000 vehicle-hours per day, reduced fuel consumption by more than 15,000 gallon per day, and reduced air pollution emissions (mainly carbon monoxide) by more than 45,000 pounds per day. Implementation Plan This TSSIP examines progress, assesses results, and updates the program of capital improvements for It recognizes recent changes to the regional traffic signal system made by local jurisdictions and the Colorado Department of Transportation (CDOT). To further improve the operations of the regional traffic signal system, the TSSIP will continue to pursue the following activities. Capital Improvements to Signal Systems a. Upgrade and replace insufficient/unreliable communications for more than 25 corridors (330 signals) b. Expand the system control to key signals not on a system for more than 12 corridors/areas or projects (160 signals) c. Improve the efficiency of signal system control in four jurisdictions Table E-1 shows the location of the capital projects of the implementation plan and the year(s) those projects are proposed for implementation. 1

10 Table E-1 Signal System Capital Improvement Projects Project/Description/Location FY08 FY09 FY10 FY11 FY12 Insufficient or Unreliable System Communication Aurora Iliff,Evans,Jewell,Quincy Buckley/Airport,Mississippi, Hampden,Alameda Peoria,6th,Smoky Hill, Parker Rd. Tower/Reservoir,Havana, Colfax,Arapahoe CDOT Region 6 SH 391/Kipl., 32nd - I-70 SH 287, 10th (Broomfield) - SH 7 (Lafayette) SH 7, SH I-25 SH 72, I th Highlands Ranch, Fairview - Douglas County Broadway; Broadway, Highlands Ranch - Dad Clark Key Signals Not on System Denver Cheesman Park -- bounded by 6th,12th,Grant,Jackson & plus Lower Core -- bounded by 1st,I-25, Lincoln,Monroe Monaco, Cornell - Leetsdale; Mississippi, Valencia - Dayton; Alameda, Dahlia - Fulton & plus Upper Core -- bounded by 24th, 40th,Steele,Arkins; 38th, Federal - Lipan Thornton Washington, 83rd - 103rd; Thornton Pkwy, Civic Ctr - Grant Efficiency Improvement and Special Projects Boulder Upgrade comm./system to IP/Ethernet Denver Regional Center to Center Communications Next Gen. System replacement/upgrade Douglas County Upgrade comm./system to IP/Ethernet Lakewood Upgrade comm./system including IP/Ethernet Performance Measures Study DRCOG Santa Fe/Broadway Performance Measures Pilot Corridors + other potential Implementation sites Retime Denver CBD Denver Contingency and Miscellaneous Equipment Reserve (Transit Signal Priority) Estimated Expenditure (2008 constant $) $2,613,000 $2,560,000 $2,325,000 $2,025,000 $2,260,000 Estimated Expenditure (year-of-expenditure $) ** $2,613,000 $2,638,500 $2,732,000 $2,437,000 $2,330,000 ** A 3% inflation rate is assumed for each year after FY08. 2

11 System Engineering and Design The TSSIP funds system studies and design activities required for the capital projects identified, as well as coordination with regional transportation management and intelligent transportation system (ITS) planning efforts. Special Projects The TSSIP will implement three special projects: Transit Signal Priority (continue from the last update), Denver Central Business District (CBD) signal timing (more than 200 traffic signals), and the development of regional performance measures for traffic signal system operations Contingency and Miscellaneous Equipment Purchases These funds ensure that projects can proceed to construction if actual costs exceed the conceptual estimates developed for this update. Once it is certain that identified construction projects can progress, remaining contingency funds are used for miscellaneous traffic signal equipment purchases. To a limited extent this allows capital projects from later years of the program to be advanced, funds critical needs that had to be deferred to stay within the budget, and provides a way to address evolving needs in response to growth and development. Timing and Coordination This fundamental part of the program anticipates continued development of new time-of-day (TOD) schedule-based timing plans on a recurring basis in a three- to five-year cycle or as needed for major corridors and for all capital projects implemented (including miscellaneous signal equipment purchases). Some additional funds will be targeted for selectively developing TOD plans that address weekend traffic patterns. Development and evaluation of timing plans for traffic responsive control (TRC) achieved successful results in the past few years through trial projects and will now be included as they arise. Benefits and Result Documentation Determining and documenting the benefits and effectiveness of currently ongoing and programmed projects is critical to this program update. Because the TSSIP is funded with federal Congestion Mitigation/Air Quality (CM/AQ) funds, the benefits of every project must be measured and reported. The program s primary documentable benefits result from the regular retiming of major arterials. Drivers, passengers, truckers, service vehicles, bicyclists and pedestrians all reap the benefits of improved signal timing and coordination. Fewer stops and less delay save time, money, and reduce air pollution for everyone. Based on the past efforts, travel times on individual corridors are expected to be reduced by 5 to 15 percent after a retiming project. TRC projects implemented in the region have produced 2 to 4 percent travel time benefits. 3

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13 I. INTRODUCTION Background The Denver Regional Council of Governments (DRCOG) administers the federallyfunded pool project titled Regional Traffic Signal System Improvement Program. It is identified in the Transportation Improvement Program (TIP) as project ID # This project is directed by the Traffic Signal System Improvement Program (TSSIP) adopted by the DRCOG Board of Directors. The purpose of TSSIP is to implement cost-effective traffic signal timing and coordination improvements that reduce travel time and harmful auto emissions within the DRCOG Transportation Management Area (TMA, see Figure 1.) This program was originally adopted in 1994 and has been updated in 1996, 1999, and 2003, corresponding with funding authorized in the following TIPs. TSSIP Corresponding TIP 1994 Original and update and update and update and This TSSIP examines progress, assesses results, and updates the program of capital improvements for It recognizes recent changes to the regional traffic signal system made by local jurisdictions and the Colorado Department of Transportation (CDOT). In addition, the program was reassessed regarding implementation of Transit Signal Priority, traffic data collection, and coordinated corridor management and operations. 5

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15 Progress Since the last update (2003), the program has continued to assist stakeholders in implementing new traffic signal control systems or extending and/or upgrading system communications to enhance traffic signal operations at key signals. Key signals are those located on major regional arterials and principal arterials defined in the 2030 Metro Vision Regional Transportation Plan OR in the Denver Central Business District (CBD) core area bounded by I-70, I-25, and Colorado Boulevard (see Figure 2). Since 2003, the program has assisted 16 operating agencies in these efforts and completed capital improvement projects for 55 arterial roadway sections. The program also completed 19 timing and coordination projects and four traffic-responsive control (TRC) projects during this period. These projects improved operations for more than 1,100 traffic signals throughout the region and reduced delay by nearly 36,000 vehiclehours per day, reduced fuel consumption by more than 15,000 gallon per day, and reduced air pollution emissions (mainly carbon monoxide) by more than 45,000 pounds per day, as shown in Table 1. The project locations are displayed in Figure 3. 7

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18 Table 1: Traffic Operations Improvement Summary Capital Project Year Completed From To Number of Signals Average Daily Traffic Corridor Travel Time Decreases (veh-hrs/day) Benefits Fuel Consumption Reduction (gl/day) Air Pollutant Emission Reduction (lb/day) User Savings ($/day) Speer Boulevard nd Ave Zuni St 6 53, ,100 Sheridan Boulevard th Ave Alameda Ave 21 44, ,600 Westminster Mall Arterials various 1, ,437 18,550 South Boulder Road 2003 McCaslin Blvd Plaza Dr 8 26, ,200 Parker Arterials various 2, ,722 33,850 Castle Rock Area various ,450 Colfax Avenue 2003 Welch St Eliot St 22 35,000 1, ,316 17,450 McCaslin Blvd 2003 Centennial Pkwy Rock Creek Pkwy 8 38, ,250 Flatiron Crossing Mall Area , ,050 US Arapahoe Rd Niwot Rd 5 26, ,250 Arapahoe Road (SH-7) rd St US , ,100 Longmont Arterials various n/a n/a n/a n/a Wadsworth Blvd 2004 Yale Ave 20th Ave 18 45, ,150 Parker Road 2004 Chambers Rd Iliff Ave 16 62, ,650 East Boulder Arterials various 1, ,702 27,100 Colorado Blvd 2004 Ohio Ave 48th Ave 30 63,000 1, ,235 19,550 Union Blvd/Simms St 2004 Green Mtn Dr Kipling St 8 62, ,250 Alameda Pkwy/Alameda Ave 2004 Alameda Ave Colfax Ave 9 29, ,400 Van Gordon Street 2004 Cedar Dr 4th Ave 5 14, Quebec Street 2004 I-70 72nd Ave 8 20, ,500 Commerce City Arterials various , th Avenue 2004 Pecos St Nickel St 9 40, ,450 Sheridan Blvd th Ave Midway Blvd 9 35, ,850 Sheridan Blvd nd Ave 76th Ave 11 43, ,250 Peoria Street 2004 Mississippi Ave Del Mar Cir 6 16, ,350 University Blvd (SH-177) 2004 Dad Clark Dr Hampden Ave 14 39, ,250 Diagonal Highway Arterials 2005 Jay Rd Niwot Rd 14 57, ,500 Park Avenue 2005 Franklin St Tremont Pl 10 18, ,050 17th Avenue/18th Avenue 2005 Washington St Steele St 27 17, ,064 7, th Avenue 2005 Pecos St Holly St 22 50, ,200 Arapahoe Road 2005 Havana St Buckley Rd 9 60, ,850 Parker Road 2005 Arapahoe Rd Chambers Rd 4 66, ,022 20,050 Washington Street th Ave 136th Ave 11 26, ,700 Broadway 2005 Dad Clark Dr Tufts St 34 48, ,500 Federal Blvd th Ave 120th Ave 25 63, ,500 N. Colorado Blvd th Ave 124th Ave 11 27, ,600 Bowles Avenue 2005 Grant Ranch Blvd Santa Fe Dr 8 42, ,850 State Highway Colfax Ave Golden Gate Canyon Rd 10 24, ,000 72nd Avenue 2005 Indiana St Kipling St 8 15, ,450 64th Avenue 2005 Quaker St Ward Rd 9 30, ,100 Ward Road 2005 I-70/44th 64th/Ward Rd 8 34, ,500 Indiana Street th Ave 86th Ave 4 18, ,450 County Line Road * 2005 Quebec St Chester St 6 16,000 n/a n/a n/a n/a Quebec Street * 2005 County Line Road University Blvd 7 22, ,700 University Boulevard * 2005 County Line Road Quebec St 13 22, ,400 Evans Avenue 2006 Tennyson St Broadway 13 35, ,350 Jewell Avenue 2006 Sheridan Blvd Bear Creek Blvd 14 20, ,800 Bear Creek Boulevard 2006 Morrison Rd Jewell Ave 5 13, ,350 1st Ave/Steele Steet 2006 Cherry Creek Dr N University Blvd 10 57,000 1, ,258 22,400 University Boulevard 2006 Cherry Creek Dr S 4th Ave 9 43, ,800 Speer Boulevard 2006 Gilpin St Colfax Ave 32 50, ,400 MLK Boulevard 2006 Downing St Colorado Blvd 16 15, ,350 Colfax Avenue, East 2006 Broadway Sable Blvd 55 37,000 1, ,400 Santa Fe Drive 2006 Mississippi Ave Highlans Ranch Pkwy 21 40,000 3,112 1,661 5,670 62,900 Hampden Avenue ** 2006 University Ave Dartmouth Ave 21 72,000 1, ,150 Subtotal ,365 11,884 35, ,550 Timing/Coordination Project Kipling Street 2003 Exposition Ave Belleview Ave 16 45, ,050 38th Avenue 2003 Wadsworth Sheridan Blvd 8 17, ,350 Lincoln Avenue 2004 Yosemite St Peoria St 9 36, ,800 Monaco parkway 2004 Cornell Ave Smith Rd 30 30,000 1, ,638 26,400 Leetsdale Drive 2004 Forest St Mississippi 7 50, ,750 Quebec Street th Ave 36th Ave 9 46, ,350 Cherry Street 2004 Mississippi Leetsdale Dr 6 13, ,200 Arapahoe Road 2004 Franklin St Homestead 8 31, ,950 Alameda Avenue 2004 Dahlia St Galena Way 11 40, ,100 Downing Street th St Walnut St 15 11, ,450 State Highway Lock St South Boulder Rd 4 18, ,350 Smoky Hill Road 2006 Quincy Ave Arapahoe Rd 23 20, ,900 Meadows/Founders Pkwy 2006 Meadows Blvd Crawford Valley Rd 13 39, ,500 Broadway/Lincoln 2006 Center Ave 13th Ave 35 30,000 1, ,201 37,750 Santa Fe Dr & Kalamath St 2006 Cedar Ave Colfax Ave 16 35, ,700 6th Ave & 8th Ave 2006 Logan St Kalamath St 22 35, ,850 Jordan Road 2006 Lincoln Ave Arapahoe Rd 14 24, ,700 State Highway McCaslin Blvd Airport Way 7 20, ,100 Belleview Avenue 2006 Lowell Blvd Pirate's Cove 7 39, ,050 Subtotal 260 8,601 3,501 9, ,300 Total ,966 15,385 45, ,850 Traffic Responsive Control Project Westminster Mall TRC veh-hrs/wk 218 gl/wk 498 lb/wk $5,750/wk Union/Simms TRC veh-hrs/wk 42 gl/wk 115 lb/wk $1,800/wk Parker Road TRC 2005 I-225 SB ramp Iliff Ave veh-hrs/wk 191 gl/wk 566 lb/wk $6,500/wk Coors Field TRC veh-hrs/game 26 gl/game 66 lb/game $650/game * Signal timing improvement conducted by Douglas County staff. ** Includes 11 signals on Logan Street.

19 66 Hover St Main St 3rd Ave Ken Pratt Blvd Figure 3 TSSIP Projects Completed June Present Iris Ave Jay Rd 63rd St 42 Baseline Rd Arapahoe Ave South Boulder Rd 7 McCaslin Blvd NWP E th Ave Flatiron Cir Huron St Washington St Colorado Blvd 120th Ave th Ave Indiana St 88th Ave 72nd Ave 64th Ave Ward Rd Colfax Ave Wadsworth Blvd Alameda Ave Sheridan Blvd Federal Blvd 38th Ave 6 Thornton Pkwy 2 88th Ave 84th Ave 72nd Ave Speer Blvd Downing St Vasquez Blvd Monaco Pkwy Quebec St Martin Luther King Blvd Alameda Ave Bear Creek Blvd C-470 Kipling St Jewell Ave Hampden Ave Bowles Ave Evans Ave Santa Fe Dr Broadway 25 University Blvd Colorado Blvd County Line Rd Quebec St Peoria St Arapahoe Rd 225 E-470 Parker Rd Jordan Rd Smoky Hill Rd 88 Lincoln Ave Mainstreet Meadows/Founders Pkwy Franktown Rd 83 Source: DRCOG Projection: Colorado State Plane, NAD 83 MN Miles This map and the data it depicts are intended for informational purposes only. DRCOG provides this information on an "as is" basis and makes no representation or warranty that the data will be error free. DRCOG is not responsible to any user for any costs or damages arising from inconsistencies in its data. Capital Improvement Timing/Coordination Traffic Responsive Control Area Outside Region ±

20 Several capital improvement projects are nearing completion or in progress for system equipment and communications upgrades and timing/coordination improvements: Quebec Street (Denver) DTC area arterials (Denver, Greenwood Village, and CDOT) University Boulevard (Douglas County) Wadsworth Boulevard (CDOT and Lakewood) US-6 (Denver and Lakewood, incident management operations) One additional traffic-responsive control (TRC) project is in progress on Hampden Avenue (Englewood). The Park Meadows Mall area (Douglas County) TRC project was postponed indefinitely due to a system communication problem that has not been resolved. DRCOG continues to work in partnership with the Regional Transportation District (RTD), Boulder, and Denver regarding Transit Signal Priority for five test implementation sites selected by the stakeholders. A study report will be completed in 2007, with test implementations forthcoming. Update Process A work group with representation from traffic signal operating agencies, RTD and Federal Highway Administration (FHWA) was assembled to assist in the TSSIP update effort. The work group was extensively involved in the update process, including verifying current conditions, identifying critical needs, and working in separate task force groups regarding new issues (TSSIP funding of staff and performance measures for traffic signal management and operations). Two stakeholder meetings and two task force group meetings were held between August 2006 and January

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22 II. SYSTEM INVENTORY State of the Current Environment A survey questionnaire was sent to each operating agency to provide updated information regarding signal system inventory and traffic signal operations. The information received was reviewed by the DRCOG staff and compiled into five tables presented in this chapter to illustrate the current condition and state of the operations in the region. There are now more than 3,500 traffic signals (9 percent increase from 2003) maintained and operated by 32 different jurisdictions within the Denver TMA. Nearly 2,600 of these signals (18 percent increase from 2003) are considered key signals. In addition, more than 1,940 key signals are currently connected to a traffic signal control system (27 percent increase from 2003). All agencies that have key signals and more than 20 signals to operate have a signal control system. Table 2 summarizes the traffic signal inventory in the region. All systems in operation meet the six base-level system requirements listed below. Several agencies initially responded that their systems do not meet certain base-level function(s). However, after some follow-up interviews, it was clarified that the systems actually do have those functions but the operating agencies are not able to utilize one or more functions due to various institutional/communication limitations. The base-level traffic signal control requirements are: Automatic synchronization to Universal Coordinated Time; Upload/download of timing/coordination parameters; Real-time monitoring of system and intersection operation; Error detection and automatic reporting; Back-up time-based coordination (TBC) operation; and Remote access to system databases. All TSSIP capital projects are prepared and implemented with the goal of fulfilling these functions and making the signal operations in the region more reliable. Since the last update, the TSSIP projects included the installation of a new traffic signal control system in Thornton and an upgrade of a closed-loop system in Westminster with a more robust central system. Lakewood s conversion from its VMS system to Series 2000 system is now complete. Boulder is replacing all its Type 170 traffic signal controllers with Type 2070, a more diverse and robust set of equipment, to maximize efficiency and effectiveness of its control system. The only operating agencies in the region currently without a system are those with fewer than 20 signals to operate. These are Brighton, Federal Heights, Golden, and Sheridan. Boulder County has a closed-loop system (Aries) but it is not in operation due to a failed dial-up/cell communication system. Several other smaller jurisdictions have an intergovernmental agreement (IGA) transferring the operations responsibilities 17

23 to larger neighbors, including Centennial (IGA with Arapahoe County), Glendale (IGA with Denver), and Lone Tree (IGA with Douglas County). Table 2 Traffic Signal Inventory within the Transportation Management Area Operating Agency 2003 Totals Number of Signals 2006 Number of Key Signals Number of Key Signals on System (5) Adams County Arapahoe County (1) Boulder County Douglas County (2) Jefferson County Arvada Aurora Boulder Broomfield Brighton NA Castle Rock Commerce City Denver (3) 1,242 1,263 1, Englewood Federal Heights Golden Greenwood Village Lafayette Lakewood Littleton Longmont Louisville Northglenn Parker (4) Sheridan Superior Thornton Westminster Wheat Ridge CDOT R1 (4) CDOT R CDOT R Total 3,236 3,541 2,567 1,944 (1) Centennial signals included 9% increase from 2003 (2) Lone Tree signals included (3) Glendale signals included (4) 13 signals on Parker Road moved from Region 1 system to the Town of Parker system (5) 76% of Key Signals are on system 18% increase from % increase from

24 Table 3 summarizes the type of controllers and various traffic signal control systems being used in the region. Table 3 Controller Types and Signal Systems Operating Agency Controller Type Signal System Type Adams County NEMA (1) Econolite Aries Arapahoe County NEMA Econolite Aries Boulder County NEMA and 170 Econolite Aries (2) Douglas County 170 Econolite Pyramids Jefferson County 170 Econolite Translink 32 Arvada NEMA Econolite Aries Aurora NEMA Eagle Actra Boulder 170/2070 Econolite Pyramids Broomfield 170 Econolite Translink 32 Brighton NEMA None Castle Rock 170 Econolite Translink 32 Commerce City NEMA Eagle Marc N Denver NEMA Econolite Icons, Aries and Transyt Smartways Englewood NEMA Econolite Icons Federal Heights 170 None Golden 170 None Greenwood Village 170 TCS-II Lafayette NEMA Eagle Marc N Lakewood NEMA Transcore Series 2000 Littleton NEMA Econolite Icons Longmont NEMA Econolite Aries Louisville NEMA Econolite Aries Northglenn NEMA Econolite Aries Parker 170 Econolite Translink 32 Sheridan NEMA None Superior 170 Econolite Translink 32 Thornton 170 Econolite Pyramids Westminster NEMA Econolite Icons Wheat Ridge NEMA Econolite Aries CDOT R1 170 Econolite Pyramids CDOT R4 170 Econolite Translink 32 CDOT R6 170 Econolite Pyramids (1) National Electrical Manufacturers Association (NEMA) (2) Currently not in operation 19

25 Communication Systems A reliable communications network is an important component of a complete traffic control system, as it provides the connection between the field equipment and the traffic signal control system. Lacking such communications, a traffic control system is not very functional. The communication element of a traffic signal control system provides for the movement of data from the local intersections to the point of control (be it a central computer, a master controller, or the responsible engineer or technician) and the movement of commands from the point of control to the local intersections. System communications used by the operating agencies are now mainly via fiber optic networks, spread spectrum radio networks, leased phone line services and some remaining agency-owned copper wire. Within individual systems, signal communications is mostly achieved through a combination of spread spectrum radio and fiber optic networks. Packet radios with a licensed frequency are still in use by CDOT Region 6 at some of its signals. Some agencies have implemented or are implementing IP/Ethernet based communication for traffic signal system control. A few agencies are also checking the possibility and potential of using WiFi networks for signal communications if available in their areas. The upgraded communication network has provided a higher level of reliability for traffic signal operations. It has also provided an improved coverage and firm support for existing and future ITS applications. Table 4 identifies the communications media currently used in the region. 20

26 Operating Agency Adams County Arapahoe County Boulder County Douglas County Jefferson County Arvada Aurora Boulder Broomfield Brighton Castle Rock Commerce City Denver Englewood Federal Heights Golden Greenwood Village Lafayette Lakewood Littleton Longmont Louisville Northglenn Parker Sheridan Superior Thornton Westminster Wheat Ridge CDOT R1 CDOT R4 CDOT R6 Table 4 System Communications Media Communications Media Agency-owned hardwire and cell phone Agency-owned hardwire, spread spectrum radio, fiber and leased telephone network None (system not in operation) Agency-owned fiber and spread spectrum radio Agency-owned spread spectrum radio and leased telephone network Agency-owned spread spectrum radio, fiber and hardwire Leased telephone network, agency-owned hardwire and spread spectrum radio Agency-owned spread spectrum radio and leased telephone network Agency-owned fiber, spread spectrum radio and some packet radio None Agency-owned fiber, spread spectrum radio and hardwire Spread spectrum radio Agency-owned fiber, spread spectrum radio and hardwire Agency-owned hardwire, fiber and spread spectrum radio None None Agency-owned fiber Agency-owned spread spectrum radio Agency-owned fiber, spread spectrum radio and leased telephone network Agency-owned spread spectrum radio and fiber Leased telephone network Agency-owned hardwire Leased telephone network Agency-owned fiber and spread spectrum radio None Agency-owned fiber and spread spectrum radio Agency-owned fiber and spread spectrum radio Agency-owned fiber, hardwire and spread spectrum radio Agency-owned fiber, hardwire and leased telephone network Agency owned fiber, hardwire and spread spectrum radio Agency-owned spread spectrum radio Agency-owned fiber, hardwire and packet radio 21

27 Detection Detection refers to that component of the traffic signal system used to: Inform signal controllers at local intersections of the presence of vehicles or pedestrians that need to be served, and Measure and monitor traffic, either for information purposes or for advanced system control strategies. Most operating agencies are now using a combination of inductive loops and video detectors as their main detection equipment for traffic signal operations. An inductive loop detector is wire installed in the pavement to register changes in an electromagnetic field when a vehicle is present. Video detection (Figure 4) uses a video camera to capture image variation on the roadway to provide the traffic detection. Some of these detectors are also being used for traffic counting or system detection (mainly for traffic-responsive control) purposes. Figure 4 Video Detector Signal Coordination Coordination is the process of making signals work together (Figure 5), as opposed to independently. Signal timing plans are prepared for groups of traffic signals to reduce drivers delay and stops as they progress through the street network. There are two primary methods to accomplish coordination: signal system and timebased. In a signal system, traffic signals are linked together by a communications network and various control functions are governed by a master controller or a central computer. If the communication network is functional, system control is a very reliable form of coordination. Time-based coordination (TBC) relies on synchronizing time clocks installed with or within the controllers at individual intersections. A communication network is not specifically required to provide TBC. This form of coordination requires substantial effort to assure the time clocks stay in synch, and is a much less reliable form of coordination. 22

28 Figure 5 A Computer/Simulation Model for Signal Simulation The TSSIP projects included traffic signal coordination across jurisdictional boundaries by having all controllers and control systems synchronized with the Universal Coordinated Time (WWV time) broadcast by National Institute of Standards and Technology (NIST) in Boulder. Table 5 identifies the coordination methods used by each jurisdiction and the number of signals included. 23

29 Operating Agency Coordinated Signals System TBC * Uncoordinated Signals Totals Adams County Arapahoe County Boulder County Douglas County Jefferson County Arvada Aurora Boulder Broomfield Brighton Castle Rock Commerce City Denver ,263 Englewood Federal Heights Golden Greenwood Village Lafayette Lakewood Littleton Longmont Louisville Northglenn Parker Sheridan Superior Thornton Westminster Wheat Ridge CDOT R CDOT R CDOT R Total 2, ,541 * Time-based Coordination Table 5 Coordination Methods 24

30 System Control Strategies System control strategies for coordination can be subdivided into three categories: timeof-day (TOD), traffic-responsive control (TRC), and traffic-adaptive control (TAC). Under the TOD strategy, timing plans are developed based on historical information to address typical traffic conditions during several different periods of the day (for example, morning peak and afternoon peak), and the appropriate plan is implemented on the basis of the time of day and day of week (for example, the afternoon peak plan is operated every weekday from 3 p.m. to 7 p.m.). Under TRC, timing plans are also developed off-line based on historical information, but the signal system implements specific timing plans based on detected traffic conditions instead of a TOD schedule. This control strategy helps address circumstances such as special events and incidents as well as day-to-day variability in traffic patterns. TAC is the most complex of the control strategies; timing plans are developed and implemented in real-time based on detected real-time traffic conditions in the field. TOD control is the predominant type of control strategy currently used in the region. Traffic-responsive control (TRC) has been implemented and considered beneficial in areas experiencing variable traffic patterns. Four traffic-responsive control operations (Parker Road near I-225 in Aurora, Coors Field in Denver, Union/Simms corridor in Lakewood, and the Westminster Mall area in Westminster) were implemented since the last TSSIP update. TRC is no longer considered a trial application (referred to in the past as test beds ). When traffic conditions vary on a day-to-day basis without stable time-of-day traffic patterns, operating agencies in the region consider TRC as an effective control strategy. TAC is not yet implemented anywhere in the region, but Broomfield and Denver are considering its implementation. Timing Plans Through the TSSIP, DRCOG has facilitated coordination of traffic signals across jurisdictional boundaries, with an objective of retiming signals on major roadways every three to five years when applicable. Operating agencies also devote resources to corridor retiming (staff or consultants). In general, during weekdays, most corridors are coordinated using three TOD timing plans (morning peak, afternoon peak and all other times). Several agencies now use two plans for the non-peak period, a timing plan for the few hours during lunch time and another one (with a shorter cycle length) to cover the low-volume off-peak periods. On weekends, many corridors still use afternoon peak or all other times plans. DRCOG timing projects, over the last few years, are now providing specific weekend plans. This practice will be continued where feasible and applicable. 25

31 Additional Highlights The following highlights drawn from the survey questionnaires reflect the current state of the operating agencies. Table 6 provides a snapshot of these operations. Nine operating agencies reported having some type of real-time data collection. The data was used for traffic-responsive control, volume monitoring, signal timing analysis, and public information purposes. Most operating agencies with signal systems have functional capabilities beyond base-level control (i.e. traffic-responsive control and transit signal priority). However, many of these systems would need upgrades in traffic or transit bus detection to make these advanced functions operational. More than half of the operating agencies (18) reported interest in possibly implementing transit signal priority (TSP). A TSP study currently in progress recommends implementing TSP operations on test sites/corridors in two locations (Boulder and Denver). Four agencies, Aurora, Denver, Lakewood, and Northglenn, have traffic-responsive control (TRC) in operation (on Parker Road near I-225, in Coors Field area for ballgame traffic, on Union/Simms corridor near 6 Avenue, and on 104 th Avenue near I-25, respectively). Westminster had operated TRC in the area near Sheridan Boulevard and US-36. The signals are now temporarily operating in TOD mode due to a signal control system upgrade. Westminster replaced its closed-loop system with a more robust central system. The operating agencies are sufficiently satisfied with the control strategy in the specific areas/corridors. More than two-thirds of the agencies (22) reported interest in having inter-agency communication (mostly at the data-sharing level). Control sharing will be evaluated as a part of the Santa Fe Drive/US-85 incident management project. In addition, Denver and Aurora are currently evaluating a potential conditional center-to-center control sharing opportunity that may benefit the DIA incident management operation. Most agencies (21), reported having only one engineer for traffic signal operations. These engineers are also usually responsible for other transportation engineering services. Signal operations in the smaller agencies are usually the responsibility of the city engineer or public works director. Most mid-sized and large agencies have technician staff and contract services to support operations. Most small agencies use contractors to support operations. 26

32 Fewer than one-fourth of the agencies (7) reported a staff assignment to some level of real-time monitoring of their signal system and operations. Only one of these agencies committed at least 75 percent of one staff person s time to doing so. More than one-third of the agencies reported that the traffic operations center is either the engineer s office or they have no operations center. Five agencies reported having their traffic operations center in the signal maintenance facility or shared space with other functions. Only a few of the larger operating agencies (Douglas County, Denver, and Lakewood) have dedicated traffic operations centers. Commerce City reported that construction of a dedicated traffic control center will be complete and operational by June

33 Table 6 Snapshot of Operating Agencies Number of Signals Utilize real time data collection Real Time data collection Engineers and Time Spent working with signals For what purpose? Types of detection How many have a signal system Signal system meets base-level functionality Advanced functional capabilities in the signal system Interested in implementing conditional transit signal priority Interested in inter-agency communication # of Engineers (ER) % time spent working with signals Range of signals to engineers ratio NA 2 to 1-25 to 1 Name of Jurisdiction < Video (5) 6 5 Transit Priority (4) ER (2) --- Loop (10) 1 ER (8) 2-10% TRC, Video (13) TRC (4) ER (8) 10-65% Timing/Split analysis, Loop (13) Video Monitoring (1) 2 ER (2) 25-30% outside agency requests Microwave (1) Transit Priority (5) 3 ER (3) 15-30% TRC, Video (6) 6 6 TRC (4) ER (3) 5-75% Loop (6) Transit Priority (5) Possibly (1) 2 ER (2) 30-60% 3 ER (1) 35% Timing/Split analysis, outside agency requests > TRC, Video (3) 3 3 TRC (3) ER (2) 40% Loop (3) Transit Priority (1) Possibly (1) Possibly (1) 7 ER (1) 60% Microwave (1) Timing/Split analysis, outside agency requests 10 to 1-79 to 1 46 to to to to 1 28

34 Table 6 (continued) Snapshot of Operating Agencies Number of Who maintains signals <25 Contractor (8) Combination (2) Technicians and time spent by operating agencies whose staff maintains its signals Real time monitoring by staff? Staff time spent monitoring the signals # of Technicians % Time Spent # of Staff % Time Spent Special events timing plans Time required to respond to and complete a timing change Dedicated operations center/room 1 tech (2) 25-50% Event (1) 1-3 days 1 Traffic Operations Center Shared room with other functions Engineer's Office Currently linked to CDOT/CDOT ITS Contractor (2) 1 tech (3) % 1 (4) Varies Holiday 1 day - 2 weeks Shop (2) Staff (5) 3 techs (1) 60% Church (1) Combination (6) 5 techs (1) 80% Event (2) 6 techs (1) 30% Contractor (1) 2 techs (1) 80% 1 5% Combination (5) 3 techs (1) 80% 1 Varies 5 techs (1) 80% 6 techs (2) 85% Event (4) 1 hour - several months >250 Staff (2) 7 techs (1) 70% 1 75% Event (2) 3 hours - 6 weeks 10 techs (1) 100% Holiday (1) Combination (1) 20 techs (1) 75% * Results based on received questionnaires and follow-up interviews

35 30

36 III. NEEDS ASSESSMENT Overview This part of the update process was performed to determine short-term needs in the region. A meeting was held in August 2006 for stakeholders to report and assess their signal system improvement needs. A call for projects process was initiated after the meeting to identify specific areas for capital improvements. In addition to various needs for capital improvements, two special items were noted for further development: 1) improved system management and operations by increasing staff for proactive system monitoring/management and enhanced repair/servicing; and, 2) establishment of a set of regional system performance measures. Two task force groups were assembled to discuss staff funding and performance measures. Based on ideas yielded from the group discussions, DRCOG staff developed a project proposal for regional traffic signal monitoring services which included a combined scope for staff funding and performance measures for traffic signal operations. However, during follow-up discussions with the stakeholders, the idea of using Federal funds for staff funding was not recognized as a critical need at this time. Development of regional performance measures for traffic signal operations was recommended as a critical need for inclusion in this update. Call for Projects Eight jurisdictions (Aurora, Boulder, CDOT Region 6, Denver, Douglas County, Englewood, Lakewood, and Thornton) submitted projects for various system improvements. Englewood withdrew its application due to the project s relatively small size and will consider resubmitting the project for future miscellaneous equipment purchase. After discussions with other applicants to clarify the details, the total funding request in this TSSIP update is estimated at approximately $16.4 million. This section summarizes the results of the call for projects. City of Aurora Replace and upgrade unreliable communications In this project Aurora will migrate from a leased communications network to an IP/Ethernet radio system. To maintain system compatibility, the existing Eagle EPAC 300 traffic signal controllers would need to be replaced with Eagle M51 traffic signal controllers and cabinets (including battery back-up/ups) at many locations. The main goal/justification of the project is to eliminate system downtime and related issues (i.e. clock drift), which would increase reliability. This project included 241 signals on 14 key corridors (Evans/Iliff/Jewell, Quincy, Buckley/Airport, Mississippi, Hampden, Alameda, Peoria, 6 th, Smoky Hill, Parker Rd., Tower/Reservoir, Havana, Colfax, and Arapahoe). Aurora proposes to complete this project through a phased four-year process. A design or Plan, Specification and Estimate (PS&E) package is not required for this project and the unit cost per signal location is relatively low. 31

37 City of Boulder Upgrade system beyond base-level signal control This project will upgrade existing controllers and communications with 2070 controllers (including battery back-up/ups) and an IP/Ethernet radio system. The main goal/justification is to provide higher-level signal system functions, including remote access to data/log/peripheral programming, enhanced lead/lag operation for signal progression, flashing yellow arrow operation, traffic-responsive control operation, and transit priority. The upgrade would also provide a more reliable timing operation by eliminating clock drift. This project includes 62 signals on eight key corridors (Foothills, 28 th, Arapahoe, Canyon, Pearl, Table Mesa, Baseline, and Iris/Diagonal) in Boulder. Boulder proposes to complete this project through a phased 4-year process. A design or Plan, Specification and Estimate (PS&E) package is not required for this project and the unit cost per signal location is relatively low. CDOT Region 6 Replace/upgrade unreliable communications This project will replace/upgrade existing unreliable radio communications with fiberoptic communications on seven key corridors (SH 391/Kipling, SH 287, SH 7, SH 72, SH 121, SH 88, and SH 128) for 56 traffic signal locations. The main goal/justification is to both eliminate continuous communication drops due to interference and improve reliability of timing operation. A design or Plan, Specification and Estimate (PS&E) package is required for each corridor/project and the unit cost per signal location is relatively high. City and County of Denver (1) Extend the reach of system control Denver requests to extend system control and replace outdated system equipment at key signal locations in the CBD Core area and on Monaco Parkway. A large portion of it is from the remaining projects in the TSSIP 2003 Update. The main goal/justification is to connect these signals to Denver s central control system and provide a base-level system control capability, coordination reliability, and system data collection/storage. The Denver application includes one key corridor (Monaco) and three areas in the CBD Core (Cheesman Park, Lower Core, and Upper Core) for approximately 170 traffic signal locations. A design or Plan, Specification and Estimate (PS&E) package would be needed for each corridor/project and the unit cost per signal location is considered moderate. City and County of Denver (2) Upgrade system beyond base level signal control This project is to upgrade system/it for regional center-to-center (C2C) communications at Denver s Traffic Management Center. The main goal/justification is to provide network security and higher level system capability that would support regional signal control, cross-jurisdictional incident management, regional traffic data sharing/warehousing as well as transit signal priority at the network level, adaptive 32

38 traffic signal control that integrate with existing detection capability, etc. A system upgrade study/report and a design package would likely be needed for this system upgrade. Douglas County (1) Replace/upgrade unreliable communications The main goal/justification is to provide base-level system control functions and coordination reliability. This part of the Douglas County application includes three key corridors (Lincoln, Highlands Ranch, and Broadway) for 33 traffic signal locations. A design or Plan, Specification and Estimate (PS&E) package would be needed for each corridor and the unit cost per signal location is considered high for the Lincoln corridor and moderate for the other two. Douglas County (2) Upgrade system communications This is a countywide project to upgrade from the existing serial communications system to an IP/Ethernet-based communications network. The main goal/justification is to provide more efficient usage of the existing communication bandwidth and, in some areas, increased bandwidth for a higher level of data transmission and system control. Although the county indicated that the upgrade would need a system design, it should be noted that other jurisdictions that requested similar system upgrades did not request a design. City of Lakewood Upgrade system beyond base-level signal control This project is to upgrade signal control system by replacing the Alpha Series Server, the communication server at its Traffic Management Center, and replace the existing serial communication network with IP/Ethernet compatible control equipment at the system and local level. The main goal/justification is to provide higher-level signal system functions and to proceed to the next level of advanced traffic management incorporating compatible regional C2C communications, cross-jurisdictional incident management, and regional traffic data sharing. A detailed system upgrade report was provided with the Lakewood application. Further study or design is not required. City of Thornton Extend the reach of system control This project is to extend Thornton s fiber-optic communications network to provide baselevel system control functions to key signals not yet on the system. It includes multiple sections on Washington Street, a section on the east end of 104 th Avenue, and a short section on Thornton Parkway for a total of 30 traffic signal locations. A design and Plan, Specification and Estimate (PS&E) package would be needed for each corridor and the unit cost per signal location is considered moderate to high. 33

39 Special Project (1) Transit Signal Priority Advanced function and regional test beds Transit (bus) priority is an operational strategy that facilitates the movement of in-service transit/bus vehicles through traffic signal-controlled intersections. It modifies the normal signal operation process to better accommodate transit vehicles to keep them onschedule with minimized delay. It may even permit RTD to reduce the scheduled travel time on some routes. As noted in the Regional ITS Plan, most of RTD s fixed bus routes use many of the roadways in the arterial network, and the existing arterial traffic signal system does not provide any kind of traffic signal priority treatment for buses. DRCOG, in partnership with RTD, is working on a Transit Signal Priority (TSP) study. The report will include a regional TSP strategy and functional/preliminary designs for the test bed sites identified in both Boulder and Denver. A detailed design (if needed) and system/equipment upgrades for Boulder, Denver, and RTD will follow. Funds in the current TSSIP will not be enough to implement and test TSP at the network control level which would heavily depend on the upcoming upgrade in RTD s transit management system. Additional funds are needed to implement the test bed projects identified in Boulder and Denver. Special Project (2) Retiming of Denver CBD Signal timing and coordination Denver reported that the downtown timing plans (200+ signals) need to be reevaluated and adjusted due to the anticipated additional downtown transit traffic including the potential operation of four-car light rail transit trains. The last Denver CBD retiming effort took about three years and was completed in 2003 by DRCOG. Because of its magnitude and complexity, this is a critical need from Denver as a special project for funds in TSSIP in Consultant assistance would be required for this project. Regional Performance Measures for Traffic Signal Operations Development of regional performance measures for traffic signal system operations that may be applied by all operating agencies in the region is identified as a critical need. Through the development process, regional goals and objectives for traffic signal system operations may be examined and defined collaboratively and the quality of corridor/system performance may be evaluated and presented effectively. A wealth of information on the subject is available at the following Transportation Research Board (TRB) website: Project Description The purpose of the project is to identify the performance measures for traffic signal operations best suited for the TSSIP stakeholders through a pilot implementation. The project has three parts: a study in FY08, followed by design in FY09, and deployment in FY10. DRCOG will be the lead for this project and will be responsible for processing the data and presenting results. 34