TRAFFIC SIGNAL TRAFFIC SIGNAL MANAGEMENTMANAGEMENT

PURPOSEPURPOSE

Purpose: Foster understanding through development of educational outreach materials Illustrate benefits and basic techniques Share information on new technologies Highlight need for multi-municipal

cooperation Target Audience:

Municipal Officials, Planning Commission Members, Municipal Staff Members

WHAT IS TRAFFIC SIGNAL WHAT IS TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

The use of current tools, techniques and equipment to manage streets and signal systems more efficiently and in a cost-effective manner in order to improve safety, economic vitality and quality of life.

The #1 investment we can make for immediate positive impact.

Cost-effective way to improve traffic flow.

Maximizes the benefits of the existing infrastructure.

WHAT IS TRAFFIC SIGNAL WHAT IS TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

2/3 of all miles driven are on signalized roads

Over 300,000 signals in U.S. 75% of the signals could easily be upgraded Congestion affects everyone’s mobility Adding capacity

Expensive Long implementation timeframe Potentially controversial Environmental and social impacts

WHY TRAFFIC SIGNAL WHY TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

Less Congestion

Improved Fuel Consumption

Vehicle Emissions Reduced

Improved Air Quality

WHY TRAFFIC SIGNAL WHY TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

Properly designed, operated and maintained traffic signal systems yield significant benefits:

Cost effective: cost ratios of 40:1 Low-cost alternative to physical

reconstruction

Arterial management Saves time for commercial vehicles,

emergency vehicles, buses and the public

Reduces aggressive driving behavior, red light running

WHY TRAFFIC SIGNAL WHY TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

Postpone or eliminate need for additional capacity

Safety – reduce accidents by providing smoother traffic flow with fewer stops

Maintenance and training streamlined

Improved pedestrian flow, side-street movements

Municipal cost and energy savings

WHY TRAFFIC SIGNAL WHY TRAFFIC SIGNAL MANAGEMENT?MANAGEMENT?

HOW CAN BENEFITS HOW CAN BENEFITS BE ACHIEVED?BE ACHIEVED?

Standardization of equipment Remove unwarranted signals Install and maintain equipment

properly Traffic signal retiming Implement additional signal plans based

on time of day/day of week Turn lanes and minor intersection

improvements

STRATEGIESSTRATEGIES

STRATEGIESSTRATEGIES

Traffic Signal Equipment Enhancements: Isolated or independent signals

Arterial Interconnected Signals Time based coordination

Closed Loop Systems

Centrally Interconnected & Controlled Systems

Personal computer (PC) based

Traffic Operations Centers

Detection & Actuation Detection & Actuation StrategiesStrategies

Fixed Time Operations High traffic and pedestrian volume areas, Not flexible for changing traffic patterns Central Business Districts hours

Semi Actuated Operations Applicable to corridors No detectors or actuation on main streets

Fully Actuated Operations Most flexible Best for isolated signals

GOALSGOALS

Centralized coordination of signals Coordinate signal operations over

jurisdictional boundaries Integrate traffic flow over larger areas Corridor Administrator to set up and

implement Municipal Training Dedicated funding stream Administrative hierarchy

MULTI - MUNICIPAL COOPERATIONMULTI - MUNICIPAL COOPERATION

Procurement Methods: Department of General Services (DGS)

COSTAR program Purchase equipment as public procurement unit =

economies of scale lower costs

Cost Sharing concept allows municipalities with smaller budgets to benefit too

MULTI - MUNICIPAL COOPERATIONMULTI - MUNICIPAL COOPERATION

Equipment better maintained Reduced liability Maintenance streamlined with standardization

Funding for larger projects Municipality retains basic timing parameters Costly reconstruction postponed by utilizing

existing facilities more efficiently Repairs made more quickly

Traffic Signal System Traffic Signal System Improvement ProgramImprovement Program

Traffic Signal Retiming

Signal Maintenance Strategies

Utilize New Technologies

Traffic Signal SystemTraffic Signal System Improvement Program Improvement Program

Traffic Signal Retiming: Interconnect signals

Wireless technology Hardwire interconnectivity

Coordinate signal controllers Reassign green time

General cost range $760 - $2,700 per intersection

20-25 hours per intersection

Traffic Signal SystemTraffic Signal System Improvement Program Improvement Program

Signal Maintenance Strategies: Preventive Maintenance Remedial Maintenance Staffing Rules-of Thumb

One traffic engineer per 75-100 signals One signal technician per 40-50 signals

Consultants often supplement staff Eligible for Federal Aid Funds

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Utilize new technologies: ACS Lite (Adaptive Control Software) allows older

software to communicate Interconnecting signals Spread Spectrum (wireless) Actuating Signals Develop emergency priority corridors Use of LED signal lamps

Traffic Signal SystemTraffic Signal System Improvement Program Improvement Program

SAVINGS Signal maintenance costs Energy costs

LED SIGNAL LAMPSLED SIGNAL LAMPS

Avg. intersection:10 vehicular signals/

8 pedestrian

Incandescent bulbs

LED Signals

Per vehicular signal 135-150 watts 8-10 watts

Per pedestrian signal 70 watts 8 watts

Per intersection 2060 watts

$175/month

164 watts/less

$23/month

Annual cost / intersection $2,100 $276

Average savings of $1,824 monthly/ $40,128 annually per intersection

TESTIMONIALSTESTIMONIALS

A statewide traffic signal retiming program in California found the following benefits:

7% reduction in travel time 14% reduction in delay 9% saving in fuel Benefit/cost ratio 58:1

TESTIMONIALSTESTIMONIALS

A new signal system and improved signal timing conducted in Abilene, Texas (a mid-sized urban area) achieved:

13% reduction in travel time 37% reduction in delay 6% fuel saving

TESTIMONIALSTESTIMONIALS

An advanced traffic control system in Oakland County, Michigan (a large suburban area) achieved:

30% reduction in delay 19% increase in peak hour speeds 6% reduction in accidents 33% reduction in stops

Route 51 CorridorRoute 51 Corridor

SYNCHRO/SIMTRAFFIC MODEL – SYNCHRO/SIMTRAFFIC MODEL – MOE’sMOE’s

Total Network Performance PM Calibrated PM Optimized

Total Delay (hours) 49.1 44.4

Delay/Vehicle (seconds) 117 109

Total Stops 3498 3214

Travel Distance (miles) 2691.1 2514.6

Travel Time (hours) 123.3 113.2

Average Speed (mph) 22 22

Fuel Used (gallons) 198.3 179.8

Fuel Efficiency (mpg) 13.6 14

HC Emission (grams) 514 481

CO Emission (grams) 19643 18991

NOx Emissions (grams) 1603 1491

Vehicles Entered 1744 1686

Vehicles Exited 1276 1246

Hourly Exit Rate 7656 7476

Denied Entry Before 1 3

Denied Entry After 2 0

TRAFFIC SIGNAL OPERATIONS SELF TRAFFIC SIGNAL OPERATIONS SELF ASSESSMENT TOOLASSESSMENT TOOL

Help agencies understand opportunitiesfor improving their own policies andpractices

Designed for any agency responsible for operation and maintenance of traffic signals

One hour to complete No data collection required Results used anonymously in the 2007 National

Traffic Signal Report Card To use tool:

http://www.zoomerang.com/recipient/survey-intro.zgi?p=WEB225U6FTB7YM

ADDITIONAL RESOURCES:ADDITIONAL RESOURCES:

FHWA Operations web site: http://ops.fhwa.dot.gov

Traffic Signal Operation Self Assessment: www.ite.org/selfassessment

MARC – Operation “Green Light”: www.marc.org/transportation/ogl/

ACS Lite Software: raj.ghaman@fhwa.dot.gov

PennDOT: http://www.paits.org/tsop/index.htm

SPC: http://www.spcregion.org/trans.shtml