JUSTIFY

Methodology for Measuring NaviGAtor ITS Performance ITS Georgia Annual Meeting 2010 Presented By: Prasoon Sinha, P.E, PTOE Department Manager, ARCADIS

Deficiencies in current practices Approach to estimating benefits of NaviGAtor/ITS Approach to estimating secondary crashes and ITS impact parameters How can we perform better? Summary Outline Presentation Goals

Background Do not segregate the benefits of ITS and geometric operational/safety improvements Absence of traceability between problems and solutions Use national values of “ITS impact parameters” which may not be applicable to all areas Analysis results do not reflect accurate benefits Do not identify the deficiencies in the existing ITS and roadway infrastructure to answer the question “How can we perform better?” Current Practices

Benefits of ITS/NaviGAtor System Methodology Benefits = Performance Without ITS - Performance WithITS Three main ingredients to the methodology: Traceability between various incident types and applicable countermeasures/solutions Approach to estimation of secondary crashes Approach to estimation of area-specific “Without ITS Conditions” / “ITS Impact Parameters”

Traceability Between Problems and Solutions Trigger Event Queues Severities (Fatalities, Injuries, PDO) Due to Primary Crashes Recurring Congestion Queues Secondary Crashes Severities Queues Delay Emission Throughput Delay Emission Throughput Fatalities Injuries PDO Fatalities Injuries PDO Delay Emission Throughput Tied to and Addressed by ITS Deployments Tied to and Addressed by Operational and Safety Improv. Cost of Severity Value of Time Queuing Eqn. Bad Weather Debris Stalled Vehicle Work Zones Special Events Primary Crashes Bad Weather Debris Stalled Vehicle Work Zones Special Events Primary Crashes Demand > Capacity Demand > Capacity

Benefits of ITS/NaviGAtor System Categorize current crash data by trigger events Estimate queues due to all trigger events (using queuing theory equations) Estimate secondary crashes resulting from all trigger events Estimate severities due to primary crashes Perform travel time comparisons (under “No trigger event” condition) to quantify recurring congestion Form Data Groups & Estimate Secondary Crashes Area of Influence (spatial & temporal coordinate)

Benefits of ITS/NaviGAtor System Data Availability and ITS Impact Parameters Not Available Available Without With NaviGAtor/ITS Operational & Safety Improv. Need to estimate “Without NaviGAtor/ITS” conditions data -> Estimate Impact Parameters Define control corridors Corridors having “Without ITS” and “With ITS” data  I-285 West wall (between I-75 and I-20)  SR 400 between I-285 and Old Milton Pkwy  I-85, South of Camp Creek Pkwy Control group corridors (currently No ITS)  I-20 east of Panola Road

Benefits of ITS/NaviGAtor System ITS Driven Congestion Benefits - All Trigger Events MAX QUEUE LENGTH DELAY FOR DURATION OF INCIDENT Incident Clearance Time QUEUE CLEARANCE TIME DELAY COMPONENTS QUEUE CLEARANCE TIME DELAY DURING CLEARANCE TIME TOTAL DELAY (D T ) D T = D i + D g TOTAL DELAY (D T ) D T = D i + D g V- Average Volume on the freeway C- Freeway Capacity at LOS E r- Capacity Reduction Factor g- Average flow rate during queue clearance time CARS TRUCKS TRANSIT Delay By Travel Mode Delay Savings ($) Time Value of Money ($$$) Fuel Consumption($) Reduced Emission ($) Total Congestion Benefits ($) Congestion Before = Delay D T (Before) + Emission (Before) + Fuel Consumption (Before) Congestion After = Delay D T (After) + Emission (After) + Fuel Consumption (After) Congestion Benefit (CB-ITS)= Congestion Before - Congestion After Congestion Before = Delay D T (Before) + Emission (Before) + Fuel Consumption (Before) Congestion After = Delay D T (After) + Emission (After) + Fuel Consumption (After) Congestion Benefit (CB-ITS)= Congestion Before - Congestion After

Benefits of ITS/NaviGAtor System Benefit of ITS & Proportion of ITS Benefits Benefits ITS Total = Congestion Benefit (CB-ITS) + Safety Benefit (SB-ITS) Benefits Ops Total = Congestion Benefit (CB-Ops)+ Safety Benefit (SB-Ops) Benefits Total = Congestion Benefit (CB-ITS) + Congestion Benefit (CB-Ops)+ Safety Benefit (SB-ITS) + Safety Benefit (SB-Ops) Benefits Total = Congestion Benefit (CB-ITS) + Congestion Benefit (CB-Ops)+ Safety Benefit (SB-ITS) + Safety Benefit (SB-Ops)

Justifications for Future ITS Deployments How Can We Perform Better? Categorize incident data by Trigger Events (GIS database, thematic maps) Conduct Hot-Spot Analysis Query to identify highest secondary crash locations (ITS) or high primary crashes (operational or safety improvements) Identify existing NaviGAtor coverage at Hot-Spot locations Identify the gaps in deployment and match it with problem type Fill the gaps in deployment Deploy ITS that can address primary crashes & recurring congestion

A robust methodology that: Resides on a GIS platform which ties perfectly into the NaviGAtor dashboard Provides B/C ratios by corridors and by overall system – Provides equations for estimation of secondary crashes and calculations of ITS benefits and costs – Provides approach to estimating region specific ITS impacts Categorizes the share of non-recurring congestion by incident type Provides ratio of ITS Benefits to Overall Benefits Identifies existing system deficiencies, recommends potential countermeasures and expected benefits Provides Funding Justification for ITS In Summary…..

Contact Information: Prasoon Sinha, PE, PTOE ARCADIS (770) Thank You!