CEN39 Coordinated Traffic Management Amsterdam v10

EasyWay

Evaluation Expert Group Document

Coordinated Traffic Management on the A10 Amsterdam Ring Road

Final Version

Issue: 1st

edition

Date: January 28th

, 2013

Issued by: Rijkswaterstaat (NL)

Authors:

Feiko van der Veen, Royal HaskoningDHV

Henk Taale, Rijkswaterstaat

Coordinated Traffic Management on the A10 Amsterdam Ring Road - 2 - January 28th

, 2013

PREFACE

Late 2012 the ex-post evaluation study took place of traffic management scenarios in the Amsterdam

region, comprising a series of coordinated traffic management measures on the A10 Ring Road (E35) and

on the main arterials of Amsterdam. This evaluation document describes the results of this evaluation

study.

The coordinated traffic measures were a continuation of an earlier project within the ‘Fileproof’ Programme,

which was launched by the Dutch Ministry of Transport and Water Management in 2007, executed in 2008-

2009 and evaluated in 2010. The evaluation study of that earlier project, called ‘Improving traffic flow A10’

(in Dutch: ‘Verbeteren Doorstroming A10’, in short: VDA10), was published as an EasyWay evaluation

document in October 2011 (“Evaluation of Ramp Metering on the A10 Amsterdam Ring road”, CEN8).

To further improve traffic throughput, traffic management scenarios have been developed since 2010 in

order to be in command of the different traffic measures in a coordinated way. This implies the execution of

a specific combination of correlated traffic management measures under particular traffic circumstances.

The set of scenarios is additional to the existing traffic management measures such as (locally actuated)

ramp metering at all interchanges of the Amsterdam arterials with the A10 Ring Road, coordination of

these ramp metering stations with adjacent traffic signals, and a large number of urban and motorway

Variable Message Signs (VMS).

The coordinated traffic management project was instigated by the joint road operators Rijkswaterstaat,

Municipality of Amsterdam, province of North-Holland and the city region Amsterdam. The trial with the

new developed traffic management scenarios was started mid 2011 and they were put in operation since

October 2011. The before and after periods for the evaluation of the scenarios took place between

September and December 2011. The data analysis and reports were finalised in December 2012.

This document describes the results of the ex-post evaluation study, based on the analysis of the effects

on traffic throughput and a road user survey.


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TABLE OF CONTENTS

REPORT TEMPLATE .................................................................................... 5

1. Key Evaluation Results ........................................................................ 6

1.1. Impact on Traffic Flow 6

1.2. Impact on Safety 6

1.3. Impact on Environment 6

1.4. Other Key Results 7

2. Description of the Problem .................................................................. 8

2.1. Site 8

2.2. Issues Addressed 8

3. Description of the ITS Project ............................................................ 10

3.1. Service Area 10

3.2. Key Words 10

3.3. Objectives 11

3.4. Systems and Technologies Applied 11

3.5. Costs 13

3.6. Status of the Project 14

4. Evaluation Planned ............................................................................. 15

4.1. Timing and Type of Evaluation 15

4.2. Objectives for the Evaluation 15

4.3. Research Questions 15


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4.4. Study Area for the Evaluation 16

4.5. Expected Impacts 16

4.6. Used Methods 16

5. The Impact of the Project – Results .................................................. 19

5.1. Technical Performance 19

5.2. Results 19

5.2.1. Results at network level .................................................................................................................... 19

5.2.2. Results at sub-network level ............................................................................................................. 21

5.2.3. Results at road section level ............................................................................................................. 23

5.2.4. Results of road user survey .............................................................................................................. 23

5.2.5. Overall conclusions and recommendations ...................................................................................... 24

5.3. Reliability of Results 25

5.4. Research Questions Answered 25

5.5. Overall Assessment 25

5.5.1. Safety ................................................................................................................................................ 25

5.5.2. Efficiency .......................................................................................................................................... 25

5.5.3. Environment ...................................................................................................................................... 25

6. European Dimension: Transferability of the Results ....................... 26

Annex 1: The RWS tool MoniGraph .......................................................... 27


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REPORT TEMPLATE

Project Name: Coordinated Traffic Management on the A10 Amsterdam Ring Road

Project Code: CEN39

Area Code: CS223

EasyWay Region: CENTRICO


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1. Key Evaluation Results

This section presents a brief summary of the key results, specifically related to the EasyWay objectives.

The detailed results can be found in the next chapters.

Brief project description

A large set of traffic management scenarios was developed in 2010 for the Amsterdam region in order to be

in command of the different traffic measures in a coordinated way. These scenarios comprise the execution

of a specific combination of correlated traffic management measures under particular traffic circumstances.

The range of traffic management measures involved include among others (locally actuated) ramp metering

at all interchanges of the Amsterdam arterials with the A10 Ring Road, coordination of these ramp metering

stations with adjacent traffic signals, and a large number of urban and motorway Variable Message Signs

(VMS).

While the local actuation was based on traffic measures for reducing local problems, the scenario approach

is based on the combined and coordinated functioning of sets of traffic management measures for specific

conditions on road stretches, in order to reduce the situation for a complete section of the road network.

The objective of the ex-post evaluation study was to determine the added value of the (coordinated) scenario

approach compared to the local actuation of traffic management measures.

1.1. Impact on Traffic Flow

The main conclusions of the ex-post evaluation were, that the use of the developed traffic management

scenarios:

� Improved the overall traffic performance (vehicle kilometres driven) on the A10 with 2.0% to 2.5%, both

during morning and evening peak,

� Reduced the vehicle hours lost on the A10 with 7.9% in the evening peak, but showed an increase of the

delay with 3.7% in the morning peak. In total there was a reduction of 3.6% during the peak periods.

� Reduced the Congestion Rate1

by 1-3% during the morning peak and 7-9% during the evening peak.

Overall, the effects in the evening peak were more substantial as this was the busiest period of day with the

highest potential of reaching effects.

Travel times on motorways and main arterials of Amsterdam varied considerably: both increases and

decreases were identified for travel time and variation in travel time, compared to the before situation.

1.2. Impact on Safety

Not evaluated.

1.3. Impact on Environment

Not evaluated.

1

Congestion rate (in Dutch: filezwaarte) is the product of length and duration for a specific traffic queue, expressed in kilometre minutes. For example: a congestion rate of 15 kilometre minutes could be both a queue of 15 kilometres during 1 minute as a queue of 3 kilometres during 5 minutes.


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1.4. Other Key Results

The results of the questionnaire among road users shows that the road users experience similar effects as in

the evaluation study based on traffic data: better traffic performance on the A10 motorway and unchanged

traffic performance on the urban road network of Amsterdam.

A major key result of the evaluation study is that (uniformed and centralised) registration of almost all actions

of traffic operators, changes of the statuses in the scenario software and of the roadside equipment is vital

for a thorough evaluation. Due to incomplete registration and logging, several important analyses could not

be made.


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2. Description of the Problem

2.1. Site

The Amsterdam area still suffers from congestion on almost every working day, especially during afternoon

peak hours. Road users who use the A10 Ring Road to enter or to leave the city of Amsterdam, or the road

users who pass the Amsterdam area, are confronted with congestion on motorways that connect to the A10

as well as the Ring Road itself (see figure 2.1).

Figure 2.1 The study area of the project

2.2. Issues Addressed

Dutch transport and traffic policy emphasises a better use of the existing infrastructure, as building new

roads is too expensive and takes too much time due to procedures related to spatial and environmental

conditions and pricing is politically not an option. In order to make better use of the infrastructure, the joint

road managers in the Amsterdam region developed in 2005 plans for regional cooperation in the field of

traffic management. As a result, a large number of VMS’s and ramp metering systems were installed in the

recent years. The first elaboration started under the ‘FileProof’ traffic management programme (2006-2009)

and was evaluated in 2010. It was called the project ‘Improving traffic flow A10’ (in Dutch: Verbeteren

Doorstroming A10). The evaluation report is available as “Evaluation of Ramp Metering on the A10

Amsterdam Ring Road” (CEN8, October 10th, 2011).

The extension of this programme included the development of traffic management scenarios, which were

evaluated in 2012 and for which the evaluation is described in this document. A new programme, called

‘Operational Pilot Amsterdam’ (in Dutch: Praktijkproef Amsterdam), starts in 2013 and involves the advanced


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coordination of traffic lights on main arterials including the ramp metering systems on the A10 Ring Road.

Within this programme also a competition will be held to stimulate the development of advanced in-car

information and navigation services for the study area by private companies.


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3. Description of the ITS Project

3.1. Service Area

The EasyWay Service areas are:

� Traveller Information Services,

� Traffic Management Services,

� Freight and Logistics Services,

� ICT Infrastructure.

In the project involved, Coordinated Traffic Management on the A10 Amsterdam Ring Road, traffic

management services were developed and implemented.

In order to evaluate the effects of these services, traffic monitoring was used to collect and analyse traffic

data and driver behaviour (driver opinions) was investigated through questionnaires.

3.2. Key Words

The following key words (highlighted) describe the nature of the project and the applications used.

Traveller

Information Services

Traffic Management

Services

Freight and

Logistics Services

ICT Infrastructure

Pre-trip Traveller

Information

Variable Speed Limits Freight Management Data Management

and Exchange

On-trip Traveller

Information

Speed Control using

ANPR

Vehicle Safety

Systems

Traffic Management

Plans

Variable Message

Signs

Use of Hard Shoulder Parking Areas DATEX II

Motorway Advisory

Radio

Automatic Incident

Detection

Hazardous Goods

Monitoring and

Tracking

Traffic Monitoring

Driver Behaviour Use of CCTV Transport Security Control Centres

Comprehension and

Compliance

Ramp Metering

Traffic Management

using Rerouting

Enforcement

Table 3.1 Services involved in the project

Notes for table 3.1:

Coordinated traffic management measures (including rerouting) were proposed to traffic operators in the

traffic management centres, based on current, measured traffic situation. They decided which scenarios

should be put in operation. Each scenario included a set of measures like activation of VMS’s and/or ramp

metering.

For the evaluation study, traffic monitoring data was used and a road user survey was done.


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3.3. Objectives

The main objective of the Coordinated Traffic Management project was: ‘Keep the ring road A10 running’.

The detailed objectives of the project were basically similar to the already mentioned 2006-2010 project

‘Improving traffic flow A10’ (in Dutch: Verbeteren Doorstroming A10):

� Less travel time losses on routes which partly cover the A10:

Occasionally time loss on the ramp is accepted, but there should be time benefits on the motorway

A10, with shorter travel times as a result.

� Better traffic performance A10 and connecting corridors:

Less vehicle loss hours,

Less vehicle kilometres.

� Preconditions for the urban road network:

No increase of urban traffic,

No blockage of intersections,

No side effects for target groups public transport, emergency services and bicyclists,

No decrease of traffic safety.

The EasyWay projects overarching objectives which are expected to be achieved by 2020 are as follows:

� 25% improvement in road safety by 2020,

� 25% decrease in congestion, facilitate travel and mobility of people and goods by 2020,

� 10% reduction in the impact on the environment by 2020.

The Coordinated Traffic Management project aims mainly to contribute to the EasyWay objectives by a

reduction in congestion.

3.4. Systems and Technologies Applied

The set of previously installed and during the project used measures included among others:

� ramp metering stations on all 18 interchanges of the urban road network with the A10 Ring road,

� coordination of these ramp metering stations with urban traffic lights on adjacent intersections,

� 25 VMS’s on the A10 motorway and on main arterials of the Amsterdam road network.

Before situation

The ramp metering systems used to operate locally, e.g. based on the traffic flows and speeds on the

motorway A10 and the traffic flows on the on-ramp. However, the ramp metering systems operated already

in a simple coordinated way with the urban traffic lights on adjacent intersections. Coordination was

implemented with simple rules such as “if a queue at the urban intersection exceeds a predefined length,

then the ramp metering system is switched off”.

The VMS’s could be provided with (predefined) texts and images only by intervention of traffic operators in

the traffic management centres.

After situation

The same roadside equipment was used during the Coordinated Traffic Management project, but unlike the

before situation in a more organised way. A set of traffic management scenarios was developed in 2010 for

the Amsterdam region in order to operate the different traffic measures in a more coordinated way. These

scenarios comprise the execution of a specific combination of correlated traffic management measures

under particular traffic circumstances, in order to relieve the traffic situation for a complete section of the


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road network. Since 2011, the systems and organisational setting were implemented and embedded to

manage the regional traffic in this advanced way.

Traffic management scenarios

The main instruments for this new approach are traffic management scenarios which describe the combined

activation of related traffic management measures like VMS’s, traffic lights and ramp metering. The

combinations of these measures are grouped in three types of ‘building-blocks’: for the A10 Ring Road, for

the arterials city-inbound or city-outbound, and for the City Centre Ring Road (S100). For the entire regional

road network, 22 building blocks have been defined. A combination of building blocks is a scenario.

Starting point for the scenarios was the in 2005 approved view for the North-Holland network (in Dutch:

Netwerkvisie Noord-Holland), including the complete regional road network in the study area. With ‘Keep the

Ring road A10 running’ as main objective.

The four main ‘Services’ (solutions) to accomplish this objective are: affecting route choice, diverting traffic,

limiting inflow, increasing outflow. Through services, quick response to changes in the road network is

possible before small disturbance become major delays.

The following scheme was followed for the scenarios (in order of priority):

1. Limiting on-ramps throughput,

2. Facilitating off-ramps throughput,

3. Rerouting of traffic (for instance anti-clockwise over the ring road instead of clockwise).

Building Block Services Traffic Measures (examples)

A10 (motorway ring

road)

Limiting inflow

Diverting traffic

Ramp metering on the A10

Rerouting by using VMS’s

S100 (city ring road) Limiting inflow

Increasing outflow

Diverting traffic

Traffic lights on the urban road network



Arterial city inbound Increasing outflow

Diverting traffic



Arterial city outbound Limiting inflow

Increasing outflow

Diverting traffic




Table 3.2 Relation between Building Blocks, Services and Measures

Scenario Coordination Module (SCM)

The developed Scenario Coordination Module gives advice, based on traffic monitoring, for bringing

network-wide scenarios into action. During the project, the SCM was running as a stand-alone system on a

number of desks in the Regional Traffic Management Centre North-West Netherlands and in the traffic

management centre of the city of Amsterdam.

The SCM advises to put the relevant building blocks into action when the traffic speed on a section of the

A10 or on an S-road (one of the arterials of the Amsterdam urban road network) drops below a certain

threshold value. The coordinating traffic operator in charge has to decide to approve this advice or not. After

approval, the SCM checks per measure the predefined (priority) conditions for activation. If OK, the measure

will be put into action. If not OK, the SCM continuously checks, as long as the advice is still valid, the

conditions for activation. In this way it is possible that the SCM decides to put this measure later into action

when the conditions for activation are finally met.


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The activation of building blocks is determined and managed per area/section of the total road network. In

general, the services within the building blocks of the A10 prevail over the services within the building blocks

of the arterials and the ones related to the city ring road.

A traffic operator can decide to switch off the entire building block or certain measures within the building

block. This may for instance occur when the safety of a waiting queue at a traffic light comes into play.

The result is that several steps are necessary before the measures of an advice are really put into action.

The delay involved was only several minutes during the project. After activation, the predefined conditions

could lead to untimely switching off a certain measure.

Not all of the steps within the sequence were logged by the SCM. The advice and the approval of the advice

were logged as separate files. However, the check on the conditions and the definite activation were not

logged in the SCM. They were available in the log files of the separate systems. See figure 3.1.

Figure 3.1 Operational processes of Scenario Coordination Module (outline)

Activation of building blocks and measures

Managed by the traffic management centres of Rijkswaterstaat (motorways) and the city Amsterdam (urban

road network), the SCM was operational during the evaluation period on:

� Monday to Friday 7:00 – 10:00 h,

� Monday to Thursday 15:00 – 19:00 h

During the evaluation period practically all building blocks for the A10 Ring Road were activated daily in both

peak periods. The building blocks for the arterials city inbound and outbound and for de city centre ring road

S100 were activated less frequently, despite adjustments of the trigger values of some of these building

blocks during the evaluation period.

After approval of the advised building block, the SCM checked if all conditions for activations were met

before the actual activation took place. The SCM did not log this last step. Thus, approval of a building block

by the traffic operator did not imply or guarantee that the involved traffic measures were practically activated.

This could be checked in the loggings of the different traffic management systems. These loggings revealed

the time stamp or the event of activation, but it was not possible to determine whether the roadside system

was activated by the SCM or locally.

3.5. Costs

The project costs were not available but modest: all roadside systems were already implemented and

available. Only the SCM module and the communication had to be developed and implemented.

Advice for use of

building blocks

Check

conditions

Activation of

measures

Monitoring of road

section status

Statelog

SCM

(minute)

System

loggings

Operatorlog

SCM

(event)

Scenario Coordination Module (SCM)

Monitoring of

conditions

Monitoring of traffic situation

(road section speed)

Approval of

building blocks


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3.6. Status of the Project

At the time of writing (January 2013), the Coordinated Traffic Management project itself is finished. The

installed measures and SCM are still operational and work properly. A new programme, called ‘Operational

Pilot Amsterdam’ (in Dutch: Praktijkproef Amsterdam), will start in 2013 and involves the advanced

coordination of traffic lights on main arterials including the ramp metering stations on the A10 Ring Road.

Within this programme also a competition will be held to stimulate the development of advanced in-car

information and navigation services for the study area by private companies.


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4. Evaluation Planned

4.1. Timing and Type of Evaluation

The evaluation study was carried out ex-post in 2012 and included a period of collecting traffic data and

loggings of the different central systems and road side systems. After that the evaluation continued with the

analysis of traffic related effects and a questionnaire among road users. Both types of evaluation used a

before and after survey.

As stated above, a previous evaluation study was conducted, focussing on the effects of local activation of a

large number of traffic management measures on and around the A10 Ring Road. The relation between the

two separate evaluation studies is shown in figure 4.1.

Figure 4.1 Relation between the previous and current evaluation study

4.2. Objectives for the Evaluation

The overall objective of the ex-post evaluation study was to determine the added value of the (coordinated)

scenario approach compared to the local activation of traffic management measures.

4.3. Research Questions

The main question of the evaluation was:

“what are the effects on the local traffic situation and in the entire study area of using the coordinated

activation of traffic management measures through the developed scenarios, compared to ‘local

activation’ of the same measures?”

The traffic related evaluation had four main subjects to investigate and analyse:

1. The effects of the scenarios on the traffic flows of the A10 Ring Road and on urban road network.

The effects on the following aspects were leading:

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Eva

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Basic situation

Available infrastructure and

dynamic traffic management

Local activation of measures A10

highway and infrastructural

measures

Local activation of measures A10

highway and infrastructural

measures

Coordination of measures A10

highway and Amsterdam

(building blocks)

0 - measurement

(May-June 2008 – Oct-Nov 2008)

1 - measurement

(Dec 2009 - Jan 2010)

1 - measurement

(Sept-Oct 2011)

2 - measurement

(Nov-Dec 2011)


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• travel times,

• vehicle hours lost and congestion rate,

• traffic performance of the road network,

• reliability of travel times,

• traffic safety,

• traffic flows of public transport.

2. Are the preconditions for the urban road network met (no spillback on the urban roads)?

3. The added value of the coordinated scenario approach compared to the local activation of traffic

management measures.

4. The lessons-learned of the employment of scenarios and their evaluation for network wide traffic

management in general and for the upcoming ‘Operational Pilot Amsterdam’ in particular.

Answering of the research questions was covered by both evaluations (traffic related indicators and

questionnaire).

4.4. Study Area for the Evaluation

The study area for the evaluation is indicated in figure 2.1 with the red line. It includes the A10 motorway ring

road, the connecting motorways and the Amsterdam urban road network.

4.5. Expected Impacts

The goal-oriented expectations (expected impacts) were used for the comparison of the coordinated

activation and the local activation of traffic management measures. Prior to deployment, the expected effects

of each building block were described as hypotheses. These effects have been tested by practical

experience: each situation with activated scenarios was compared to the situation without scenarios.

The hypotheses at network level, for instance, were based on the corresponding research questions:

� traffic performance of the road network increases in the after situation,

� vehicle hours lost decrease in the after situation,

� congestion rate decrease in the after situation.

Hypotheses were defined at different levels. All of the tested hypotheses are presented in the results section

of this document (chapter 5).

4.6. Used Methods

Data collection and evaluation methods were quite similar to the evaluation study of the local activation.

The indicators for the project evaluation were obtained directly from the research questions (section 4.3).

Data collection method

For the traffic related evaluation, the following data collection systems and methods were used:

� Loop detector data from the Motorway Traffic Management System (MTM) to monitor speeds and

volumes on the motorways.

� Travel time measurement system, installed on the main arterials of the Amsterdam urban road network.

This system is based on Licence Plate Recognition (LPR) and is in use to monitor and measure the traffic

flow effects on the urban network.

� Loggings of different (roadside) systems.


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� Incident and weather reports.

The road user survey was carried out separate from the traffic related evaluation in a before and after survey

among about 1,000 road users (internet panel) using an on-line questionnaire. The questions related to:

� Daily use of the A10 Ring road during the peak hours,

� Perception of the traffic flow on the A10 and urban roads.

Evaluation method

It is essential for an evaluation to have before and after measurements with comparable days. As the total

study area was complex and extensive, there was always ‘something’ to affect the traffic process. The

scenarios primarily aimed to take care of small disturbances in the road network. Thus, it was not necessary

to filter out days with these smaller events in the before and after periods to get a comparable set of days.

In case of major incidents the disturbances were so considerable that they could not be managed with

‘regular’ scenarios. In such cases the traffic management centre deployed measures that relieved the

incident as much as possible. These days were not useful for the evaluation.

For the selection of comparable days, the following steps were completed:

1. Availability of loop data. A major part of the impact analysis was based on loop detector data of the A10

Ring Road. Days without loop data were deleted. This applied also for days without output of the network

indicators by the data processing and analysis tool MoniGraph2

.

2. Check on incidents. Peak periods with major impact on the available capacity were deleted from the

database. In most cases peak periods with a limited number of lanes on the A10 due to accidents. Major

incidents on motorways leading to the A10 and other incidents on the A10 were marked in the database.

These days were part of the selection when appeared that they did not lead to a deviating traffic situation.

3. Check on whether conditions. A

number of days was deleted when

there was heavy fog. Due to the fog,

the hard shoulder running lanes could

not be opened.

4. Check on general traffic situation.

These tests were done based on the

speed-time interval images of the A10

produced by MoniGraph (see figure

4.2). Deviating days (extensive

congestions or almost no congestion)

were deleted from the database.

5. Activation of building blocks. Days

without activation of building blocks by

the SCM were not used for the

evaluation.

Figure 4.2 Example of a speed-time interval image

6. Check on inflow. Finally, the resulting set of days from the previous steps was checked on comparable

traffic inflow on the four major motorways (A1, A2, A4 and A8) leading to the A10 Ring Road. These

2

MoniGraph is a tool from Rijkswaterstaat (developed and maintained by Henk Taale) to process, analyse and visualise data from loop detectors. MoniGraph was used in the evaluation study for processing of all loop data.

For more details, see annex 1.


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traffic flows in the before and after situations appeared to be quite similar, with only small variations of the

inflow values (between -1.9% and +5.6%).


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5. The Impact of the Project – Results

5.1. Technical Performance

The majority of VMS’s and ramp metering systems, including their coordination with adjacent traffic signals,

performed quite well during the evaluation periods. However, at some on-ramps the installation did not

operate adequately: in situations where one might expect (according to traffic data) that the ramp metering

stations would be activated, they were not. Besides limiting trigger values within the SCM, the (local)

configuration of the ramp metering stations could also be the disturbing factor.

5.2. Results

5.2.1. RESULTS AT NETWORK LEVEL

The results at network level concern only the A10 Ring Road, both for the inner ring (clockwise) and outer

ring (anti-clockwise) and for morning and evening peak. Indicators such as congestion rate and vehicle

hours lost on the rest of the road network could not be measured in a proper way, due to unavailability

and/or not applicable to the entire urban road network.

Traffic performance

Traffic performance is the number of vehicle kilometres driven by all vehicles during a certain (peak) period.

The traffic performance was calculated with the MoniGraph tool.

In the morning and evening peak traffic performance had increased by 2.3%-2.5% (see table 5.1). This

indicates a higher traffic throughput on the A10 Ring Road in the after situation. The national increase was

on average 0.5% per quarter of a year. The increase of 2.3%-2.5% within one quarter of a year (see figure

5.1) can therefore be seen as a better throughput due to the activation of scenarios.

Before After Effect

Morning peak Inner ring 508.824 528.769 + 3.9%

Outer ring 417.903 421.134 + 0.8%

Total 926.726 949.903 + 2.5%

Evening peak Inner ring 419.299 436.059 + 2.3%

Outer ring 536.734 541.724 + 2.1%

Total 956.033 977.783 + 2.3%

Both peaks Total 1.882.759 1.927.686 +2.4%

Table 5.1 Traffic performance for the entire A10 Ring Road (in vehicle kilometres)

The average speed on the A10 Ring Road was almost the same in the before and after situation (see table

5.2). In the evening peak, with average speeds usually lower than during the morning peak, the average

speed increased by more than 2%.


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Before After Effect

Morning peak Inner ring 77 76 - 0.6%

Outer ring 81 81 - 0.8%

Evening peak Inner ring 68 70 + 2.3%

Outer ring 69 71 + 2.1%

Table 5.2 Average speed on the entire A10 Ring Road (in km/h)

Vehicle hours lost

Vehicle hours lost are defined as the difference between the actual total travel time (of all vehicles) and the

total travel time under ‘free flow’ conditions. The determined free flow speed was 100 km/h for the entire A10

Ring Road. Vehicle hours lost were calculated using the MoniGraph tool.

During the evening peak, the combination of an increase in traffic performance (table 4.1) in combination

with an increase of average speed (table 5.2) lead to a decrease of vehicle hours lost of almost 8%, primarily

on the outer ring (table 5.3). In the morning peak, the limited increase of the traffic performance lead,

together with a slightly lower speed, to a modest increase of vehicle hours lost of 3.7%. For both peaks the

improvement is 3.6% less delay.

The numbers of vehicle hours lost in the evening peak were substantially higher than in the morning peak,

especially on the outer ring. This is the result of a higher traffic volume during the evening peak with a lower

speed (lower speeds give more weight to the vehicle hours lost).

Before After Effect

Morning peak Inner ring 1.976 2.047 + 3.5%

Outer ring 1.073 1.114 + 3.9%

Total 3.049 3.161 + 3.7%

Evening peak Inner ring 2.172 2.114 - 1.3%

Outer ring 2.958 2.580 -12.8%

Total 5.129 4.724 - 7.9%

Both peaks Total 8.178 7.885 -3.6%

Table 5.3 Vehicle hours lost for the entire A10 Ring Road (in hours)

The national trend showed a decrease of vehicle hours lost of 5.0% to 7.5% in the last quarters of 2011. The

average decrease on the A10 Ring Road was therefore slightly less than the national trend. Of course in the

national trend also the Amsterdam network is included.

Congestion rate

Congestion Rate (in Dutch: Filezwaarte) is the amount of minutes and length for traffic queue with speeds

lower than 50 km/h, expressed in kilometres.minutes (km.min). For example: a congestion rate of 15 km.min

could be both a queue of 15 kilometres during 1 minute as a queue of 3 kilometres during 5 minutes.

Under all circumstances, the congestion rate decreased on the A10 Ring Road (table 5.4), especially during

the evening peak. The congestion rate in the morning peak decreased while the vehicle hours lost

increased. The reason for this had to do with the number of congestion situations: situations with average

speeds of 50-100 km/h increased the number of vehicle hours lost, but did not count up in the congestion

rate. The number of km.min with low speeds (< 50 km/h) decreased therefore, while the number of km.min

with a speed of 50-100 km/h increased. As a result, the number of congestion situations decreased in the

morning peak, but the average speeds dropped slightly (table 5.2).


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Before After Effect

Morning peak Inner ring 743 733 - 1.3%

Outer ring 450 435 - 3.4%

Total 1.193 1.168 -2.1%

Evening peak Inner ring 1011 943 - 6.7%

Outer ring 1018 926 - 9.0%

Total 2.029 1.869 -7.9%

Both peaks Total 3.222 3.037 -5.7%

Table 5.4 Congestion rate for the entire A10 Ring Road (in kilometres.minutes)

The decrease of the congestion rate was in line with the national trend in the same period (7-9% decrease

including 5-6% decrease due to extra lanes). However, the A10 Ring Road did not open extra lanes in the

period considered. This indicates that the traffic management scenarios are partially responsible for the

decrease of the congestion rate.

Conclusions at network level

Hypothesis: traffic performance of the road network increases in the after situation.

� Yes, 2.5% higher in the morning peak compared to the before situation and 2.3% in the evening peak.

Both results were higher than the national trend which showed an increase of 0.5%.

Hypothesis: vehicle hours lost decrease in the after situation.

� Yes and no. Vehicle hours lost decreased in the evening peak during the after situation with almost 7.9%

while it increased in the morning peak by 3.7%. The average speed on the A10 Ring Road did not

change in the morning peak. It increase by more than 2% during the evening peak.

Hypothesis: congestion rate decrease in the after situation.

� Yes, the congestion rate decreased, from 1% in the morning peak on the inner ring and 9% in the

evening peak on the outer ring.

5.2.2. RESULTS AT SUB-NETWORK LEVEL

Traffic performance, vehicle hours lost and congestion rate

The different indicators traffic performance, vehicle hours lost and congestion rate were determined for the

A10 sub-networks North, East, South and West (see figure 5.1). The analysis of these indicators per sub-

network revealed that the evening peak caused most of the delays, especially on the sub-networks South

and West, for which the level of vehicle hours lost was the highest. Similar to the results on network level,

the vehicle hours lost on the outer ring decreased substantially in the after situation compared with the

before situation.

Speed and traffic volume

For the separate sub-networks of the A10, both speed and ‘performance’ of these parts were calculated. The

average traffic volumes of the first and last counting station determined the ‘performance’ of a road section.

The results per sub-network showed considerable differences in speed, but only on sub-network East: the

average speed in the after situation was significantly lower for both morning and evening peak and both on

the inner and the outer ring. For the other sub-networks there was hardly any difference in speed during the

morning peak. The speed on the A10-South increased in the evening peak, but not significantly. However,

this increase had more effect on the vehicle hours lost due to the higher traffic volumes on sub-network

South.


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The differences in ‘performance’ (traffic volumes) between before and after measurements were limited. The

overall tendency is positive: higher traffic volumes during the after situation, similar to the results at network

level.

Figure 5.1 The sub-networks of the A10 Ring road

Congestion development

One of the objectives of the coordinated activation was trying to prevent or decrease congestion. The

activation of the traffic management scenarios appeared not to be able to prevent congestion. The

development of the traffic speed per sub-network was investigated in order to check whether coordinated

activation was able to diminish the development of congestion.

The results showed no clear postponement of the start of congestion in the after period. Moreover, in the

morning peak on the inner ring a decrease of speed occurred even a bit earlier than in the before

measurement. On most of the sub-networks, the development of congestion was almost the same in before

and after situation.

Conclusions at sub-network level

Hypothesis: a higher speed on the sub-networks in the after measurements

� No, the average speed on several sub-networks was not significantly higher than in the before

measurement. On sub-network East it was even significantly lower for both the inner as outer ring and

both in the morning and evening peak. The rest of the sub-network did not show any difference in

average speed.

Hypothesis: higher traffic volumes on sub-networks for the after measurements


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� No, significantly higher traffic volumes were not identified on the different sub-networks in the after

measurements; all differences were quite limited. However, the overall tendency was positive.

Congestion development (no hypothesis)

� The development of the actual speeds during the peaks is an important indicator for the performance on

sub-network level. The results showed no clear evidence that congestion could be prevented with

coordinated activation.

5.2.3. RESULTS AT ROAD SECTION LEVEL

The results on road section level applied both to the motorway network and the rest of the road network.

MoniGraph was used to determine travel times on the motorways, the travel time monitoring system MoCo

of the Amsterdam municipality was used for travel times on the corridors of the urban road network.

Travel times on specific routes

For the motorway network 8 routes were defined. The travel time for the entire A10 Ring Road (inner and

outer ring) was calculated as well. The results showed that travel times on the A10 Ring Road in the morning

peak were basically similar to the before situation. Clear differences appeared in the evening peak. The

increase of travel times on specific routes was the consequence of rerouting via these routes through the

scenarios. Some routes had a longer travel time. Travel times on the different arterials of the urban road

network varied as well. The vast increase of travel time on a specific arterial was caused by road works with

particular traffic light settings.

Travel time reliability

Similar to the results for the absolute travel times on the motorway are the results for the variation of travel

times. In general, the variation of travel times in the morning peak is small. Most of the routes had an even

smaller variation of travel times in the after situation. However, the evening peak showed an increase of the

average variation in travel time, from 4-41% in the after situation compared to 2-14% in the before situation.

No direct explanation was found for this phenomenon.

Conclusions at road section level

Hypothesis: lower travel times on the pre-defined routes

� No, travel times during the morning peak changed only in a limited way. Travel times even increased on

several routes in the evening peak.

Hypothesis: smaller variations in travel times

� No, on the contrary. The variation during the evening peak increased even more.

5.2.4. RESULTS OF ROAD USER SURVEY

Important questions in the road user survey were the use of the A10 Ring Road and the experience of the

throughput of the A10 and the arterials.

The after measurement of the survey took place between end of November and early December 2011. The

results were compared with the result of the first survey (summer 2008) and of the before measurement in

May 2010. Note: the reference period for the before period for the road user survey (May 2010) is quite

different than the before period of the traffic related evaluation (September-October 2011). In one year’s

time, the (national) congestion rate decreased with 24%.


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The daily use of the A10 Ring road by the respondents changed from 17% in the before situation of 2010 to

14% in the after situation, while the traffic performance increased with 2.3%. Part of the explanation could be

found in the composition of the respondents group: one-third of them participated in the first survey. In the

meantime they used the A10 Ring Road less because of changed employment conditions.

The respondents were quite positive about the improved traffic throughput, both in the morning and the

evening peak. The respondents experienced less congestion in both peak periods, in line with the results of

the traffic related evaluation.

The experience with the throughput on the urban road network did not seem to be changed: two-third of the

respondents did report any difference. Travel time measurements on the arterials showed quite some

variation (both increase and decrease) but the margins were limited to a change of 5 to 40 seconds,

apparently not a substantial change according to the respondents.

5.2.5. OVERALL CONCLUSIONS AND RECOMMENDATIONS

Overall conclusions

The overall effects on network level were positive: the traffic performance increased on the A10 Ring Road,

the vehicle hours lost decreased and the congestion rate decreased as well. The effects in the evening

period were higher than in the morning period. Not surprisingly as the evening peak is busier with most

disturbances. In the morning peak travel speeds are normally higher (not below 75 km/h), which leads

evidentley leads tot smaller gains.

Despite some (smaller) negative effects on sub-network level and road section level, the evaluation showed

that coordinated activation of traffic management measures has an added value over local operation.

Especially on the busiest moments and locations: the outer ring A10-South during the evening peak.

Recommendations

The effects could be even higher if the operation would be optimised. Improvement seems to be possible on

two aspects: the operation by the SCM and the development process.

The following recommendations apply:

� Expansion of the operational period of the SMC. Following a quick scan of the SCM loggings, different

network sections ‘asked’ for actuation of building blocks on a regularly basis beyond the peak periods.

� Optimisation of the trigger values for the urban road network. The building blocks for the urban road

network were activated in a very limited way. Further adjustment of these values could improve the

added value of the scenario approach.

� Optimisation of the ramp metering configuration. Analysis of the ramp metering loggings learned that

activation of ramp metering was necessary in more situations than actually performed. Ramp metering

stations were not activated or simply switched off due to limited threshold values for the urban network.

Extension of the threshold values or of the physical space near interchanges could improve this situation.

� Process related improvements. The complete optimisation cycle (plan-do-check-act) was missing.

Through constant monitoring of the scenarios, goal-oriented adjustments would have been possible in

order to optimise the total process. Currently the SCM loggings are in the process of being improved in

order to be able to evaluate and improve scenarios a short time after activation.

� Improve the monitoring through loggings. As stated above, several loggings were missing for thorough

evaluation purposes. The logging of the following items could improve the total process: trigger values,

approval of trigger values, actual actuation of measures (including check on conditions for actuation),

switching off moments of measures (due to exceeding threshold values).


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5.3. Reliability of Results

In order to get reliable answers for the research questions, efforts were done in this ex-post evaluation study

to reduce or even exclude (external) sources of bias, like changes in traffic volume due to economic effects.

More specific:

� The results for the motorway road network are more reliable than for the urban road network. The amount

of available data for the motorways was more than sufficient. For the urban roads only limited data was

available, thus leading to a more qualitative judgement of the effects on these roads.

� As a result of calculations of significance through statistical checks, the determined changes in travel

speeds on the motorways could be regarded as highly reliable for this evaluation study.

Additionally, correlation in the processes from monitoring to advice by the SCM, approval by traffic operators

and the definite activation of road side equipment could not be made completely in detail. As a

consequence, the conclusions above were based on the available data. With better and more detailed

loggings the evaluation study would gain more value with more reliable analysis of effects as a result.

5.4. Research Questions Answered

See section 5.2

5.5. Overall Assessment

Below the main finding of the evaluation are summarised in brief in terms of contribution to the European

objectives.

5.5.1. SAFETY

Based on (partly limited) data available, no hard conclusions could be drawn. However, traffic safety did not

seem to be decreased within the study area.

5.5.2. EFFICIENCY

Travel times and vehicle hours decreased by the traffic management scenarios and traffic performance

increased. This improved the overall accessibility of the Amsterdam region and the city itself in particular.

It facilitated the mobility of people and goods, and contributes at least partly to the 25% objective of

EasyWay.

5.5.3. ENVIRONMENT

Not evaluated and it is difficult to draw conclusions Delay has decreased but kilometres driven increased and

also the speed, leading to different effects.


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6. European Dimension: Transferability of the Results

The following conclusion can be made regarding the applicability of the results of this project to other similar

implementations in the Netherlands and other countries:

� The deployment of traffic management scenarios, using basically allready installed roadside equipment in

the study area, could be profitable for major cities in order to achieve a better throughput of the traffic in

the entire area. This is especially the case at peak hours and in situations where traffic volumes on the

ring road proves to be very high (volume/capacity ratio >0.8).

� Development of traffic management scenarios should be done on a tailor-made basis: all road networks

are different and require specific configurations, trigger values and threshold values.

� Solid traffic monitoring tools and loggings proved to be the vital factor for a constant improvement of the

traffic management processes including traffic scenarios.


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Annex 1: The RWS tool MoniGraph

MoniGraph is a tool to process, analyse and visualise data from the Rijkswaterstaat loop detectors. It was

developed and is still maintained by Henk Taale. In the two figures below, an example is presented for the

visual output of MoniGraph. With this tool it is possible to produce a graphical representation of the traffic

speeds in a certain time period.

In the examples, the traffic situation on the entire A10 Ring road can be observed, from the Coentunnel in

the north of the A10 (at the bottom of the graph) via the outer ring (anti-clockwise) back to the same tunnel.


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The first graph shows a before situation, the second an after situation. Per graph, three typical afternoon

peaks were selected of specific days with low, medium and high traffic volumes. The graphs show the

measured speeds as a function of time and space. All input for these graphs came from the loop detectors

on the A10 motorway.

CEN39 Coordinated Traffic Management Amsterdam v10

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