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DANISH ROAD INSTITUTE

TECHNICAL NOTE 79 - 2010

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AUTHOR:

Emine Celik Christensen

DATED: December 2010 LAYOUT:

Svenning Olm, Berit Jensen PHOTO: Road Directorate Eagle Luftfoto ISBN ELECTRONIC: 978-87-92094-74-2 COPYRIGHT: Road Directorate, 2010 PUBLISHED BY:

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PREFACE 5 SUMMARY 7

1. INTRODUCTION 11

1.1 Background 11

1.2 Earlier research 18

1.3 Objective of the investigation 19

2. COMMUNICATION PROCES 20

3. NOISE ABATEMENT 23

3.1 Noise mapping 23

3.2 Noise barrier 24

3.3 Noise reducing pavements 35

3.4 Sound insulation of building facade 35

4. MATERIAL AND METHODS 37

4.1 Study area and study sample 37

4.2 Questionnaire 45

4.2.1 Structure and content 45

4.2.2 Pilot testing 47

4.2.3 Distribution 47

4.2.4 Data processing 48

4.3 Calculations of noise exposure 48

5. RESULTS 52

5.1 Noise levels in the study areas 52

5.1.1 Area A 53 5.1.2 Area B 56 5.1.3 Area C 58 5.1.4 Area D 60 5.1.5 Area E 62 5.1.6 Area F 64

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5.2.4 Sensitivity to noise (Q41) 73 5.2.5 Number of people permanently living in the residence (Q43) 74

5.2.6 Children in the residence (Q39) 76

5.2.7 Type of residence (Q18) 77

5.2.8 Ownership of the residence (Q19) 78

5.2.9 Years in present home (Q42) 79

5.2.10 Plans about moving (Q44, Q45) 80

5.2.11 Participation in the pre-questionnaire (Q46) 82

5.3 Annoyance from road traffic (Q1) 84

5.4 Annoyance from road traffic noise (Q2a) 89

5.4.1 inside the house (Q3, Q4, Q5) 90

5.4.2 Outside the house (Q6, Q7) 95

5.5 Noise abatement 98

5.5.1 What should be done to reduce the noise (Q15) 98 5.5.2 What have the respondents done to reduce noise (Q14) 99

5.5.3 Who should pay for noise reductions (Q17) 101

5.5.4 Willingness to pay (Q16) 103

5.6 Communication process 104

5.6.1 Participation in the process / discussions (Q34) 104

5.6.2 Experience with the communication process with Danish Road Directorate and other actors (Q33, Q35, Q36) 105 5.7 Change regarding noise environment (Q8, Q9, Q10, Q11, Q12, Q13) 109

6. CONCLUSION 118

REFERENCES 121 APPENDIX 125

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Due to the increase in traffic, the Danish Parliament decided in January 2001 to widen Motorway 3 which is a city motorway that runs through a heavily populated area around Copenhagen. The construction work started in April 2005 and ended in November 2008.

Great efforts were made to reduce the noise exposure from road traffic for the many thousand neighbours who live a short distance from the motorway in connection with the widening of the 17 km long motorway section from two to three lanes in each direction between Jægersborgvej and Holbækmotorvej. As a part of the project, an investigation on noise annoyance due to road traf-fic noise was carried out by the Danish Road Directorate. The investigation was designed as a pre and post-study which contains the responses from people who live in the residential areas along Motorway 3. Subjective re-sponses were collected by means of two mail questionnaires carried out be-fore the widening in 2003 and a year after the construction work was finalized in 2009.

This report describes the investigation and presents the results obtained. It must be emphasised that data collected by means of a questionnaire survey is the participants’ own perception and report. The responses are from six se-lected housing areas along the motorway.

The criteria for the development of socio-acoustic surveys that have been ap-plied in this survey derive from the work of the International Commission on Biological Effects of Noise - ICBEN [1]. The project was carried out by a group mainly consisting of researchers from the Danish Road Directorate.

The design of the questionnaire survey, including the questionnaire itself, was discussed in 2003 with an expert group with the following members:

 Lene Mikkelsen, Danish Road Directorate

 Hans Bendtsen, Danish Road Directorate / Danish Road Institute  Bent Andersen, Danish Road Directorate / Danish Road Institute  Lars Ellebjerg Larsen, Danish Road Directorate / Danish Road Institute  Niels Gottlieb, Danish Road Directorate

 Hanne Lylov Nielsen, Environmental Protection Agency  Jørgen Horstmann, Environmental Protection Agency

 Torben Poulsen, Acoustic Technology, Denmark Technical University  Marie Louise Bistrup, National Institute of Public Health

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The pre-questionnaire survey has been carried out by the consulting company Atkins Denmark, while the post-questionnaire survey has been carried out six years later by the Danish Road Directorate by the same experts who carried out the pre-questionnaire earlier; at that time Hans Bendtsen, Bent Andersen, Lars Ellebjerg Larsen were employed at Atkins Denmark.

For many years, the noise indicator LAeq,24h has been used in Denmark when assessing noise from road traffic. A new indicator, LDEN, was introduced by the Environmental Protection Agency in 2007. The noise mapping for the M3 pro-ject was performed using the noise indicator LAeq,24h. All the noise levels pre-sented in this report are A-weighted. The unit “dB” is used in this report and it is equal to what is often denoted “dB(A)” or “dBA”.

The noise calculations were carried out by Lars Find Larsen from COWI. The data analyses were carried out with valuable feedback from Hans Bendtsen. The report is written by Emine Celik Christensen with comments from Hans Bendtsen. Proof reading of the final report and translation (Danish-English) of the questionnaire, cover letter and reminder were made by Helen Hasz-Singh. The authors gratefully acknowledge the valuable comments and recommen-dations of the expert group in the design of the questionnaire and contribution to the pilot testing. The authors would also like to thank all respondents for participating and making this study possible.

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Due to the increase in traffic, the Danish Parliament decided to widen Motor-way 3 (M3) from four to six lanes on a 17 km long stretch in January 2001. By 2005, the traffic volume was 90,000 vehicles/day. M3 is an urban motorway that runs through a heavily populated area around Copenhagen. In a belt of 500 metres on both sides of the motorway around 14,000 dwellings are locat-ed meaning that around 30,000 people live along the motorway.

Before the widening of M3, there were 1.5-2.0 metres high noise barriers. As part of the reconstruction project, four meter high noise barriers were built and noise reducing road pavements were laid. A detailed noise map showed that if the previously constructed low noise barriers along the M3 were kept until 2010, there would have been approximately 6,300 dwellings exposed to more than 55 dB of noise from the motorway traffic. However, by 2010, after the M3 was widened to six lanes and new noise barriers were constructed, only ap-proximately 2,200 dwellings were actually exposed to noise higher than 55 dB from the motorway.

As a part of this widening process, an investigation on noise annoyance from road traffic noise has been carried out by Danish Road Directorate before and after the construction. The investigation was designed as a pre and post-study containing responses from the people living along the motorway in six resi-dential areas with some 1,200 dwellings situated at distances from a few me-tres to 500-800 meme-tres from M3. Subjective responses were collected by two mail questionnaires that were sent out during the period of October-November 2003 and November-December 2009 respectively. The response rate was 71% in the pre-study and 65% in the post -study which can be considered quite high for this type of public questionnaires.

Detailed noise calculations in the six selected investigation areas show that M3 is the main source of high noise levels. The noise exposure from other main roads and local roads in the six areas is considerably lower. In the after-situation, no households are exposed to more than 60 dB; while in the pre-situation 5% were exposed to more than 60 dB. In the pre-pre-situation, 45% of the population was exposed to noise levels between 55-60 dB, and this is sig-nificantly reduced to 22% in the post-situation. Around 50% of all dwellings were under 55 dB in the pre-situation and this has increased to around 78% in the post-situation after the widening of the M3.

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 Over 60% have lived in their dwelling for more than ten years.  In the post-study, the respondents have lived longer in their dwelling.  70% of the respondents reports having a normal sensitivity to noise.  In the post-study, there is a tendency towards higher incomes.  Both in the pre and post-study, 10% have plans to move.

 38% of the respondents stated that they participated to the pre-study

On that background it has been decided that the population of respondents in the pre and the post-study are relatively alike and therefore it is reasonable to compare the results from the two studies.

As a start to the questionnaire, the respondents got a general question on noyance from road traffic. It is clear that noise is the dominant source of an-noyance. Before the widening of the M3, 83% of the respondents highlighted noise as a source of annoyance and this reduces to 68% after the construc-tion process. The percentage of respondents who do not experience any an-noyance is increased form 10% to 20%.

When the respondents were asked if the noise had changed during the last two to three years, 27% in the post-study answered that the noise has been reduced, and 44% think it is more or less unchanged. In the post-study 22% think the noise has increased and this is an improvement from the pre-study where 58% stated that the noise had increased during the latest two to three years.

The main result of the two studies is the changes in the generally perceived noise annoyance from road traffic in the whole area including noise from M3 as well as local roads and other main roads. The percentage of very and ex-tremely annoyed respondents decreases from 37% to 16%. The percentage of moderately annoyed is nearly constant with 30% and 27% respectively. Fi-nally, the percentage of slightly or not annoyed increases from 33% to 57% from the pre to the post-study. As a total this is a remarkable reduction of the perceived noise annoyance in the areas studied around M3 for the new situa-tion after the extension of M3.

The questionnaire shows that M3 is the main source noise annoyance. After the widening, the perceived noise from M3 decreases while other major roads and local roads became more obvious.

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has decreased to app. 7% in the post-study.

For all activities related to being outside in the garden, there is a decrease in the reported annoyance in the post-study. The percentage of people who indi-cate annoyance during conversations is reduced from 36% to 20%. The per-centage who indicate annoyance while reading outside decreases from 42% to 29% and finally the percentage annoyed while using the telephone is re-duced form 19% to 12%.

More than 70% of the respondents were not planning to move from their houses and there is no change between the percentages of respondents who is planning to move. Twenty three percent reported that traffic noise was the main reason for having plans to move in the pre-study and this decreased to 14% in the post-study.

The respondents were asked what should be done to reduce the annoyance from road traffic noise. The percentage of respondents who recommend that nothing should be done increased from 13% to 28%, the percentage of re-spondents who recommended to build noise barriers decreased from 61% to 28%, while the percentage of respondents’ suggesting to use noise reducing noise pavements decreased from 61% to 40%.

Response distribution shows that a large majority of the respondents (app. 70%) did nothing themselves to reduce noise annoyance where they live. In-stalling noise reducing windows is the second most common answer (15% to 20%). The increase in the installation of noise reducing windows after the widening of M3 may partly be explained by the Danish Road Directorate’s of-fer to subsidize sound insulation of building façades. A large majority of the respondents (more than 70%) see it as the responsibility of the authorities to reduce noise.

Most of the respondents are not at all eager to pay themselves to reduce noise. But there is a certain willingness to pay from 23% to 24%. There are 23% who in the pre-study do not know whether they would be willing to do so and this decrease to 18% in the post-study.

Thirty percent of the respondents have actively participated in the pro-cess/discussion about the rebuilding of M3, while 40% did not want to do so. Eighteen percent of the respondents claimed they did not get the possibility to participate.

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Both subjective noise annoyance responses and objective noise level calcula-tions showed that there has been a great improvement in the environment along M3 as regards noise. Although the number of daily vehicles passing on M3 has increased significantly compared to six years ago, with the help of combined noise abatement solutions, noise levels have decreased and overall subjective responses on noise annoyance from traffic noise have significantly reduced.

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1.

INTRODUCTION

In modern times, road traffic noise is recognized as a serious environmental problem which raises several aspects in the general public’s awareness with regard to the increasing number of vehicles circulating on urban road network. Road traffic noise is a typical example of conflict between the needs for indi-vidual mobility and the desire for a quieter lifestyle. Noise is known as one of the most frequently reported negative environmental effects of traffic. It has been estimated that about 30% of the population in Denmark is exposed to road traffic noise at levels exceeding 55 dB.

Road traffic is the main source of transport noise in urban areas. To achieve an effective road traffic noise policy requires a combined approach that bal-ances overall road-related sound emission without affecting citizens’ right to mobility.

1.1BACKGROUND

During the 1960’s, due to Denmark’s post-war economic boom, the traffic on M3 which was a smaller road around Copenhagen was growing significantly. In order to relieve some of the traffic congestion from this road, the Danish Parliament decided to construct a new road. The new road is called shortly M3. M3 is situated approximately 15 km west of the centre of Copenhagen in Denmark and runs almost parallel between Ring Road 3 and Ring Road 4 (Figure 1.1 and Figure 1.2)

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Figure 1.1. Map of Copenhagen (left), M3 (“Motorring 3” in Danish) connecting the Danish capital Copenhagen to the rest of Denmark and Europe through six motorways (right).

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The construction of the M3 was decided in 1954 and was started in 1966. Figure 1.3 shows a view from M3 around 1960’s.

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The section between Jægersborg and Jyllingevej was opened in 1968/71. In 1977, a new section connecting it to Holbækmotorvej was built. All the stages, in which the construction of the M3 was completed [2] are shown in Figure 1.4.

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M3 connects the growing suburban areas, the city centre and other motor-ways which connect Denmark with the rest of the Europe [3]. Therefore, a few years after the construction was completed, it became the most important road around Copenhagen.

However, over the last 25 to 30 years, traffic on the M3 has increased consid-erably to the point where long queues occurred during rush hours and vehicle speeds slowed down to 25-30 km per hour. During the 1980’s, there were ap-proximately 35.000 vehicles a day on the M3, during 1990’s this number in-creased to 55.000 and in 2005, there were more then 90.000 vehicles a day on the M3 [4].

Due to the increase of traffic volume, it became necessary to find a new solu-tion. The Danish Road Directorate carried out a detailed investigation aiming to solve the growing problem. On the basis of this investigation, the widening of the existing two-lane motorway to three lanes in each direction for 17 km was considered and chosen as the best solution among the alternatives [3]. An idea sketch of the solution chosen can be seen in Figure 1.5.

Figure 1.5. Idea sketch of the widening of M3 from two to three lanes in each direction.

During the widening process, one of the challenges was to keep the motorway functional throughout the entire four year construction period (Figure 1.6).

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Figure 1.6. Construction work on M3 during the widening

During the construction, 235 properties were partly and 15 properties were ful-ly expropriated. Additionalful-ly, 314 properties were used as temporary working areas for a limited period of time (see Figure 1.7).

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Figure 1.7. Some of the properties were used as temporary working areas for a limited period of time during the widening of M3.

A close communication process was created between Danish Road Direc-torate and inhabitants living along M3 while the construction was on-going, which made it possible for inhabitants to comment on the process to some ex-tent (Chapter 2).

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Figure 1.8. M3 after widening; Denmark’s first architecturally designed motorway [5].

1.2 EARLIER RESEARCH

Annoyance from noise is affected by both individual and noise-source related factors. Individual factors are noise sensitivity, attitude to the noise source, physiological and psychological state, and situational factors such as activities performed or intended to be performed. Noise-source related factors are con-trollability of the noise source, information content and permanence. Hence, the same noise may result in totally different responses and reactions from different people depending on cultural factors [6], attitude to the noise source [7] and [8], noise sensitivity [8], controllability of the source [9], and other situ-ational and individual aspects (see e.g. [10] and [11] for a review).

Predicting a community’s reaction to urban traffic noise is not easily made, based only on simple quantitative measures. To process suitable descriptors for the subjective judgment of noise exposure by means of simple objective measures is not easy to fulfill when individual differences come into play. Several attempts have therefore been made with the goal of correlating sub-jective annoyance and noise exposure [12], [13] and [14]. After reviewing nu-merous surveys, Shultz was able to synthesis a single curve for the relation-ship between community reaction and noise exposure [15].

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When attempting to measure the degree of annoyance caused by traffic noise, the questionnaires and interviews to be answered by the responders and the test volunteers are also important. There are several models for such questionnaires. In the present study, the development of the survey derived from the work of the International Commission on Biological Effects of Noise [1].

1.3OBJECTIVE OF THE INVESTIGATION

There have been few Danish surveys covering the subject of annoyance from traffic noise [16], [17]. The first survey dates back to the early 1970’s; since then, society has changed significantly which might have resulted in a change of the actual noise situation as well as people’s tolerance to noise. In 2002, a large survey covering three urban areas in Odense, Randers and Århus was published [17].

The aims of the present investigation are;

 To find out what is the differences in annoyance levels before and after the widening of M3

 To obtain a better knowledge on how people are annoyed by road traffic noise

 To provide up-to-date knowledge on noise annoyance

 To analyze the noise annoyance in various situations, which people expe-rience during the day.

Therefore it was decided to carry out a questionnaire survey covering the se-lected areas of interest.

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2.

COMMUNICATION PROCES

M3 passes through a number of residential areas in which about 14,000

hous-ing units are located in a range of about 500 metres each side of the road. This means about 30,000 people live close to M3. During the whole process from the earliest to the last phases of the project, communication with the public was taken very seriously and resources have been allocated by the Danish Road Directorate. There has been a full time communication employ-ee working on the project who could be accessed by the neighbours all day. The public received continuous information about the progress of the project via public hearings, neighbour and company forums, information letters and an internet homepage.

The Danish Road Directorate has carried out two public project hearings. Each hearing consisting of a number of informational meetings and debates, where citizens could make remarks and comment on the project (Figure 2.1). An introductory hearing was held during the idea and proposal phase of the project. A final hearing with the results of the plan for the M3 was also held. In addition, a number of informational meetings were held between the two hear-ings.

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Annoyance from traffic noise has often been the most important topic at the meetings. Suggestions and alternative solutions have been discussed during these meetings.

To ensure a high level of communication between the Danish Road Direc-torate and the public, a neighbourhood forum was set up. In the forum there have been about 50 participants such as stakeholders and property owners, which meet two to four times a year to discuss issues and concerns on the M3 project. The forum was also used by the neighbours to influence the design of the noise barrier for the M3, and the type of plants that covers the barriers along each residence etc. These meetings enabled the Danish Road Direc-torate to give information on the progress of the project and to receive rele-vant feedback from local authorities and the public. Similar information meet-ings were also set up for the companies in the areas along the road having more than 100 employees.

Danish Road Directorate has sent out letters to each household when there would be work in their area (along M3). It has also been possible to find up-dated information at the homepage of Danish Road Directorate on the work along M3.

Figure 2.2. Construction work along M3 – demolition of an old bridge. Saturday morning, 7 o’clock. Neighbours from the area were invited to watch the explosion and later have breakfast at Danish Road Directorate.

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3.

NOISE ABATEMENT

3.1NOISE MAPPING

The issue of traffic noise was the greatest concern of the neighbours living close to M3. Therefore, an extremely important part of the project has been to reduce the noise exposure for the inhabitants living along M3.

To evaluate the noise related consequences, noise mapping along M3 was carried out in 2002 as a part of the Environmental Impact Assessment (see Figure 3.1). With noise mapping, noise exposure was calculated along M3. The calculations made it possible to evaluate the noise related consequences while changing a number of parameters such as traffic load, speed limits as well as implementing different noise reducing solutions. The construction price of different noise reducing solutions was evaluated for their effects so the noise related effect per invested DKK could be calculated. Based on the re-sults of these calculations it was decided to use primarily four metre high noise barriers, wherever there was a need [18].

A detailed noise map showed that if the former old and low noise barriers along the M3 were kept until 2010, there would have been approximately 6,300 dwellings (housing units) exposed to more than 55 dB of noise from the motorway traffic. In 2010, when the widening of the M3 was completed to six lanes and new noise barriers were built, only approximately 2,200 dwellings would be exposed to over 55 dB noise from the motorway.

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Figure 3.1. Noise mapping along M3 was carried out in 2002 as a part of the Environmental Im-pact Assessment.

3.2 NOISE BARRIER

Before the widening of M3, there were noise barriers in the form of old eternite panels that were 1.5-2.0 metres high (see Figure 3.2). In a few places there were newer barriers of about 3 metres in height, and in other places there was no noise protection at all.

<50 50 - 52 52 - 54 54 - 56 56 - 58 58 - 60 60 - 62 62 - 64 64 - 66 66 - 68 68 - 70 >70

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During the widening process, approximately 24 million Euros have been spent on noise abatement. This includes building more than 17 km of noise barriers at a height of 2-4 metres along the road. The noise barriers in many sections include a foundation on a retaining wall, therefore the total height in some places is nine metres above the adjacent residential areas (see Figure 3.3 Figure 3.4 and Figure 3.5).

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Figure 3.6 shows the back garden of a single family detached house situated along M3 before, during and after the widening of the motorway.

Figure 3.6. Back garden of a single family detached house situated along M3- before (upper left), during (bottom left) and after widening (bottom right).

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In order to have both efficient and economic long lasting solutions, the Danish Road Directorate put high demands for the selection criteria of noise barriers. These were:

 high efficiency at reducing and absorbing noise  long durability

 installation and maintenance from road side  reasonable price (10-12 mio. DKK/km)

Figure 3.7. Construction work seen from the road side.

To give access to sunlight some housing areas had a noise barrier where the upper metres of the barrier are transparent (Figure 3.8). Transparent noise barriers have been used in the majority of locations and especially on the bridges.

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Figure 3.8. At some places the upper part of the noise barriers were made from transparent acrylic plates.

The top sections of the noise barriers were designed with a tilted 10° towards M3 (Figure 3.9, Figure 3.10 and Figure 3.11). The barriers were constructed of 75 cm wide elements of perforated aluminium covering a core of absorbing mineral wool which prevents the noise from being reflected to neighbours, liv-ing on the opposite side of the road. The neighbourliv-ing side of the noise barri-ers was covered with espalier for plants which suits the wishes of the neigh-bours.

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Figure 3.10. Noise barriers seen from the neighbour side (during construction).

Figure 3.11. Noise barriers seen from the neighbour side (after construction).

As can be seen in Figure 3.12 and 3.13, on the bridges over crossing roads the noise barriers were made only from transparent modules for the bridges to look less massive as seen from the road crossing below.

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Figure 3.12. On the bridges over crossing roads, noise barriers were made only from transparent modules.

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3.3 NOISE REDUCING PAVEMENTS

It has been decided to use a special type of road surface (noise reducing thin layer pavement) on M3 which reduced the noise by 2-3 dB compared to a standard reference pavement (Figure 3.14).

The noise reducing effect has been obtained by using a smaller size of stone than usual in the asphalt mix. Furthermore, there were small cavities on the surface which let the air pressure created by the tires, get away from the sur-face pavement more silently.

Figure 3.14. A special type of road surface (noise reducing thin layer pavement) on M3 reduced the noise by 2-3 dB compared a standard reference pavement.

3.4SOUND INSULATION OF BUILDING FACADE

Mounting noise barriers alone cannot provide sufficient noise protection in all places along the M3 e.g. buildings in

several levels. Thus there has been a need for supplementing the sound insu-lation of building façades.

In order to pinpoint relevant housing areas for supplementary sound insula-tion, new noise calculations were carried out in 2006, where designed noise barriers and the noise reducing pavement was a part of the input to the calcu-lations.

Danish Road Directorate offered to subsidize sound insulation of building fa-cades for all the houses along the M3, which have been built before 1st April 1984, exposed to noise above 60 dB and having legal permission to be used all the year round. An additional condition was that a noise consultant must visit the house to describe what needs to be done in each house. Subsidies range between 50-90% of the entire noise reducing insulation costs to a max-imum amount 86.200 DKK per dwelling. Obtaining a quotation from a

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contrac-tor had to be done by the house owner. Subsidies were paid after approval had been obtained from the Danish Road Directorate. The conditions were described in detail in [19]. In total, 135 residences were offered subsidies for sound insulation of their building façade. Figure 3.15 shows en example of a building having façade insulation in the form of glass covering of the balcony. By using the noise abatement methods that have been described above, sig-nificant improvements of the noise condition after the widening of M3 have been obtained.

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4.

MATERIAL AND METHODS

The noise annoyance investigation was a pre and post-study, containing the

response from people who live along M3 and are exposed to noise from the motorway. Subjective responses were collected by two mail questionnaires that were carried out in the periods October-November 2003 and November-December 2009. The pre-study was carried out in a period where it was known by the public that the M3 motorway would be widened to six lanes and where the first public hearings had been organized. The post-study was con-ducted around a year after the construction work including the noise abate-ment measures was finished. Noise levels from road traffic were calculated at the same periods when the pre and post-questionnaires were sent out. This chapter describes the material and methods used to carry out the inves-tigation. In the following subsections; selection criteria of the study ar-ea/sample, development, pilot testing, distribution of the questionnaire, noise level calculations and statistical treatment of the data will be given.

CONSIDERATIONS:

Pre and post-questionnaire enquiries were carried out at the same season (late autumn, early winter) of the year letting people answer the questions un-der similar physical conditions (open versus closed windows).

Post-questionnaires have been sent out one year after the widening of M3 was completed. This gave people the possibility to experience the noise envi-ronment after the traffic and the urban conditions have normalized. The post-questionnaire can be seen in English translation in Appendix A and in the original Danish version in Appendix B.

Only persons over the age of 18 years were asked to fill in the questionnaire. Both pre and post-questionnaires were sent to all the addresses that are pri-marily used for residence in each of the selected areas. It was clearly stated in the covering letter that the unanswered questionnaire should be returned in the enclosed pre-paid envelope by putting a tick on the letter, if the house at the address was used for business purposes.

4.1STUDY AREA AND STUDY SAMPLE

This section gives an introduction to the survey areas to which the question-naires were sent. The criterion for the selection of residential areas was that each area should comprise;

 House type (single family detached houses, terraced houses)  No apartment blocks

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 With/without noise contribution from another large main road

 With/without change of noise contribution from M3 due to the widening of the motorway

 East/West of M3 (frequency of wind from different directions)

 No industrial or commercial areas, or areas dominated by shops and simi-lar buildings

It was decided to include six residential areas in order to give a good repre-sentation and fulfil the above criteria as well as possible. Figure 4.1 illustrates the location of the six survey areas from A to F.

A

C

D

E

F

B

MO TO RV EJ E4 7/E 55 MO TO RV EJ E47 /E55 MO TO RV EJ E4 7/E 55

Figure 4.1. Map where survey areas from A to F are shown. The areas belong to Gladsaxe, Herlev og Rødovre municipalities.

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For all of the six areas, app 50% of the houses were primarily one floor (with a basement) single-family detached houses.

AREA A

Area A is situated in Bagsværd just northwest of the M3 and is further bound-ed by Gladsaxe Møllevej, Buddinge Hovbound-edgade, Vibevænget, Rylevænget, Grævlingestien and Hermelinvænget. The accommodation is primarily single-family detached houses and terraced houses between Grævlingestien and Espegårdsvej. M3 in this area is placed on a high embankment and has a 1.8 metres high barrier of eternite plates in the pre-situation. The distance from the M3 to the nearest accommodation is approx. ten metres, the furthest it is around 450 metres from the motorway. Seven to eight hundred metres from the area in the western direction is the Hillerød motorway and the area is bounded towards East by Buddinge Hovedgade, which has considerable traf-fic load. (Response rate: pre-questionnaire 77.5%, post-questionnaire; 60.6%). Typical pictures from area after the widening are shown in Figure 4.2.

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AREA B

The area is in Søborg just southeast of the M3, and just southeast of area A. The area is limited by Udmarken, Buddinge Hovedgade, Stengårds Allé, Klausdalsbrovej, Gladsaxe Møllevej, Ræveholmen, Rensdyrvej and

Mårvænget. There are some terraced houses, but mostly the accommodation consists of single-family detached houses. The M3 in area B is on an em-bankment with a noise barrier of 1.8 metres in the pre-situation. The distance to the nearest accommodation is approx. 10 metres and to the furthest ac-commodation approx. 520 metres. The area is divided into two by Buddinge Hovedgade and Gladsaxe Møllevej. (Response rate: pre-questionnaire 70%, post-questionnaire; 60.9%). Typical pictures from area after the widening are shown in Figure 4.3.

Figure 4.3. Typical pictures from area B after the widening of M3.

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AREA C

Area C is situated in Herlev west of the M3 and southeast of Herlev Ringvej. The area is limited by Kagså, Ring 3, Tornerosevej, Elverparken, Nøkkedalen, and Hyldemorsvej. The southern part of the area is dominated by a large area of terraced houses and there is also an area of terraced houses in the north-ern corner. The remainder consists of single-family detached houses. A large part of the area is on a slope, which faces the M3. There are no noise barriers in the pre- situation. The house closest to the M3 is 75 metres away and the furthest house is 625 metres away. (Response rate: pre-questionnaire 76%, post-questionnaire; 68%). Typical pictures from the area after the widening are shown in Figure 4.4.

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AREA D

Area D is situated just south of area C, on the other side of Elverparken. Apart from the park, the area is limited by Ederlandsvej, Kagså, the M3, Herlev Hovedgade, Hyrdindestien and Tornerosevej. The area is dominated by sin-gle-family detached houses and a few terraced houses. Apart from M3 which is situated on an embankment and is in the pre-situation protected on a part of the stretch by a noise barrier of 1.8 metres height, the nearest roads are Herlev Hovedgade and Ring 3, both highly busy major roads. The house closest to the M3 is approx. 15 metres away, and the house furthest away is approx. 750 metres away. (Response rate: pre-questionnaire 66.5%, post-questionnaire; 66.8%). Typical pictures from the area after the widening are shown in Figure 4.5.

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AREA E

Area E lies in Mørkhøj, east of the M3 and directly across from area D. The area is limited by M3, Stavnsbjerg Allé, Ilbjerg Allé and Lillegårds Allé. The area only has single-family detached houses. The area is relatively protected from noise from other major roads. However, Mørkhøjvej is just a few rows of houses away. The nearest house is 70 metres from the M3, and the furthest house is 875 metres away. (Response rate: pre-questionnaire 68%, post-questionnaire; 66%). Typical pictures from the area after the widening are shown in Figure 4.6.

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AREA F

The area is in Rødovre on the other side of the Vestvolden with regard to M3, and thus in the pre situation protected from noise by the earthwork and the green areas. Apart from Vestvolden, the area is limited by Ejbyvej, Grønne-marksvej, Ringstrupvej, Bjødstrupvej, Borgmester Gustav Jensens Vej, Kors-dalsvej and Rødovre Parkvej. The southern part of the area has terraced houses, whereas the area north of Lucernevej mainly consists of single-family detached houses. Tårnvej, which apart from the M3 is the only major road nearby, is some 100 metres from the area. The nearest houses are 280 me-tres from the motorway and those furthest away are 850 meme-tres away. (Re-sponse rate: pre-questionnaire 66%). The post questionnaire has not been conducted in this area since there has been a delay in construction work be-cause of an ongoing planning on how to connect the road to another new mo-torway. Typical pictures from the area after the widening are shown in Figure 4.7.

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4.2QUESTIONNAIRE

In this section the method for designing and conducting the questionnaire sur-vey is presented. The structure and content of the questionnaire is described. Pilot testing, distribution process and data processing are explained in detail. As previously mentioned, the English translation of the questionnaire and the original Danish version are included as Appendix A and B respectively with their accompanying covering letter and reminder.

4.2.1STRUCTURE AND CONTENT

The questionnaire survey derived from an international standard [1] and was further developed with support of a group of experts (see Preface for the names of the members of the expert group). The draft questionnaire was sent to the expert group for their comments and their comments were used to im-prove the questionnaire further.

The questionnaire employed both numerical and verbal scales. A 10-point rat-ing scale was used to indicate satisfaction with the home or neighbourhood, and to rate bother, annoyance, disturbance caused both by noise in general and specifically noise from M3. The scale ranked from 0 to 10, where 0 was equivalent to ‘not at all annoyed’ and 10 equivalent to ‘extremely annoyed’ [1]. Noise sensitivity was also measured on a five-point verbal scale from 1=’very insensitive’ to 4=’very sensitive’ in both pre and post-questionnaires.

The questions on annoyance from road traffic noise were posed as: "Thinking about the last 12 months when you are at home, how much does noise from…….bother, disturb, or annoy you?" The question was a Danish transla-tion of the questransla-tion proposed in [1].

The same phrase was used to ask about annoyance indoors but with refer-ence to open and closed window. Questions were also posed on how long the respondents had lived at their present address, the number of members in their family, age, gender and household income.

The questions in the questionnaire filled six full A3 pages. The questionnaire was printed in black on two folded and stapled sheets of white paper, making a small booklet.

Apart from the questionnaire itself, the respondents received a covering letter explaining that the survey was a part of a comprehensive investigation carried out by the Danish Road Directorate. The aim of the investigation was ex-plained in the letter together with some practical information such as the deadline for returning the questionnaire and who should completed it (by a grown-up person over 18 years of age living in the dwelling). It was clearly stated that the Danish Road Directorate guarantees that all personal infor-mation will be treated in full confidence.

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Pre-questionnaire (October-November 2003)

The pre-questionnaire survey was carried out by Atkins Denmark for the Dan-ish Road Directorate in the period October-November 2003. In total 1,200 questionnaires covering six neighbourhoods (A, B, C, D, E and F) were dis-tributed in three municipalities namely; Rødovre, Herlev, Gladsaxe (see Fig-ure 4.1). Reminders were sent out to households that had not responded after three weeks. The response percentage was 63.6% before reminder letters were sent out. A total of 848 responses corresponding to 70.7% were re-ceived after the reminder was sent.

The questionnaire included 43 questions which have been divided into six sections namely:

1) annoyance from road traffic in general 2) noise annoyance from road traffic specifically 3) noise from other roads

4) facts/conditions about respondent’s residence 5) what can be done tp reduce road traffic noise 6) information on respondents themselves

Of the 43 questions, fourteen questions were presented to the respondents with an additional response category ‘other’, where the respondents could specify their definition of ‘other’. The final question of the questionnaire was reserved to allow respondents to give their overall comments. All written an-swers and comments were treated manually.

Post-questionnaire (November-December 2009 )

Six years after the first survey, in the period November-December 2009, a post-questionnaire survey has been carried out by the Danish Road Direc-torate. This questionnaire survey employed the same methodology as the first survey. In total, 986 questionnaires covering five neighbourhoods were dis-tributed to three municipalities (Rødovre, Herlev, Gladsaxe) to the same ad-dresses that were used in the first investigation (Figure 4.8). Households not responding after three weeks received an additional reminder. In total, 636 re-sponses, corresponding to 64.5% were received after the reminding letter had been sent out. The reason why the questionnaire was only distributed to five areas instead of six is that the road construction work in Area F was post-poned for a significant period to allow time for the planning of how to connect the road to neighbouring roads. Fourteen properties that were expropriated during the widening of M3 were also excluded during the post-study.

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Figure 4.8. Post-questionnaires ready to be posted, October 2009

The questionnaire included forty seven questions. In order to be able to com-pare results and have information about the widening, a new section (widen-ing of M3) consist(widen-ing of four questions was added to the post-questionnaire. One of these questions was about whether the respondent had participated to the previous enquiry regarding the widening of M3. The other three questions were about communication between the respondents and the Danish Road Directorate/contractors during the planning phase and the construction pro-cess.

Out of forty seven questions, sixteen questions were presented to the re-spondents with a response category ‘other’.

4.2.2 PILOT TESTING

In order to validate the survey procedure and to ensure that instructions were clear and specific, a pre-pilot test with project group members and a pilot test with 35 subjects was carried out prior to each questionnaire survey. Final ad-justments were made after the pilot testing.

4.2.3 DISTRIBUTION

All the questionnaires were sent to private addresses on the same day by na-tional mail delivery together with a covering letter and a pre-paid envelop (see Figure 4.9).

The questionnaires were all individually numbered, allowing the answers to be linked to calculated noise levels (LAeq,24) at the individual addresses and re-minder letters .

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Figure 4.9. Questionnaire, covering letter, pre-paid envelope.

4.2.4DATA PROCESSING

All the questionnaires returned were checked manually before they were sent for optical scanning. The optical scanning was carried out by the Danish IT Centre for Education and Research (UNI-C). This ensured fewer errors than if the responses were typed manually into a database. The coding procedure was also carried out by UNI-C. In order to ensure that the data and coding is correct, randomly selected questionnaires have also been checked manually. Data from scanned questionnaires were saved as SPSS (a commercial statis-tical analysis software program) data files.

4.3CALCULATIONS OF NOISE EXPOSURE

Before the widening of M3, noise level calculations have been carried out for the selected six residential areas (A, B, C, D, E, F - see Figure 4.1) by using a 3D calculation model that is built into SoundPLAN version 6.2.

In the model, input data regarding information on ground, road construction, traffic, noise barriers and buildings was based on Road Directorate’s digital ground planner (DGP), digital map and height models.

The noise level calculations were based on the common Danish version of the Nordic calculation method for road traffic noise (NBV96) [20], [21], [22] and [23]. The calculations were made before NORD2000 was introduced as the mandatory new prediction method.

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Noise level calculations for pre-study were carried out with traffic quantity and speed from year 2000, which corresponds to the traffic model that was used in relation to Environmental Impact Assessments (EIA) that was carried out by the Danish Road Directorate in 2002.

For post-study noise level calculations, the addresses in the residential areas from A to E were delivered by the Danish Road Directorate. The investigation contained 986 addresses in total. Based on National Survey and Cadastre calculated addresses coordinates (CAC), the relevant building polygons have been appointed in the digital base map. The individual building polygons were split into façade parts and a calculation point at a distance of two metres from the façade in the middle of each façade part was made. A minimum façade length of 4 metres has been decided to avoid calculation points at smaller building offsets etc. The calculation points have been numbered so the point (façade) facing M3 and having the shortest distance to M3 is given index 1. The following points are indicated clockwise. An example for placement of po-sitions of calculation points is shown in Figure 4.10.

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Calculation height has been set at two metres above the ground. The calcu-lated noise level LAeq,24h contains reflection contribution from the building fa-çade (The effect of reflection (- 3 dB) was subtracted from the noise levels during data treatment).

Noise exposure has been defined as the energy equivalent A-weighted sound pressure level over 24 hours (LAeq,24h). For each of the four calculation points per house, noise level LAeq,24h has been calculated both as the total noise level and as the noise level from M3, the main road and the local road alone. As seen in an example in Figure 4.10: Herlev Hovedgade is the main road and Tuskhøjen and Havfruevej the local roads. In this analysis it has been decided to use the noise levels at the façade (without reflection from the façade) of each building facing M3, referring to the read calculation points marked num-ber one in Figure 4.10. A typical example for main road and local roads is shown in Figure 4.11 and Figure 4.12 respectively.

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5.

RESULTS

 In this chapter, results of the investigation are given in seven groups, namely;

 study area  study population

 annoyance from road traffic  annoyance from road traffic noise  noise abatement

 communication process

 change regarding noise environment

The headings in this chapter are shown with the corresponding question numbers from the questionnaire, for example 5.2.1 Age (Q37). As mentioned previously the pre-questionnaire can be seen in the appendices.

All data analyses were carried out using the statistical program SPSS version 18.

In this first analysis of the respondents’ answers to the questionnaires it has been decided to present the results using descriptive statistics in the form of frequency and percentage distribution. Verbal data was treated manually, by grouping the answers and taking their appearing frequency into account.

5.1NOISE LEVELS IN THE STUDY AREAS

Noise exposure levels were calculated as the energy equivalent A- weighted sound pressure level over 24 hours (LAeq,24h) (see Section 4.3 for calculation of noise exposure) for each area separately. In the following, the percentage of households exposed to different noise levels is presented for each of the six study areas. Both the total noise levels as well as the individual contributions from M3, other main roads and local roads are presented. In each figure, both the noise in the pre and post-situation are presented as outdoor noise levels.

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5.1.1AREA A

Figure 5.1. Area A, calculated noise levels in dB outside the house, (M: M3 alone).

Figure 5.1. shows that the noise from M3 is reduced in area A after the widen-ing of the motorway and establishment of noise barriers etc. At the outset, 7% of the dwellings were exposed to more than 60 dB and in the post-situation this does not apply to any dwellings. Before the re-construction of the M3, 48% were between 55 and 60 dB. This is reduced to 12%. In the after-situation 82% of the dwellings are under 55 dB.

The noise exposure from other main roads in area A is shown in Figure 5.2. The contribution from other main roads is nearly the same in the before and after-situation. Around 90% of the dwellings are exposed to rather low noise levels under 45 dB from these other main roads, so they only have a marginal influence on the general noise levels in the area.

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Figure 5.2. Area A, calculated noise levels in dB outside the house, (O: Other main roads alone).

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In Figure 5.3, the noise exposure from local roads in the area is presented. Also here there is only a marginal difference between the before and the after-situation. However, the local roads have a larger influence on the noise in the area than the other main roads. Comparing the three figures for M3, other main roads and local roads, it can be clearly be seen that M3 is the far the most important source to noise exposure in area A.

Finally, the total noise exposure, predicted as the sum of the noise from the three road types can be seen in Figure 5.4 where the contribution from the M3 has by far the largest impact. There is a significant reduction in the total noise exposure in the after-situation. No dwellings are exposed to 60 dB or more. 63% were previously exposed to 55 to 60 dB; this is reduced to 47%. At the same time, a large number of dwellings end in the lower noise interval 50 to 55 dB before it was 28% and this increases to 46%.

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5.1.2 AREA B

The noise exposure in area B is presented in the four figures below which show that the main noise source in area B also is M3 and the general situa-tion is very similar to area A.

Figure 5.5. Area B, calculated noise levels in dB outside the house, (M: M3 alone).

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Figure 5.7. Area B, calculated noise levels in dB outside the house, (L: Local street alone).

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5.1.3AREA C

The noise in area C can be seen in the four figures below.

Figure 5.9. Area C, calculated noise levels in dB outside the house, (M: M3 alone).

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Figure 5.11. Area C, calculated noise levels in dB outside the house, (L: Local street alone).

Figure 5.12. Area C, calculated noise levels in dB outside the house, (T: Total).

In Figure 5.12. it can be seen that the noise reduction in area C is more significant than in areas A and B.

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5.1.4AREA D

The noise in area D can be seen in the four figures below.

Figure 5.13. Area D, calculated noise levels in dB outside the house, (M: M3 alone).

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Figure 5.15. Area D, calculated noise levels in dB outside the house, (L: Local street alone).

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5.1.5 AREA E

The noise in area E can be seen in the four figures below.

Figure 5.17. Area E, calculated noise levels in dB outside the house, (M: M3 alone).

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Figure 5.19. Area E, calculated noise levels in dB outside the house, (L: Local street alone).

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5.1.6 AREA F

The noise in area F in the before situation can be seen in the four figures be-low.

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Figure 5.23. Area F, calculated noise levels in dB outside the house, (L: Local street alone).

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Area F is situated at the eastern side of the motorway and there is a 280 m wide green recreational area in between. As for the other five areas also in area F, M3 is the main contributor to noise. Predictions for the after-situation have not been made as area F was excluded in the post-study. However, the noise levels in area F are significantly lower than in the other five areas. Near-ly all dwellings are exposed to less than 55 dB in the before-situation. The reason for that could be the green area between the motorway and the dwell-ings.

5.1.7TOTAL NOISE IN ALL SIX AREAS

In the four figures below, the noise is presented for all six areas. In the follow-ing Sections 5.2 to 5.7, the results of the two questionnaires are presented as totals for all six areas. Therefore, the figures below represent the noise expo-sure for all the respondents in the before and after-situations.

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Figure 5.26. All six areas, calculated noise levels in dB outside the house, (O: Other main roads alone).

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Figure 5.28. All six areas, calculated noise levels in dB outside the house, (T: Total).

Figure 5.28 shows the total noise exposure on all the dwellings in the six areas. In the after-situation, no dwellings are over 60 dB. 22% are between 55 and 60 dB, but this is a significant reduction from the 45% in the before-situation. Around 50% of all dwellings were under 55dB in the before-situation and this has increased to around 78% in the after-situation after the widening of the ring motorway.

5.2 STUDY POPULATION

This section covers information about the study population before and after the extension of M3. Not all respondents have answered all the questions. Therefore, the total number of respondents varies somewhat from question to question. In the pstudy 848, in the post- study 636 questionnaires were re-ceived.

5.2.1 AGE (Q37)

In question 37, the respondents were asked to state in which year they were born. The answers were converted to their age based on the year when the questionnaires were sent. The survey only included persons above the age of 18 years. The results are shown in Table 5.1 and Figure 5.29.

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Age

Frequency Percentage [%]

Before After Before After

18-30 39 17 4.6 2.7 31-40 181 95 21.6 15.3 41-50 204 160 24.3 25.7 51-60 152 129 18.2 20.7 61-70 120 102 14.4 16.4 71-80 105 74 12.4 11.9 81-90 38 45 4.4 7.2 Total number of respondents 839 622

Table 5.1. Responses to the question “What year were you born?” (Converted to age).

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The percentage of people at the age of 18-40 years decreased, while the per-centage of people at the age of 40-70 and 81-90 slightly increased during the period of 2003-2009. This can be interpreted that the population got slightly older along M3 during the period between pre and post-study. The age group of 41-50 has the highest percentage by app 25%, while age group of 18-30 has the lowest percentage by 3-5%, which can be explained by income differ-ences between the groups. Increase in house prices makes it difficult for younger age groups to be able to afford to live in a house.

5.2.2GENDER (Q38)

In question 38, the respondents were asked to state their gender. The results are shown in Table 5.2 and Figure 5.30.

Frequency Percentage [%]

Before After Before After

Female 344 304 41.4 48.6

Male 486 322 58.6 51.4

Total number of

respondents 830 626

Table 5.2. Responses to the question “What is your gender?”.

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As can be seen from the above table and figure, according to the collected re-sponses there is a 7% increase of female responding population and vice verse on the male population between 2003 and 2009.

5.2.3INCOME (Q40)

In question 40, the respondents were asked to state what their monthly household income is before tax. The results are shown in Table 5.3 and Figure 5.31.

61 respondents from the pstudy, 50 respondents from the post-study re-fused to answer this question, mainly because they found the question objec-tionable on the basis that it is too personal and some of them stated that they could not see any relation between their income and how much they are an-noyed from the traffic noise. Since there was a high number of respondents who refused to answer, a new response category as ‘refuse to answer’ was added to the table and the figure.

Frequency Percentage [%]

Before After Before After

0 - 20.000 171 112 20.2 17.6 20.001 - 50.000 378 205 44.6 32.2 50.001 - 100.000 226 238 26.7 37.4 > 100.000 12 29 1.4 4.6 Refused to answer 61 50 7.2 8.2 Total number of respondents 787 584

Table 5.3. Responses to the question “What is your monthly household income (total monthly income before tax for all in the household)?” (The amounts are in Danish Crowns).

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Figure 5.31. Responses to the question “What is your monthly household income (total monthly in-come before tax for all in the household)?”.

From the figure it can be seen that the survey population received higher in-comes during the period from 2003-2009.

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5.2.4SENSITIVITY TO NOISE (Q41)

In question 41, the respondents were asked to state how sensitive they are to noise. The results are shown in Table 5.4 and Figure 5.32.

Frequency Percentage [%]

Before After Before After

Very insensitive 18 15 2.1 2.4

Relatively insensitive 107 86 12.7 13.7

Normal 604 440 71.9 70.3

Relatively sensitive 84 62 10.2 9.9

Very sensitive 25 23 3 3.7

Total number of

respond-ents 840 626

Table 5.4. Responses to the question “How sensitive are you to noise?”.

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From the figure it can clearly be seen that there is almost no difference be-tween the noise sensitivity of the pre and post-study population. And in both situations, more than 70% of the respondents describe themselves as neither sensitive nor insensitive to noise, while only 3% of the same population de-scribe themselves as very sensitive.

5.2.5NUMBER OF PEOPLE PERMANENTLY LIVING IN THE RESIDENCE (Q43)

In question 43, the respondents were asked to state how many people per-manently live in their residence. The results are shown in Table 5.5 and Fig-ure 5.33.

Frequency Percentage [%]

Before After Before After

1 138 102 16.5 16.4 2 340 253 40.6 40.6 3 133 90 15.9 14.4 4 183 139 21.8 22.3 5 35 35 4.2 5.6 More than 5 9 4 1.1 0.6 Total number of respondents 838 623

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Figure 5.33. Responses to the question “How many people permanently live in your residence?”.

As can be seen from the above figure, in general two people, living in a resi-dence is almost twice as common as four people in their resiresi-dence, which is the second most stated category. There is almost no difference between pre and post-study population regarding to how many people permanently live in their residence.

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5.2.6CHILDREN IN THE RESIDENCE (Q39)

In question 39, the respondents were asked to state whether or not there are children at the age of 10 or younger in their residence. The results are shown in Table 5.6 and Figure 5.34.

Frequency Percentage [%]

Before After Before After

No 618 481 73.5 76.8

Yes 223 145 26.5 23.2

Total number of

respondents 841 626

Table 5.6. Responses to the question “Are there any children at the age of 10 or younger in your residence?”

Figure 5.34. Responses to the question “Are there any children at the age of 10 or younger in your residence?”.

Approximately 70% of the respondents do not have children at the age of 10 or younger.

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5.2.7TYPE OF RESIDENCE (Q18)

In question 18, the respondents were asked to state which type of residence they live in. The results are shown in Table 5.7 and Figure 5.35.

Frequency Percentage [%]

Before After Before After

House /villa, 1 floor 451 345 53.2 54.2

House /villa, 2 floor 158 145 18.7 22.8

Row house, 1 floor 81 42 9.6 6.6

Row house, 2 floor 139 88 16.4 13.8

Apartment 1 0 0.1 0

Others 14 16 1.7 2.5

Total number of

respondents 844 636

Table 5.7. Responses to the question “Which type of residence do you live in?”.

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The respondents are living in single family in one - two floor detached houses or row houses. There is nearly no difference between the before and the after situation.

5.2.8OWNERSHIP OF THE RESIDENCE (Q19)

In question 19, the respondents were asked to state who owns their resi-dence. The results are shown in Table 5.8 and Figure 5.36.

Frequency Percentage [%]

Before After Before After

Privately owned 752 577 89.0 91.3 Multi-ownership scheme 3 2 0.4 0.3 Rental 88 51 10.4 8.1 Other 2 2 0.2 0.3 Total number of respondents 845 632

Table 5.8. Responses to the question “Who owns your residence?”

Figure 5.36. Responses to the question “Who owns your residence?”.

Approximately 90% of the residences are privately owned, while around 10% are rented. The situation is almost similar in the pre-and post study period.

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5.2.9 YEARS IN PRESENT HOME (Q42)

In question 42, the respondents were asked to state how long they have been living in their residence. The results are shown in Table 5.9 and Figure 5.37.

Frequency Percentage [%]

Before After Before After

0-2 years 76 63 9.1 10.0 3-6 years 134 67 16.0 10.7 7-10 years 108 60 12.9 9.6 > 10 years 521 438 62.1 69.7 Total number of respondents 839 628

Table 5.9. Responses to the question “How long have you been living in your residence?”.

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More than 60% of the survey population has been leaving in their residence more than 10 years. There is a slight increase in the percentage of people liv-ing in their homes for more than 10 years in the post-study. 0-2 years and a large part of the 3-6 years’ group did not participated in the pre-study, since there is six years in between pre- and post studies. More then 70% of the population have received both pre- and post questionnaires.

5.2.10PLANS ABOUT MOVING (Q44, Q45)

In question 44, the respondents were asked to state whether they are plan-ning to move to another residence within the next few years. The results are shown in Table 5.10 and Figure 5.38.

Frequency Percentage [%]

Before After Before After

No 608 474 72.9 75.7

Yes 84 63 10.1 10.1

Don't know 142 89 17 14.2

Total number of

respondents 834 626

Table 5.10. Responses to the question “Are you planning to move to another residence in the coming few years?”

Figure 5.38. Responses to the question “Are you planning to move to another residence in the coming few years?”.

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More than 70% of the respondents are not planning to move from their hous-es. There is app 3% increase at the post-studihous-es. There is no change in the percentages of respondents who are planning to move. And there is a slightly decrease in the percentage of respondents who do not know.

In question 45, the respondents were asked to state what the most important reason is, if they are planning to move. This corresponds to 10% of the re-spondents who answered in the previous question that they are planning to move. The respondents were allowed to put more than one mark in the re-sponse categories. The results are shown in Table 5.11 and Figure 5.39.

Frequency Percentage [%]

Before After Before After

Want to have another house

condition (size, ownership) 112 101 13.2 15.9

Want to live closer to work 9 5 1.1 0.8

Traffic noise 192 88 22.7 13.8

Vibration from road traffic 53 17 6.3 2.7

Dust, smell from road traffic 92 43 10.9 6.8

Unsafe to go out because of

road traffic 18 9 2.1 1.4

Want to live in an other

neigh-bourhood 29 25 3.4 3.9

Want better outdoor

surround-ings 57 29 6.7 4.6

Want to live in a neighbour-hood which has better institu-tions

1 5 0.1 0.8

Want to live in a neighbour-hood which has better free time offers

2 4 0.2 0.6

Others 54 38 6.4 6

Total number of respondents --- ---

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Figure 5.39. Responses to the question “If you are planning to move, what is the most important reason?”.

Traffic noise was the main reason (23%) for people to have plans to move in the pre- study and this decreased to 14% in the post-study. Another road traf-fic related response category dust/smell because of road traftraf-fic also de-creased after the extension of M3.

5.2.11 PARTICIPATION IN THE PRE-QUESTIONNAIRE (Q46)

In question 46, the respondents were asked to state whether

t

hey had partici-pated in the previous questionnaire investigation regarding noise before the widening of Motorway 3. The results are shown in Table 5.12 and Figure 5.40.

Frequency Percentage [%]

Before After Before After

No --- 247 --- 39.8

Yes --- 234 --- 37.7

Don't know --- 140 --- 22.5

Total number of

respondents --- 621

Table 5.12. Responses to the question “Did you participate to the previous questionnaire investigation regarding noise before the widening of Motorway (M3)?”.

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Figure 5.40. Responses to the question “Did you participate in the previous questionnaire investigation regarding noise before the widening of Motorway (M3)?”.

38% of the respondents stated that they participated in the pre-study, while 23% mentioned that they do not know. Probably, the real participation from the same residence is somewhere between the sum of these two values (38-60%) since the participation of another person living at the same address is included in do not know option. There is in most areas an ongoing process of people moving to new homes for different reasons. Therefore it cannot be expected that it was exactly the same population who lived in the six areas in the before and in the after-situation. In the survey, the answers from all the respondents are included, both the people who participated in both the sur-veys and the ones who only participated in either the before or the after-survey.

The description of the respondents in the before and after-survey can be summarized as the following:

 Everybody lives in a villa or a row house.  90% owns their own dwelling.

 Over 60% have lived in their dwelling for more than 10 years.

 41% of the households have two inhabitants and 22% four inhabitants.

 In the post-study the respondents have lived longer in their dwelling.

(84)

 70% of the respondents have a normal sensitivity to noise.’  More people under 40 have participated in the pre-study.  More people over 40 have participated in the post-study.  The percentage of female respondents has increased from

41% to 49% in the post-study

 Approximately 70% of the respondents do not have children at the age of 10 or younger.

 In the post-study the respondents have somewhat higher income.

 38% of the respondents participated in both the pre- and post-study.

 Both in the pre and post-study 10% have plans to move.  In the pre-study 23% give noise as a reason for planning to

move. This has decreased to 14% in the post-study.

5.3ANNOYANCE FROM ROAD TRAFFIC (Q1)

In question 1, the respondents were asked to state when they are at home, in which way are they annoyed by road traffic, where they live. The respondents were allowed to put more than one mark in the response categories. The re-sults are shown in Table 5.13 and Figure 5.41. In Figure 5.

References

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