Urban sound planning the SONORUS project

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1 Urban sound planning the SONORUS project Sónia ALVES 1 ; Beate ALTREUTHER 2 ; Joachim SCHEUREN 3 ; Wolfgang KROPP 4 ; Jens FORSSÉN Müller-BBM GmbH, Germany 4-5 Division of Applied Acoustics, Chalmers University of Technology, Gothenburg, Sweden ABSTRACT Sound is still insufficiently considered in most urban planning processes, resulting in unsatisfactory sonic environments that might even present health risks to citizens. No matter how complex and challenging the planning project might be, the creation or preservation of acoustically favorable environments should be part of urban planning. To support this process, the SONORUS project developed a holistic approach for urban sound planning and showed its benefits with practical test cases. The goal of the holistic approach is to facilitate the integration of sonic planning in an earlier stage of the planning process by combining different approaches and by providing new tools and methods, thus enabling urban planners to achieve healthy and supportive sound scenarios. Keywords: Sound, urban sound planning, planning solutions I-INCE Classification of Subjects Number(s): 52.9, INTRODUCTION In times of rapidly increasing population in urban areas (1), obtaining a good acoustic quality in urban areas is a major environmental task within the European Union that goes far beyond noise control. The task of urban sound planning requires a comprehensive view on the future development of cities, including the development of their transport and industrial infrastructure. To cope with the complexity of this task, the consequent application of a transdisciplinary approach is needed: urban and traffic planning, architectural aspects, acoustics, noise control, and soundscaping, as well as political and administrative processes and economic aspects, must be considered from the very beginning of the planning process. Urban planners actually are not educated in such a comprehensive way. Actually, two main obstacles constrain the attainment of healthy and acoustically favorable environments: the first is that acoustical aspects are typically involved only in an advanced planning or implementation stage (which is too late), and the second is that, at this point, the possible acoustic interventions are limited to noise control (which is too restricted in focus). As a consequence, any approaches to plan and achieve healthy and supportive sound scenarios should take into account acoustics from the very beginning of a project - in the best case, sound planning should already be included in the land-use planning stage. 2. THE SONORUS PROJECT 2.1 Idea and aims The publication of the European Noise Directive (END) in 2002 (2) was the EU s first step towards acoustically favorable and healthy environments for citizens by, first, stating the noise exposure and, second, by working out action plans where necessary. In the follow-up of this process and in order to 1 Sonia.Alves@mbbm.com 2 Beate.Altreuther@mbbm.com 3 Joachim.Scheuren@mbbm.com 4 jens.forssen@chalmers.se 5 wolfgang.kropp@chalmers.se 2319

2 enhance the possibilities of land-use and urban planning with respect to acoustic qualities of the environment, the European Union has started the project SONORUS urban sound planning (3). Within this project, the restrictions and drawbacks described above were to be overcome and better solutions in obtaining an acoustically favorable and healthy urban environment were to be worked out. A major aim of the project is to extend the classical noise abatement concept and to develop a comprehensive concept for noise control or, even better, for the acoustic design of urban environments adapted to the needs of citizens in the respective situation. In order to succeed, specialists are required with a broad competence covering areas such as acoustic prediction methods, noise control and soundscaping, but also aspects of city and traffic planning. However, specialists equipped with such a wide competence spectrum are hardly found. Therefore, the goal of SONORUS is to close this gap and bring together universities, enterprises and public organizations, that aim to offer training to urban planners in an arena of trans-disciplinary research, focusing on the integration of acoustics in the planning process. So, the task of the SONORUS urban sound planning project is to develop a new, holistic approach to create acoustically favorable and healthy environments and to educate future urban sound planners, that are able to cope with this comprehensive task. 2.2 Objectives The main objectives of the SONORUS Initial Training Network are: To conduct a research program, that addresses the key issues of modern urban planning with the goal of achieving a good acoustic outdoor environment, that is supportive for health and wellbeing. To implement a holistic approach to the planning of acoustic environments including diverse areas such as urban planning, traffic management, soundscaping and noise control. To enhance the European knowledge economy by providing trained and mobile researchers equipped with the skills necessary to create a paradigm shift in the handling of transportation noise issues in urban areas and thus reverse the trend of a deteriorating acoustic outdoor environment in urban areas. 2.3 Project structure The SONORUS project is an EU FP7 Marie Curie Initial Training Network, where Early Stage Researchers (ESRs) were educated as future urban sound planners. The project has three pillars: education, research, and application, these will be described in more detail in section 3. This is a joint project with nine full partners to undertake the education and research of the ESRs and four associated (city) partners to provide test cases for the application of the urban sound planning concept as well as practical experience with the urban planning offices structure. The project started in 2011 with the recruitment of in total 14 ESRs: engineers, architects and acousticians. In the three years of their participation, the ESRs had the opportunity to participate in summer schools, work on diverse research projects- usually combined with a PhD work and perform research visits as well as apply their findings at test cases. In September 2016, the SONORUS project will present the main results in an international symposium Urban SOUND Planning in Munich that will be open to public participation (3). 3. THE ELEMENTS OF SONORUS 3.1 Education: initial training network As explained above, up to now universities do not offer a specific training to integrate the knowledge of urban planners, architects, acousticians and public administration etc. This actually results in a very specific focus of all stakeholders involved in urban planning, restricted to their respective fields of activity. In their formation as urban sound planners, besides the research work at their home institution the ESRs underwent a close curriculum of university classes, summer schools with final exams and research visits covering the topics of planning skills, acoustic knowledge, insight into planning processes from the city partners and from a consultant s perspective as well as public outreach and leadership skills. A crucial part of the ESRs education consisted in the teaching of planning skills to supply the required knowledge on city planning, traffic planning as well as on cost benefit calculations. Public 2320

3 outreach skills incorporated introduction to project management, teambuilding and leadership as well as the training of communication skills to enhance communication between traditionally diverse groups such as engineers, city planners, and architects. 3.2 Research: new tools for sound planning The second pillar of SONORUS, research, aims to achieve new methods and tools to enable the urban sound planners to consider and present acoustics adequately within urban planning. New research results, providing advanced prediction methods e.g. for quiet areas, enhance the possibilities to design high quality residential areas by enabling the urban planners to assess new and/or uncommon measures. In this context, the further development of auralisation methods and tools performed within the SONORUS project gets important: auralisation, preferably combined with visualization, is a crucial prerequisite when designing acoustic environments and/or presenting new urban sound planning concepts to an auditorium. With the further development of soundscaping, newly emerged evaluation and design methods for an acoustic environment, based on the perception of people, can be established as standard working tools. 3.3 Application: holistic concept The ESRs skills acquired during education as well as the methods and tools developed in the research parts of the project were to be tested, assessed (and refined, if necessary), by applying them to the test cases provided by the project s city partners (cf. section 4). The scope of the so-called holistic approach in SONORUS was to find optimum solutions, which were adapted to the requirements of the respective test case. This was accomplished by combining the adequate tools and methods obtained in the research part of the project, in order to achieve a long term and overall improvement of the acoustic environment. The basic principle of holistic approach in urban sound planning is to avoid or reduce unwanted sounds ( noise ) and to preserve or even enhance wanted sounds. Furthermore, a prioritization of actions is important, especially for the case of unwanted sound (cf. Figure 1). Wanted sounds in certain cases might even be used to mask unwanted sounds (see e.g. some suggestions for the Brighton test case in section 4.2). Figure 1 Holistic concept: prioritization of actions concerning unwanted sounds (noise). A detailed description of the holistic approach as well as a catalog of measures for each step according to Figure 1 can be found in (4). 4. TEST CASE STUDIES The SONORUS project s research outcomes for urban sound planning and the holistic concept were applied to the test sites provided by the city partners. These test sites showed a wide spread in their specific character and challenges, they ranged from a completely new urban structure in Gothenburg Frihamnen area to existing urban structures with wide range (Antwerp) or local character (Brighton, Rome). The characteristics and solutions applied to the test sites are described in the following sections. A comprehensive analysis of the inclusion of the holistic urban sound planning concept into the general urban planning process and its practical implementation at the test sites is discussed in (5). 2321

4 4.1 Antwerp Ring roads and Rivierenhof park The area proposed by the city is generally affected by intense road traffic noise from different road infrastructures: two major highways and one local ring road (cf. Figure 2). The high noise levels affect residential areas and one of the urban parks of the city. Figure 2 Aerial view of traffic road node in Antwerp (provided by the City of Antwerp) Each location demanded a different approach: the residential area required noise engineering control measures to protect the residents of the existing buildings (Nr. 1 in Figure 3), whereas the planning of new residential buildings (Nr. 2 in Figure 3) was discussed with the urban planning team. This gave the opportunity to include an urban sound planning approach, where the new buildings were studied in their spatial distribution, considering the creation of closed or semi-closed courtyards, the creation of quiet sides and the integration of green elements. The analysis of Rivierenhof Park (Nr. 3 in Figure 3) included a dual approach, too: a perceptual analysis of the park users and, on the other hand, an analysis of the noise levels at the different areas of the park. Based on the results, a new distribution of activities was suggested for the park - depending on noise levels, topographical elements and existing infrastructures. Figure 3 General map of the site: 1- existing residential area, 2 new residential area, 3 - Rivierenhof Park Also, as the park is crossed by a two-lane road with intense traffic, affecting the usability of the space as a restorative environment, a comprehensive study including a FDTD (Finite-difference time-domain) analysis was conducted to find an optimized solution (cf. Figure 4). 2322

5 Figure 4 - Noise exposure along the cross section at 1.5 m height. a) Scenario 1. b) Scenario 2. From (5). It is concluded that a combination of noise abatement solutions (suppression of one lane and deviation of the traffic to neighbor roads, consideration of a low-noise road asphalt, including low noise vegetated barriers close to the road) can reduce the noise level considerably. Another specific problem was the connection of the park with the city that at the moment is done exclusively using the bridge Turnhoutsebaan. Despite the spatial proximity, this bridge is exposed to very high noise levels, is visually unpleasant and unsafe. The approach of the group was to study solutions to restore the function of this bridge as a pleasant, safe connection to the park that would be an anticipation of the park s green area function or an extension of the experience at the park. Thus, at Ghent University a study of the multisensorial perception of the urban environment, using a 3D engine game and Oculus Rift DK2, was conducted. This experience allowed to have a virtual walk (visual and audio experience) along the existing bridge and to test different solutions (6). 4.2 Brighton Valley Gardens Brighton & Hove City Council provided the Valley Gardens area (cf. Figure 5). This test site is a green area located in the city center, which was affected by intense road traffic from several traffic lanes surrounding the area and which had serious mobility barriers. Due to the many urban problems the site was far from achieving the potential as a meeting area both for residents and visitors and being a connection point for pedestrians. 2323

6 Figure 5 Valley Gardens test site. Copyright Google. Aerial view created using a licensed version of Google Earth Pro. The ESRs working group in this specific case had a dual approach: an analysis of the existing road traffic noise levels and a characterization of the sound environment, using acoustic metrics but also perception maps. These data confirmed, that road traffic noise in this case is the most dominant source and that it is perceived as inappropriate to Valley Gardens park area (cf. Figure 6). Figure 6 Valley Garden, southern part. Actual state (May 2016) Thus, several traffic scenarios studied together with the city were tested and an optimized solution was suggested (cf. Figure 7). 2324

7 Figure 7 New traffic model for Valley Gardens. Courtesy of Brighton & Hove City Council. From (5). As a complete soundscape characterization of the area is available, this information might be integrated in other measures, namely, masking of road sound with gravel paths in certain locations, the location of sound barriers/embankments or other traffic calming measures (5). 4.3 Gothenburg - Frihamnen Gothenburg Frihamnen is a former industrial area, which is located in an inner harbor in front of the city center. The area is part of a long-term development and will be transformed into a dense mixed-use area, which is intended to accommodate around new residents and work places (cf. Figures 8 and 9). Figure 8 Gothenburg city and Frihamnen area. From (5) 2325

8 Figure 9 Actual state of Frihamnen area (October 2015) The area is affected by intense road traffic, but also by a busy railway track. Additionally, the urban sound plan must consider the impact that the commutation movements to and from work and home will add in the future. Thus, at the department of Chalmers University, a dynamic traffic tool was developed to assess the impact of the transportation system and its effects on Frihamnen acoustic environment (cf. Figure 10). The dynamic traffic tool will be integrated with an auralization tool. It will be available to evaluate the impact of different road networks, both from the perspective of an urban planning team and other stakeholders such as future residents (5, 6). Figure 10 Contribution maps for traffic strategies. Base scenario (left), second scenario (right). From (5). Figure 11 Gothenburg-Eriksberg: Example for new urban development in the former harbor area. 2326

9 4.4 Rome The Roman Forum, Palatine and Coliseum area formed the SONORUS test site in Rome (cf. Figure 12). The area, although being one of the major archeological sites in the world, is inserted in the overall urban structure of present Rome city, therefore it is affected by traffic road and of course by the intense human activities, the latter being part of the history of the site. Figure 12 View of the archaeological/historical area One of the main objectives of the working group was to propose interventions, which would improve the sonic environment in particular and at the same time enhance the experience of the visitors by improving the overall quality of the area. Two strategies were followed: acoustic measurement campaigns, traffic counts and field surveys (to evaluate people s perception) at eight designated points and soundwalks performed inside and outside of the area of the Roman Forum and Palatine. These two approaches promoted a participatory process with the different users of the area, inclusive tourists, to assure that the future proposed actions respect the heritage and promote cultural and economic development of the site (cf. Figure 13). Figure 13 Survey campaign areas (left). Traffic counts and sound measurements points (right). From (5). The analysis of users soundscape perception in combination with sound pressure level measurements permitted the evaluation of adequacy of sounds and sound sources at the site with users expectations, thus facilitating the inclusion of sound planning in the overall planning process (5, 6). 2327

10 5. SUMMARY In times of increasing urban population, obtaining a good acoustic quality in urban areas has become a major environmental task within the European Union that goes far beyond noise control. This task requires a comprehensive view on the cities future development in a very early planning stage. It further needs planners that are familiar with the consequent application of a transdisciplinary approach: Urban and traffic planning, architectural aspects, noise control, and soundscaping, as well as political and administrative processes and economic aspects, must be considered. To cope with this challenge, within the EU s project SONORUS urban sound planner 14 students underwent a special education as Urban Sound Planners including the disciplines mentioned above. Within the project, new tools and methods for the adequate observance of acoustic aspects in urban planning were developed and applied to selected test cases in a holistic approach that aims to combine tools and methods, in order to achieve a long term and overall improvement of the acoustic environment. ACKNOWLEDGEMENTS This research received funding through the People Program (Marie Curie Actions) of the European Union s 7th Framework Program FP7/ under REA grant agreement n , SONORUS Urban Sound Planner. REFERENCES 1. Siemens. Como-Facts, Trends and Stories on Integrated Mobility. The future of getting around, issue 10, May European Noise Directive (END). Directive 2002/49/EC of the European Parliament and of the Council of 25 June 2002 relating to the assessment and management of environmental noise. Official Journal of the European Communities, L 189/12 EN, 18/07/ SONORUS project website Alves S, Altreuther B, Scheuren J. Holistic concept for urban sound planning applied to real sites. Proc FORUM ACUSTICUM 2014; 7-12 September 2014; Krakow, Poland Alves S, Estévez-Mauriz L, Aletta F, Echevarria-Sanchez G, Puyana Romero V. Towards the integration of urban sound planning in urban development processes: the study of four test sites within SONORUS project, Noise Mapping Journal 2015; V2(1); SONORUS Students Blog. online 28/04/2016,