Road Noise Management Tool: Mapping Action Areas classified by acoustical and non-acoustical priority criteria

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1 Edinburgh, Scotland EURONOISE 2009 October Road Noise Management Tool: Mapping Action Areas classified by acoustical and non-acoustical priority criteria Pilar Fernández Alcalá a Jose Luis Eguiguren b Itziar Aspuru c Manuel Vázquez d LABEIN-Tecnalia, Spain ABSTRACT This paper shows the solution designed by LABEIN-Tecnalia and proposed to the Road Construction Department of the Provincial Government of Bizkaia (Road Manager Administration), in order to facilitate the acoustical classification of priority action areas and to select the later corrective measures that would be implemented. This solution has been defined within the framework of the Noise Action Plan, and it aims to improve noise quality management of transport infrastructures network. This proposal allows the exploitation of the Strategic Noise Maps by means of a Management System PLCR (Plan de Lucha Contra el Ruido), owned by the Road Manager Administration. The output of the work is a Map containing Action Areas using as in-put information: a) the results derived from the Road s Strategic Noise Maps (daily average intensity > veh/day); and b) the data included into the Geographic Information System Plan de Lucha Contra el Ruido (area, population and buildings: residential, educational/schools and hospitals exposed to noise). To determine the optimal corrective measure to each particular situation, a top-down approach has been applied, based on acoustical and non-acoustical criteria. 1. INTRODUCTION In 2003, Spanish Law 37/2003 transferred the competence of the preparation of strategic noise maps and action plans to the managers of the noise sources. In this context, the Road Construction Department of the Regional Government of Bizkaia (DFB) runs the road infrastructures in Bizkaia. For this reason, during 2007, the DFB developed strategic noise maps for km of roads. These plans were subdivided into 22 units of strategic maps, or sections of roads with more than 16,000 veh / day. a address. pfernandez@labein.es b address. eguiguren@labein.es c address. iaspuru@labein.es d address. manu@labein.es

2 Nevertheless, Bizkaia has a high population density and roads bearing heavy traffic run near residential areas. That is why, there is a large number of situations in which acoustic quality objectives set by the state noise legislation are not met. These situations require corrective measures. In order to define a realistic Action Plan against noise and to adjust it to the economic resources available, a prioritization strategy is needed. This paper describes the methodology applied to classify these situations with special emphasis on the used technical criteria, as well as, on the weighting of criteria and other aspects related to noise exposure. This methodological development is part of the project "Plan to tackle Noise (PLCR), developed jointly between the DFB and LABEIN-Tecnalia. This collaboration was launched in 2005 and it is currently in force. In this project, an application based on GIS technology has been defined, so that DFB could implement the Strategic Noise maps for their roads in Bizkaia. Furthermore, with this application it is possible to obtain information about people, dwellings and areas exposed to noise, as well as other non acoustical information from roads, such as, name of the road, traffic level, velocity, type of pavement, year, Figure 1: PLCR application Nowadays, this application is very useful for the technical staff in DFB, in order to manage the noise scene caused by their roads in Bizkaia. 2. METHODOLOGY The regulatory developments of the current Spanish law, specify the need to define action plans against noise, aimed at achieving certain goals for sound quality. In the case of residential areas, the limits correspond to 65 dba for day and evening and 55 dba for the night. Noise protection special areas are defined taking into account the aforementioned limits, the information from strategic noise maps for Bizkaia s roads, (Regional Government of Bizkaia s roads competency) and the requirements of Directive 2002/49/EC.( 1 ) The studied roads in this first phase comprise areas with 22,500 exposed people to noise levels of Lden> 65 dba, in over 145 km of road. For this reason, corrective measures can not be developed simultaneously for all the involved areas at a time and it is necessary to establish an order of prioritization.

3 Figure 2: Regional Road Network with IMD> veh/day 1 Law 37/2003: Article 25th, Third Section, Chapter III The current methodology, enabled the prioritization and identification of areas were corrective measures are needed. This prioritization was based on the calculation of 3 factors associated with the assessment of the degree of noise impact: (1) the number of people exposed, (2) the area exposed and (3) the amount of residential and sensitive buildings exposed to noise. After the weighting of these three factors and their subsequent combination, a single overall indicator of noise impact is obtained. This global indicator enabled the prioritization of areas to implement corrective actions. The process for obtaining this overall indicator is explained in the following sections. A. Collection of the input data One key aspect to apply this decision-making methodology successfully was the availability of high-quality input data. These data provided high quality strategic noise maps, which are meant to support the development of Noise Action Plans. Because of the detailed input data, noise maps developed by DFB include a more ambitious documentation than the required by both, the Directive 2002/49/EC and by the Spanish law. In addition to the calculations of noise levels (isophone) at 4 meters high, facade noise levels (incident sound) at 4 meters height were also calculated. Thereby, they provided more precise information in relation to the exposed population. The analysis of the noise maps, suggested that the worst period was the night. Therefore, the night period was used for the development of the methodology, except in schools where, because of its predominant use of time, the day period was used.

4 Noise Map Facade Map Figure 3: Input data for the analysis (night period) B. Segmentation of the study area and calculation of noise impact degree factor s Once the strategic noise maps were obtained, the Historical Territory of Bizkaia was divided into squared cells of appropriate dimensions. For each of these cells we calculated the following factors associated with the degree of noise impact: Number of dwellings exposed Number of sensitive buildings (schools and hospitals) exposed Number of people exposed To obtain these three factors, the information from the results of façade noise mapping was used. These factors provide the information associated with the number of exposed buildings and exposed population at different levels of noise expressed in the following range of exposure: <50, 50-55, 55-60, 60-65, 65-70, >70. For the first two factors, the maximum value obtained at the most exposed façade was taken as the value associated with the noise impact of each building. In this case, besides the data from the noise maps at 4 metres high, noise impact above 4 metres was also taken into account. For the third factor, the residents of the exposed building were distributed proportionally at each point of noise façade calculation. The area exposed (in km 2 ) For the calculation of this factor the information from the results of noise mapping was used. This factor provides the information associated with the area exposed of the Historical Territory of Bizkaia at different levels of noise expressed in the following range of exposure: <50, 50-55, 55-60, 60-65, 65-70, >70. After the calculation of these four factors, all this information was centralized in a GIS file (shape). Thus, an analysis depending on the number of dwellings, sensitive buildings, area and population exposed to noise from transport infrastructure was obtained. C. Weighting factors In order to obtain the global indicator to represent the noise impact of each cell of the Bizkaia s Territory, each factor was assigned a weight. This weighting took into account what the relative importance of some factors over others was, as well as the exposure to certain noise levels (range of exposure) compared to other.

5 Data related to high levels of noise and to population (dwellings and people exposed to noise) were given more weight. This is the assessment index obtained: o I POB : Index to classify the cells according to the number of people exposed to noise o I RES : Index to classify the cells according to the number of dwellings exposed to noise o I SENS : Index to classify the cells according to the number of sensitive building exposed to noise o I SUP : Index to classify the cells according to the area exposed to noise D. The Global Index Once we had obtained the partial indexes for the different parameters, the last step was to encompass all these sub-indexes into a single Global Index. Once again, sub-indexes were weighed giving the higher value to the indexes related to the population exposed. I GLOBAL = I POB x Wpb+ I RES x Wres+ I SUP x Wsup+ I SENS x Wsen With this global index assigned to each cell, we made the classification of all analyzed cells, giving an order of prioritize to act on them by DFB. 3. RESULTS OF THE METHODOLOGY APPLIED The global indexes obtained were given a colour ranging from white to dark red according to the priority (being white low priority and red high priority). Then, each area in the map (representation of the Territory of Bizkaia) was coloured according to each global index, as shown in the figure below: Definition of action areas according to the Global Index Figure 4: Prioritization of action areas

6 However, the representation scale according to the Global Index is relative. Therefore, the meaning of the represented values in the scale only applies to the areas identified on the top of it. From this situation, The Department of Road Construction Department of the Regional Government of Bizkaia, has obtained the necessary information that will allow them to focus their resources on acoustic priority areas. In this point, they have an acoustical justification to begin to solve the noise problem caused by its regional network of roads. Besides the acoustical point of view there are other factors that affect in order to define the priority areas such as political and social factors, which could modify the priorities established by the acoustical criteria. 4. CONCLUSIONS The information resulting from the strategic noise maps elaborated by DFB in collaboration with LABEIN Tecnalia, enabled the definition of a methodology to prioritize acting areas defined in the Action Plan against noise fixed in DFB. This methodology provides the DFB with a strategy to optimize resources to mitigate the effects of noise caused by their road infrastructure, focusing financial resources for combating noise on areas considered as priority areas. A summary of the applied methodology is shown in the below graph:

7 Figure 5: Applied Methodology Within the scope of the PLCR project, after the application of this methodology, DFB analyzed the most proper action in each priority area through the application of another methodology, developed jointly with LABEIN-TECNALIA, which chooses the corrective measure that best fits to each area.

8 Nowadays, in this Department, within its interest to improve the way to manage the noise caused by their transport infrastructure network, they are implementing the above methodology for all roads in their jurisdiction with an IMD> 4000 veh / day. This way they are identifying new action areas and planning new corrective measures. ACKNOWLEDGMENTS The development of the methodology described in this paper has been possible thanks to the work carried out by the Road Construction Department of the Provincial Government of Bizkaia. We would also like to thank other departments of the Provincial Government of Bizkaia for the input data provided. REFERENCES 1. 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 y COMMISSION RECOMMENDATION (2003/613/EC) of 6 August 2003 concerning the guidelines on the revised interim computation methods for industrial noise, aircraft noise, road traffic noise and railway noise, and related emission data 2. Ley del Ruido 37/2003, de 17 de noviembre, del ruido 3. REAL DECRETO 1367/2007, de 19 de octubre, por el que se desarrolla la Ley 37/2003, de 17 de noviembre, del Ruido, en lo referente a zonificación acústica, objetivos de calidad y emisiones acústicas. 4. European Commission Working Group Assessment of Exposure to Noise (WG-AEN), Good Practice Guide for Strategic Noise Mapping and the Production of Associated Data on Noise Exposure. Version 2, January F. Segues and Maria Dolores Jiménez, Estudio para la determinación de las especificaciones técnicas en la elaboración de Mapas de Ruido de carreteras, Dirección General de Carreteras, Ministerio de Fomento y CEDEX 6. I. Aspuru, F. Segues, J. Rubio and M. Vazquez, The Process of Strategic Noise Mapping of Spanish Major Roads (EGRA): First Results Already Available, Euronoise I. Aspuru, F. Segues, J. Rubio y M. Vazquez, The process of Strategic Noise Mapping of Spanish Major Roads (EGRA): first results already available, Euronoise 2006, Tampere 8. P. Fernández, I. Garcia, M. Vazquez and I. Aspuru, EGRA: Elaboracion de Mapas Estrategicos en las Carreteras del Estado. Controlando la Coherencia, ICA María Dolores Jiménez, Jesús Rubio, Fernando Segués, Pilar Fernández. Do vacationers in Spain have the right to silence? Euronoise Noise mapping & modelling identification of noise hot-spots. QCity project. Markus Petz, Aasa Stenman, Peter Malm, Geert Desanghere. Feb Noise Mapping and Noise Scoring Software Techniques and Result Presentation. W.Probst. Euronoise 08 París 12. Strategies for noise action plans. P. Vos, De. Euronoise 08 París 13. Action planning procedures and realized action plans of municipalities and cities results from the implementation of END. M. Petz. Euronoise 08 París