Data analysis of noise complaints in Región Metropolitana, Chile

Transcription

1 PROCEEDINGS of the 22 nd International Congress on Acoustics Noise Assessment and Control: Paper ICA Data analysis of noise complaints in Región Metropolitana, Chile Ismael Gómez (a) (b), Max Glisser (a) (c), Camilo Padilla (a) (a) Gerard Ingeniería Acústica SpA (Control Acústico), Chile, (b) Universidad Tecnológica de Chile INACAP, Chile. (c) Acustical S.A., Chile. Abstract According to the First Environmental Perception Survey performed by the Chilean environmental authority in 2015, noise is the second greatest environmental problem in Santiago de Chile. Even though the road traffic noise, one of the main urban noise sources, has been quantified by the Ministerio del Medio Ambiente (MMA) with the Gran Santiago noise map, and the noise sources regulated by the Decreto Supremo N 38/2011 of MMA are controlled by the Superintendencia del Medio Ambiente; the behavioral noise sources, according to the Sistema Nacional de Información Ambiental definition, are regulated by Local Policies of each Municipality and formalized first mainly through Carabineros de Chile (CCh), and often this data is not included in official documentation. A more complete analysis of the noise complaints received by the institutions involved in his management allows identifying critical sectors, possible causes and solutions. For this reason, this study contains an analysis of the noise complaints received by CCh in Región Metropolitana between 2010 and 2015, submitting the total number of complaints, the monthly mean and the distribution by municipality, both in a 6 years period as well as for each year individually. The link to source code used for the process and analysis of data developed with the free access software "R" and its packages is presented. The information used in the analysis was requested by Ley de Transparencia. Keywords: noise, complaints, environmental, Chile.

2 Data analysis of noise complaints in Región Metropolitana, Chile 1 Introduction According to data provided by the Environmental Superintendence of the Chilean Government (SMA), the percentage of noise complaints in the country from January to March 2016 correspond to 52% of all environmental complaints, thus becoming the main source of complaints. May be worth noting that this percentage has been increasing from 39% in 2013 to 46% in 2014 and 48% in 2015 [1]. A sustained increase is observed. On the other hand, according to the first national survey of Environment, conducted by Chilean environmental authorities (MMA), the noise in Santiago is the second largest only behind air pollution pollutant. The survey information has been used by the MMA to feed and communicate their environmental public policies and strengthening the implementation [2]. Therefore the study and treatment of the noise problem in Chile and especially in Santiago is of high interest. Currently, behavioral noise sources lack of regulation at national level, since the Chilean legislation on environmental noise, Supreme Decree No. 38/11 MMA, excludes from its application, and given its characteristics are not deeply addressed in studies that seek to characterize the typical noise of a city, such as the Gran Santiago noise map [3]. Typically, these noise sources are related to domestic, commercial and small-scale recreational activities, developed sporadically. However, these noise sources are not free of generate a discomfort reaction in the community, which commonly results in complaints to the police institution in charge of local security or an agency of the municipal administration. According to government Environmental Noise Control Strategy [4], one of the work lines and goals is to implement a systematization of complaints. Therefore, it is necessary to implement a method to systematize this information in order to establish a regular diagnosis of the noise problems of the community. That is why in this work a compilation of available Región Metropolitana (RM) information from 2010 to 2015 from Carabineros de Chile (CCh) is made. CCh is the Chilean national police force, who has jurisdiction over the entire national territory of Chile and manages the noise complaints as it has the attribution to maintain order and public tranquility. From this information it is possible to segment the complaints by municipalities, which are the smallest administrative subdivision in Chile. They may contain towns, villages, hamlets as well as rural areas. In addition, there is information of the population projection for 2013 in RM, prepared by the Servicio de Salud Regional Ministerial Region Metropolitana based on information from the National Statistics Institute [5], with which it was possible to relate the number of complaints to the amount population demographically way to normalize the descriptor. 2

3 2 Method Under the support of the Chilean Government Law [6] on Access to Public Information, the database with the registration of the noise complaints of CCh in the RM from 2010 to 2015 was requested [7]. This period of 6 years is considered sufficiently representative for purposes of observe the temporal and geospatial behavior of complaints in the long run. The information obtained was reviewed in terms of content and format, allowing know the quality of the data and determine its potential usefulness and editing needs. The fields registered in the complaints database of CCh can be seen in Table 1. Worth mentioning that the complaints registered in the database were entered either by telephone or in person. Field MES AÑO TRIM DES_COMUNA DES_REGION DES_DELITO DENUNCIA Table 1: Fields for CCh complaints register. Explanation Month of the complaint Year of the complaint Quarter of the complaint Municipality where the complaint was made Region where the complaint was made Crime associated with the complaint Number of complaints in the same place Subsequently, for all generic steps involved in the process of data reading, cleanliness, order, calculations, analysis and visualization, the software freely available R was used [8] with different libraries generated by their community. The code developed for this and the raw data can be seen in this cited link 1, in order to do a reproducible research. The population data used in this study corresponds to the projected for 2013, from the 2002 census values [5]. It is considered appropriate to use these values as it corresponds to a central year of the studied period and also because it is used in conjunction with an average annual value of complaints. Meanwhile, for the geospatial graph generation associated with this indicator it took into account the political and administrative division defined by the municipalities, downloading polygon vector maps from the Map Collection of the Library of Congress of Chile [9]. 3 Results and Discussion 3.1 Complaints temporal analysis In Figure 1 is observed for each year the number of Total Noise Complaints (TNC) and the number of Places with Noise Complaints (PNC). The TNC for the period is 20,438, while the PNC add 9,347, although the latter could be repeated from year to year. Thus, there is an average of 2.2 complaints per place reported in the 6-year period studied

4 Figure 1: Total number of complaints and different places with complaints per year. Figure 1 shows a systematic decline of both the TNC as the PNC, reaching 40% and 19% reduction respectively, between 2010 and This behavior does not harmonize with increasing complaints of noise on the platform of the SMA and the results of surveys of MMA in relation to environmental noise perception by the community, as well as being atypical when compared with the experience gained elsewhere, such as New York [10], which presents a detailed system of entry and analysis reports, and where a progressive increase in the number of these is observed. In this scenario, the behavior observed in RM may be associated, on the one hand, to the fact that the reported cases are not being continuously monitored and/or recorded, either because they sometimes have less relevance compared to other types of emergencies or police contingencies, or due to the progressive reduction of available resources by system administrators, implying a continuing degradation of service platform and receiving complaints. In Figure 2 a typical Box and-whisker plot, with the median (black horizontal line) and mean (red dot), for each month considering TNC of the period is presented. Here it can be observed that the average monthly reports experience a decrease between April and September, reaching the highest values between October and March. This behavior may be related to decreased noise level at sensitive sites due to the use of closed windows given the climatic conditions of the autumn-winter season. Moreover, but related equally to weather conditions, the summer implies an increase in certain noisy activities (e.g. recreational, social, minor construction in housing, among others), which could increase behavioral noise sources. It is possible that the variable nature of these additional noisy activities in summer explain the greater dispersion observed for complaints of those months. 4

5 Figure 2: Box-and-Whisker plot with TNC for each month in the period. 3.2 Complaints geospatial analysis In Figure 3 it can be observed the annual average of complaints by municipality. Top considering all complaints (TNC) and down considering only the first complaint reported by each site (PNC). There is seen that the municipality of Santiago has the highest average annual PNC (103) and is also the second municipality with highest average annual TNC (246) in the study period. This result verifies that this municipality represents an area of high involvement in relation to noise complaints reported. On the other hand, even though Maipú municipality has the highest annual average of TNC (391), its annual average PNC reported (85) is lower, which implies that it presents on average of 4.6 complaints by place, unlike Santiago for the same index has a value equivalent to 2.4, which implies less frequency in the complaints made to the same place. After Maipú and Santiago, other municipalities with the highest value of TNC are Las Condes (246) and Puente Alto (242), which have an average rate of complaints by place of 2.6 and 2.4 respectively. Meanwhile, after Santiago, other municipalities with the highest values of PNC are Puente Alto (100) and Las Condes (95), repeating its appearance in the municipalities with most number of complaints. 5

6 Figure 3: Annual average of complaints by municipality. Then, in Figure 4 a map with the political administrative division considering only the 32 municipalities of the province of Santiago, and Puente Alto and San Bernardo (Gran Santiago Urbano), whose color indicates the average annual TNC per 100,000 inhabitants. Notes that the complaints percentage of these 34 municipalities is equivalent to 83% of the total, and that according to National Statistical Institute information projected for 2013, the population of these 34 municipalities corresponds to 87% of RM total. For a better visualization, Lo Barnechea municipality is not included, even though is considered in all calculations and analysis (index between 0 and 49). The figure shows that the municipalities with the highest average annual rate of TNC per 100,000 inhabitants are Independencia (260), Santiago (158), Ñuñoa (114) and Quinta Normal (111), all connected to each other and located in the central area. This information can be contrasted with Figure 3 in the sense that municipalities with high number of TNC and high population density, as Maipú, are not among the municipalities with more complaints per inhabitants. 6

7 Figure 4: TNC annual average per 100,000 inhabitants. 4 Conclusions and Proposals Using public information generated by CCh, a temporal and geospatial analysis of complaints associated with in RM was performed, observing the behavior of the Total Noise Complaints (TNC) and Places with Noise Complaints (PNC) indicators, in addition to the annual average TNC per 100,000 inhabitants. Geographically, 83% of complaints are concentrated in Gran Santiago Urbano corresponding to the 32 communes of the Province of Santiago, and Puente Alto and San Bernardo. This way, it is found that complaints in rural areas have a less significant presence. The municipalities with greatest PNC are, in descending order, Santiago, Puente Alto and Las Condes, these municipalities also has the biggest TNC values, after Maipú. Although Maipú has the largest TNC, the PNC value is significantly smaller than the three municipalities already mentioned, which implies a higher concentration of reported complaints in each place. Regarding the indicator of complaints received per number of inhabitants, Independencia, Santiago and Ñuñoa are the municipalities with the higher density of complaints per capita. The temporal analysis of the noise complaints shows a systematic shrinking from year to year. These results are not in line with the increase in complaints evidenced on the platform of the 7

8 SMA and the MMA perception of discomfort studies. In turn, this behavior is considered "irregular", as advanced reporting systems, such as the case of New York, indicate a steady increase in the total number of cases in consecutive years. This situation could be attributed to a flaw in the system, hitherto unknown, which can potentially be related to the priority given to these cases in respect of other emergencies or the available resources of the system, either in terms of trained staff or available communication channels, shelf registration, among others. Considering the above exposed, in addition to taking as reference the experience in other cases and the guidelines of the Environmental Noise Control Strategy of MMA [4], comes the need to optimize the current reporting system used by CCh, so that it has the capacity to carry out the record of all cases that want to be reported. In this area, the participation of local government as an institution responsible for such management, leading a unified noise nuisance complaints registration is required. This integrated record should follow a specific and transversal format for all municipalities, so that there is compatibility between their databases, which facilitates the development of further analysis and comparable results. On the other hand, it would be important to have information on complaints made to the different municipalities in the last years, especially of those with large annual average TNC per 100,000 inhabitants, to analyze their behavior as the municipalities receive an important portion of the complaints, which were not part of this analysis. The information currently associated with each complaint should be completed with additional background information related both to the denounced activity as the person or complainant entity, allowing to have valuable information for establishing strategies and management programs. The minimal information which it is considered relevant to register for each complaint can be observed in Table 2. Table 2: Suggested fields and details to register for each complaint. Item Field Details Complaint Date Hour, Day, Month and Year Location Street, Number, Municipality and Geographical coordinates 1) Construction 6) Loud Talking 2) Alarm 7) Animals Source type 3) Banging / Pounding 8) Specific equipment or categories 4) HVAC or Electric machine of building type generator equipment Source 9) Other 5) Loud Music Complainant Building type categories Personal / Organization information 1) Workshop / Factory 2) Commercial store 3) Educational center 4) Cultural center 5) Sport center 6) Religious building 7) Private residence 8) Street / Public space 9) Other Age, sex and occupation / Activity type and operating schedule 8

9 Additionally, the city administration must analyze this information systematically, considering temporal and geographical variables in the short and long term. This management will determine the areas with the highest amount, density or frequency of complaints, providing information relevant to the definition of control measures and best practices for the management of the issue and to evaluate its effectiveness. It is suggested that the results obtained are of public use, reported to the community through a dedicated website (e.g. that complies with the requirements of the information public access law [6]. An instance of this kind provides a clear sign of transparency, allowing, among other things, find the main activities that act as nuisance agents, evaluate municipal management in the area and establish a comparison between the indexes of their municipality and neighbor ones and the general indices of the city. References [1] Ministerio del Medio Ambiente, Gobierno de Chile, Gestión del Control del Ruido Ambiental en Chile", Seminario Ruido Ambiental MMA, [2] Ministerio del Medio Ambiente, Gobierno de Chile, Informe Primera Encuesta Nacional de Medio Ambiente, [3] Ministerio del Medio Ambiente, Gobierno de Chile, "Elaboración de mapa de ruido del Gran Santiago mediante software de modelación", [4] Ministerio de Medio Ambiente, Gobierno de Chile, Estrategia para la Gestión del Control de Ruido Ambiental ". [5] Instituto Nacional de Estadísticas, SEREMI de Salud RM, Dpto. Salud Pública y Planificación Sanitaria. Sub departamento de Gestión de Información y Estadística, "Proyección Población por comuna según sexo. Región Metropolitana. Año 2013", Enero [6] Ministerio Secretaría General de la Presidencia, Gobierno de Chile, Ley N Sobre Acceso a la Información Pública, Agosto [7] Departamento de Información Pública y Lobby, Carabineros de Chile, Certificado de Recepción de Solicitud de Información Pública N AD009W , Enero [8] R Foundation for Statistical Computing, R Development Core Team, R: A language and environment for statistical computing. Vienna, Austria, [9] Mapoteca de la Biblioteca del Congreso Nacional de Chile, División comunal: polígonos de las comunas de Chile, Marzo [10] N. D. S. Academy, NYC Data Science Academy Blog, "NYC noise complaint visualization", Noviembre Available: 9