The automotive accidents with dangerous cargo endanger water resources, which can be achieved by the stroke of the products transported. In the catchment area of the Ribeira de Iguape Basin and South Coast these accidents are frequent, especially in the Régis Bittencourt highway (BR-116). Its loads can reach the water intakes before operators are warned, threatening the supply, and the assistance may delay or the rescue teams can reach the local without accurate information about the accident, damaging the whole service.
Considering the importance of the problem, from the point of view of both Civil Defence and the protection of water resources service, the Basin Committee of the Ribeira de Iguape River and Southern Coast of São Paulo State, Brazil, provided by the State Fund for Water Resources – FEHIDRO, is financing a project for the development of a computer system, covering a geographic information system and a support system to attend the accidents, throughout its whole area of competence, the Unit Water Resources Management n.11 – UGRHI-11, highlighted in Figure 4. The project was done in two stages: first, a conceptual model of the system was developed, detailed in modules to the central computer and handheld computers, and implemented programs for the database of Régis Bittencourt Highway (BR -116) and sub-basins affected by spills on this highway were developed. In the second phase, the model was revised, adjusting the program and expanding the database, now covering all paved roads, federal, state and municipal area UGRHI-11, as shown in Figure 5.
In modeling the database Management System for Automotive Accidents with Hazardous Cargo – GeoCap, sought to respond basic needs, as the most objectively way as possible, so the user of this system can operate it without difficulty. Mainly in Module Mobile, was prioritized to easier of operation, considering the need for quick operation without error by a user who is involved in the attending of an accident, which may present a risk to humans and the environment.
Another principle was for programming flexibility, allowing it to be started in 2009 with a small number of catchments, products and sub-basins in the BR-116 highway in the covered area UGRHI-11, and with more time and better data, expand and refine the database involving the entering new catchments, sub-basins and areas of intersection. This allowed in 2011 to extend to the state and local roads paved in UGRHI-11, and also transfer the program use for any other basin, without the need for new programming, just by adjusting the data.
An example of the flexibility, appointed at the first design of the database was to allow the numerical model of land, base for subdivision into sub-basins, can be easily updated, generating, if necessary, micro-basins smaller and / or with more accurate limits, to provide allowances for better decision making to attending the accidents and their communication.
Methods and procedures
In local visits to compare the reality with the cartographic representation, was noted the need to improve the representation of lineation to the guideline roads, even the BR116, the GIS-RB, as well as their representation altimetry and its intersection with the sub-basins. For this, was made a field survey of the entire path of paved roads within the UGRHI-11 (in 2009 on BR-116, the Sierra Itapecerica the border of Paraná, in the Barra do Turvo, in 2011 on the other roads paved UGRHI-11), with the support of Vilmar Antonio Rodrigues, research of Paulista State University – UNESP.
The equipment used was TOPCON HIPER LITE L1-L2 RTK, Receiver GPS RTK with dual frequency (L1 + L2) integrated (receiver, antenna, radio, battery and charger), with 40 universal channels, which tracks signals from GPS and GLONASS satellites, with update rate of 1 Hz. It has a horizontal accuracy of 3mm + 0.5ppm and a vertical of 5mm + 1.4ppm for static surveys and rapid-static, and horizontal of 10mm + 1.5ppm and vertical 20mm + 1.5ppm for kinematic surveys and RTK. The locations (latitude, longitude and altitude) were determined every five seconds path. The approximate speed route was 60km/h which allow getting the coordinates (x, y, z) each approximately 6 m.
System GeoCap Modules
The three modules that compose the system have the follow goals:
I – The mobile module, included in the handheld computer aims to guide and facilitate the initial procedures at the accident local, including communication with the central system.
II – The central module, maintained on a computer PC-Desktop, kept in the Operations Center, which feeds and receive such information, allowing the information integration about the accidents and standardization the information and procedures contained in handhelds computers.
III – The geographical information module, a member of the SIG-RB, assists in space decisions. The modules development:
Module I – Mobile
Installed on your handheld computer (currently HP iPAQ rx4200, but allowing immediate migration to others equipments) and external GPS, allows capturing the geographic coordinates through global positioning system GPS, processes the coordinates captured and returning the information pre-registered in a database, and provides information for communication with those responsible for catchments. The main menus and indicators can be seen in picture 1.
Picture 1: Main Screen Mobile Module.
Its operation is based on associating the geographic location of the accident with a particular area of intersection between the highway and a sub-basin, expressed as latitude and longitude, as shown in Picture 2:
Picture 2: Scheme of the coordinates of the area of intersection between highway and sub-basin.
Point 1: Initial coordinates of area
Y = Latitude X = Longitude
Point 2: Final coordinates of area
Y = Latitude X = Longitude
The mobile device GPS captures the coordinates of the location (measures in local of an accident) and checks which area is it, displaying information of catchments that are associated with this particular area.
The mobile device also serves as a source of standardized information, relating to dangerous cargo that are transported (toxicity, flammability) and the procedures to be adopted, depending on the type of load shed (isolation, evacuation of the area, etc..).
Picture 3: Flowchart of module mobile operation.
Picture 4: Localization of UGRHI-11 – Basin of the Ribeira de Iguape River and Southern Coast of São Paulo State.
Picture 5: Paved roads of UGRHI-11 searched to compose the database of GEOCAP system.
MODULE II – Central
The main function of the central module is to allow the user to register the essential information for the system operation and to transmit them to the mobile device. Furthermore, it allows a Control Center to maintain the information about the accident and support the actions of the attendants in the first line (firemen, police, road police, health attendants and assistance to users of the highway). It is kept in a PC- Desktop computer, with great processing and storage capacity. In this version is required a minimum configuration of Pentium III or higher with a minimum of 256MB of RAM, 512MB recommended, and available disk space of 100MB, and Windows XP operating system.
It consists of a database with seven related tables:
I – Table (CadCaptacao) – table of catchment points with their geographic coordinates and altitudes, user name and contact phone number in case of emergency arising from accidents that may affect the catchments point, exemplified in Picture 6.
Picture 6: Cadastre of catchments, central module.
II – Table (CadArea) – table with the areas bordering the track segments related to sub-basins with one or more capture points, with the risk of being affected by load shedding that occurred in their respective areas. Thus represent areas of intersection between the sub-basins and the track segments contained. These segments are defined by a rectangle, registered in the system by their geographical coordinates from the most north and west points, and from the most soth and east points. To better visualize the location of these areas along the BR-116 and state highways, it was decided to use, as a denomination, the acronym of the area and numbers corresponding to the initial and final miles (ex. 506-637).
III – Table (AssocCapt) – table with the association areas defined in Table CadArea with capture points table Cadcaptacao. This table is intended to provide the information about which capture points the spill may reach in a given segment.
IV – Table (CadProduto) – this table has as the main field the UN number to relate the 76 Guides and evacuation procedures, as Self-Protection Manual to Handling and Transport of Dangerous Cargo – PP4 (Indax, 1999).
V – Table (Guia) – this table has the procedure Guides, containing information relating to dangerous goods, classified by the UN number as: Potential Risks, Emergency Action and First Aid. It will be continuously updated according to new manuals.
VI – Table (Evacuacao) – table with guides evacuation procedures in the accident local, having as parameter the criteria of small and large leaks and risks of the product transported. The procedures take place in two stages:
- Area Isolation;
- Area Evacuation.
VII – Table (Ocorrencia) – table to register the accident. This table relates to the table CadArea through the field CodArea, which search the necessary information in the table AssocCapt to identify which catchments points subject to damage by the accident. In addition to the coordinates, date and time of the accident, there are fields to UN number, risk classification, subsidiary risk, number of risk and a field for comments.
Picture 7 shows the tables of database and relations between them.
Picture 7: Tables of central module.
Description of operations made by the Central Module:
Cadastre of Areas: Stores information related about the area mapping, such as starting and ending coordinates, name and comments.
Cadastre of Catchments: Stores information regarding catchments as coordinates, charge, phone number, etc..
Areas Associates: Allows the user to associate one or more catchments to a particular area.
UN Table: Register and consult regarding UN table, with information regarding dangerous products.
Guides Table: Register of Procedural Guides and consultation regarding actions and care to be provided according to the type of product.
Accidents Cadastre: Registration and query information about accidents and other occurrences. It can be feeded directly from the Desktop or from the information that has been collected on the mobile device.
MODULE III – Geographic Information
This module is the main tool for decision making, being held as part of the GIS-RB – Information System of Basin Ribeira de Iguape and South Coast, currently having cartographic accuracy equivalent to a scale of 1:50,000, with contour lines with contour interval of 20m.
This module is compose by seven information plans:
I – Lines drainage network with impedance, allowing to calculate the arrival time of a load shed by accident to the catchment point. The degree of certainty in the calculation of the arrival time is related to the accuracy of the information about the speed of the water body, informed in the GIS database. These speeds will be added in the next phase, which will be developed on the model of the hydrological basin. This will be more accurate as the best Digital Numerical Land Model.
II – Road design: conferred by differential GPS.
III – Digital Numerical Land Model: it had been reviewed in this project initially of 1:250.000 to 1:50.000, after increasing the resolution altimetry in regions flatter, adding map data with more details, usually 1:10.000 and field points, obtained by GPS accuracy. IV – Mosaic with georeferenced aerial photos, including a range of a mile in each side of the highway. Allows to observe comprehensively the area hit by accident. Currently it is only available in the fixed module, operated on the Desktop Central computer; becoming available to a mobile device with greater processing and storage it will be added to the mobile module.
V – Location of kilometric marks: raised from the DER website. It will be updated when more surveys are made recently by the concessionaire of the BR-116.
VI – Urban Areas: polygons with urban consolidated areas in UGRHI- 11.
VII – Water abstraction: starting with the catchment of SABESP, being added to the others as it is being consolidated the users’ registrations in GIS-RB.
The Information System of Basin Ribeira de Iguape and South Coast (SIG-RB) is improving the cartographic basemap in its successive versions, but the current cartographic precision available for almost the entire area UGRHI-1, only allows to generate a numerical land model with border lines with contour interval of 20m, which does not invalidate the conception and the algorithms used to GeoCap, but introduces an uncertainty in the exact location of the accident in relation to sub-basins.
This forced the direct survey of highways by GPS, allowing more exactly locations of the intersections areas between them and the limits of the sub-basins Theses data served to generate georeference aerial photos and a new partial MNT, using vectors of the raised road as axis. Still in the land work was possible to observe that the milestones marks are not correct, even in the BR-116 highway, with a difference in several cases of 300m, which invalidates any reference model of road based on these landmarks.
With an improvement of cartographic precision planialtimetric is possible to generate a numerical land model with better resolution, giving more accuracy to the calculations of water flow. With a better definition of flows and drainage lines, calculated by a GIS process, allow the generation of a more accurate map of micro basins, allowing to locate in smaller areas the accident points, facilitating control of their impacts on water resources. This has been done in the second phase of development of the system, recalculating the model based on better maps and data measured directly by GPS.
A fundamental problem still unsolved is the implementation of this system by the institutions responsible for the highways. Although it is fully functional under the technical point of view, it must be applied and adjusted, especially with regard to instructions to users and operating procedures, which should be the most suitable for use under conditions of stress and hurry, characteristics of accidents help.