Using GIS on Road Network

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GIS APPLICATIONS FOR ROAD NETWORK OF THE PHILIPPINES: A NEW TECHNOLOGY IN ROAD MANAGEMENT

Engr. Luz V. LAGUNZAD , MEngSci Engineer IV Planning Service Department of Public Works Works and Highways Bonifacio Drive, Port Area Metro Manila, Philippines Telephone No. (632) 304-3470 Fax No. (632) 304-3484 Email :[email protected]

Mr. Kevin MCPHERSON Consultant Scott Wilson Kirkpatrick & Co. Ltd. Road Information Management Management Support System System Department of Public Works and Highways Bonifacio Drive, Port Area Metro Manila, Philippines Telephone No. (632) 304-3087 Email: mcpherson.Kevin@dpwh [email protected] .gov.ph

Abstract: Two years ago the Department of Public Works and Highways (DPWH) started implementing a Geographic Information System (GIS) using the Global Positioning System (GPS) to survey the 29,000 kilometers of national road network and established an Environmental Scientific Research Institute (ESRI) shapefiles describing that network. Significant time and much effort was spent on the verification and validation of the GIS data. This is a fundamental data set that will be made available internally within the Department for different purposes. This paper describes how GPS, GIS and the traditional database applications will help in the management of the highway network using a common Locational Referencing System (LRS) that will integrate all data on road and bridge inventories. The LRS centerline survey uses uses a comprehensive comprehensive GPS and video for for the collection of road data. Once the centerline survey is undertaken, it will establish an accurate location for the identified nodes and sections to determine the exact length of our national road network. The data gathered from this survey will serve as the backbone to develop the DPWH’s GIS and other related applications. applicat ions.

1. INTRODUCTION Background

The original methods of locational referencing used by the DPWH were not suitable for comprehensive computerizat computerization ion of highway highway information. Many discrepancies were noted as to the exact position of the same feature as recorded by the different offices in the DPWH. This is because different organizational units within the DPWH had carried out independent survey activities with little attempt at coordination. coordination. This led to extensive collection and duplication of the same data for different different purposes. To solve solve this problem, problem, the Locational Referencing System (LRS) was used as the primary method to relate various types of road data. Before the actual LRS centerline survey started, a series of workshops was conducted by the DPWH Central Office/Road Information and Management Support System (RIMSS) project for the regional/district level engineers on how to properly identify “nodes” at road intersections, administrative boundaries, and “sections” which are the lengths of road measured along the centerline between nodes. In other words, a road section is a linear representation of a road’s center line and has a defined length and direction. direct ion.

Journal of the Eastern Asia Society for Transportation Studies, Vol.5, October, 2003

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The DPWH under the RIMSS project conducted a nationwide Locational Referencing System centerline survey for 29,000 km. of road network (see Figure 1). It combined Global Positioning System (GPS) and video for collection of data. The centerline survey was undertaken to establish an accurate location for the identified nodes and sections. There were 9,000 unique sections and 8,000 nodes. In addition, locations and digital photographs of around 20,000 kilometer posts were captured, along with video and roughness data for paved roads. The data collected was used to establish the exact length of the national road network. These data serve as the backbone for development of DPWH’s GIS and related applications.

Figure 1. Sample of Philippine National Road Network With the completion of the LRS, DPWH has begun the establishment of an enterprise-wide Geographic Information System (GIS). The LRS serves as the backbone of data for this GIS. It will enable implementation of embedded GIS, where the GIS and traditional databases combine to produce truly integrated applications. The same spatial representation of the road network is being used by all applications and will be used to manage various data on roads and bridge infrastructure, including condition, inventory, traffic, right-o f-way and locations. This information is then made available to planning, construction and maintenance processes within the DPWH through GIS-enabled client applications. Internet-based mapping services can also be made available to external stakeholders in future.

2. ROAD NETWORK ANALYSIS Locational Referencing System

The operational and planning analysis which accurately identify the National Road Network of the Philippines is the Locational Referencing System. It is defined as anything associated Journal of the Eastern Asia Society for Transportation Studies, Vol.5, October, 2003

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with the road network through the use of “nodes” and “ sections”. Nodes are defined as points in the road network. Typically these are intersections or administrative boundaries. Sections represent the road’s centerline between two nodes. A section’s limits and location are defined by the nodes that represent the end of the sections. (See Figure 2)

3. GIS DEVELOPMENT

A GPS centerline survey data was conducted to address the spatial data referencing needs for DPWH. This was used as a foundation for referencing all data collected and for displaying road data in the GIS format. This enhanced the Department’s ability to display data in an easily understood format and facilitate the interpretation of these data. The GPS centerline survey data supports and strengthen planning and decision support purposes. The survey also established the position of Locational Referencing Points (see Figure 5). These points are generally the existing kilometer posts along the road. The survey also collected video data of the road network and roughness data of the paved roads. The video data (see Figure 6) facilitated the verification of existing data and assists in the gathering of future data by the Central and Regional Office staff for identifying inventory features on or along a roadway. The video data also provides a historical record of visual features which can be used at a later date if needed. The data set obtained from the above survey is very large. It includes approximately 9,000 road sections, 8,000 nodes, 20,000 digital photographs, and 3,000 video files, as well as numerous database files. GIS provided the best mechanism for integrating all of the above data into a single environment and to enable spat ial querying and analysis of that data.

Figure 2. Sample of “Nodes and Sections” on Philippine National Road Network


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Figure 3 shows attributes of each road section as stored in the GIS. These include the unique Section Id, Start and End Node Ids, the DPWH Engineering District that is responsible for maintenance, a Road Id and Road Name, Functional Classification, and total length of section.

Figure 3 – Section Attributes

Figure 4 shows attributes of each node stored in the GIS. These include the unique Node Id, and references to digital photographs sketch maps where appropriate.

Figure 4 – Node Attributes Journal of the Eastern Asia Society for Transportation Studies, Vol.5, October, 2003

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Figure 5. Sample of Locational Reference Points on Philippine National Road Network

Figure 6 Sample Video Data for Philippine National Road Network


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4. INTEGRATING GIS IN APPLICATIONS

In DPWH, GIS supports many applications and functions. One of them is the management of the road network definition with associated inventory and condition data. Other major applications include the long and medium term planning of the national highway network, bridge management, environmental impact assessment and monitoring the exact locations of on-going road construction and maintenance projects. The Department is implementing off-the-shelf applications that use ESRI Map Objects technology to integrate the spatial and tabular data sources. The DPWH Road and Bridge Information Application (see Figure 7) will enable accurate mapping of road and bridge inventory through dynamic segmentation.

Figure 7. DPWH Road and Bridge Information Application with Embedded GIS


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It also allows integration of all Road and Bridge data within a single dat abase for use by other applications in future (see Figure 8).

Figure 8. Integrating Data through Databases and GIS

Figure 8. Integrating Data through Database and GIS

5. ENTERPRISE GIS

The Department is also implementing its enterprise GIS using ESRI ArcIMS on its internal network. It is using a combination of ArcGIS, ArcIMS and ArcSDE to provide internal GIS web services. These GIS services are being made available thru the Department’s Wide Area Network to its Central, Regional and District Offices. Recent developments in internet map service technology have made the deployment of GIS services and its applications relatively easy within large organizations like DPWH. A web-based front end is being established to make data available to a wide number of users in Central and Regional Offices, including those in Planning, Design, Construction and Maintenance functions. (See Figure 9).


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Figure 9. DPWH Enterprise GIS on the Internal Web

It also makes extensive use of ESRI’s metadata descriptions in XML (eXtensible Markup Language) to make the metadata easily available to users. (Please see Figure 10).

Figure 10 Metadata Available on the Internal Web


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This makes it simple for the GIS administrators to communicate easily with end users regarding timeliness and accuracy of the data. Also included are known data problems, and timetables for future update. A number of ArcIMS map services have been established, based on functional areas within the Department, including: (see Figure 10) Administrative Land Classification Road Network Socio-Environmental Transportation (Other) ArcIMS greatly eases the ability to make all of the Department’s spatial data available to staff who need to use it. The long-term intention is to make selected map services available on the internet to DPWH’s customers, however there are no immediate plans to do this.

6. CONCLUSION

An accurate Locational Referencing System (LRS) is fundamental to the storage of all data for the Philippine National Road Network. The sustainability of all aspects of the new data collection methods are critically dependent upon keeping the centerline survey up to date at all times. Nevertheless, survey updates are still very important, and responsibilities and updates procedures must be defined and managed to ensure that the centerline survey is always complete and also up to date. Geographic Information Systems (GIS) are key to making this data available to all end users who need access to it. Recent developments in GIS data integration and internet map service technology are making deployment of these applications relatively straightforward. REFERENCES a. Reports and Manuals RIMSS (1999) Locational Referencing System (LRS) and Data Collection Report

RIMSS, Africon Coffey (2000) Procedures and Validation Report: Philippine Road Centerline Survey. RIMSS (2000) LRS and Highway Infrastructure Data Report . RIMSS (2000) BIIP.

Implementation Plan for Specialized Surveys: LRS/Data Collection

b. Other document GIS Day 2000, Department-Wide GIS for DPWH


Using GIS on Road Network

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