Integrated System Approach for Municipal Pipeline Asset Management

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Integrated System Approach for Municipal Pipeline Asset Management Powered By Docstoc
					           North American Society for Trenchless Technology (NASTT)
                                 NO-DIG 2004

                                 New Orleans, Louisiana
                                   March 22-24, 2004




INTEGRATED SYSTEM APPROACH FOR MUNICIPAL PIPELINE
ASSET MANAGEMENT
Ting-Kwei Wang and Sunil K. Sinha
Civil and Environmental Engineering, Pennsylvania State University, University Park, 16802

ABSTRACT: A municipal assets management system consists of many components that are normally
owned and managed by the same agency (e.g., streets, culverts, water pipelines and sewer pipelines).
Among the municipal assets, some significant efforts have been made to develop management systems
to improve efficiency in utilizing limited municipal assets. However, there has been much less work done
to develop a “total” municipal infrastructure management methodology that ties these systems together.

The main objective of this paper is to provide municipal government with a methodology for integrating
different assets among various municipal improvement projects and coordinate project implementation to
reduce cost and disturbance. Two main parts of this research are network-level integration and project-
level integration. The network level integration focuses on one single asset, such as sanitary sewer
pipeline and uses the GIS software to select the pipelines that are required to be repaired. The project-
level integration uses the GIS software to create the buffer zone for maintenance after network-integration
and overlay other different assets (i.e. power, cable, gas, pavement, etc.) in the buffer zone. The
integrated system approach developed in this study for the management of municipal assets was applied
to five infrastructure components (water, sewer, gas, cable, and pavements) of the State College
municipal system in central Pennsylvania. The sample municipal application has showed that
coordinating project implementation is beneficial for municipal agencies and users.

INTRODUCTION
Municipal governments are continually investing large sums of money to maintain the physical and
operational quality of their infrastructure assets above minimum levels. A municipal assets management
system consists of many components that are normally owned and managed by the same agency (e.g.,
pavement, water pipelines and sewer pipelines). Thus, it is logical to expect that managing these
components in a coordinated manner is beneficial to both users and owners. Municipal infrastructure
management is essentially a set of activities associated with the process of maintaining, rehabilitating,
and reconstructing/replacing municipal assets in a cost-effective way. Thus, municipal governments need
tools that allow them to perform coordinated management of their assets and that provide the services
that the community expects of them within funding limits.

To improve the efficiency in utilization of limited resources, significant efforts have been made to develop
management systems for some individual municipal infrastructure components (e.g. pavement
management systems and pipeline management systems). Even if municipal governments have
information management or maintenance management systems for some municipal infrastructure
components, these systems are usually separate from each other. For example, a considerable amount
of research has been done, separately, in the areas of pavement management systems and pipeline
management systems. However, little research has been done to combine these two major management
systems and other municipal asset management systems. After an extensive review of the literature, it
was evident that more research is needed to develop a “total” municipal infrastructure management



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methodology for managing various municipal infrastructure components in an integrated manner.
Separate management systems in different assets are often incompatible in terms of location referencing
systems, analytical procedures, and data input/output format. Thus, data sharing and communication
among these systems become impractical and expensive. Sometimes project conflict (like water pipes
and sanitary sewer pipeline maintenance) may increase costs, spend more time and cause traffic
disturbance.


MUNICIPAL ASSET MANAGEMENT
Asset management involves processes of planning and monitoring physical assets during their useful
lives to an agency. Managing effectively requires an appropriate level of management interest and
concern be maintained well beyond the stage of acquisition. The objective of asset management is to
achieve the best possible match of assets with program delivery strategies. This is predicated on a critical
examination of alternatives to the use of assets. Asset management systems provide accurate and timely
information for effective decision-making. A complete system has five components.
        Facility inventory;
        Assessment of condition;
        Valuation;
        Operations, maintenance, repair and replacement management; and
        Analysis and evaluation including use, risk, and cost-effectiveness.

Municipal asset management (MAM) is a body of management practices that maximizes the cost-
effective use of capital assets over the life of the asset. Simply stated, it gets the most use out of each
asset over the life of the asset for the least long-term cost. Municipal capital assets include general
infrastructure, such as roads, bridges, water and sewer treatment plants, sewer collection systems,
airports, schools and storm water collection facilities, as opposed to financial assets or rolling stock. MAM
provides the systematic planning, acquisition, development, operation, maintenance and control of capital
assets. Asset management technology focuses on techniques, such as valuation, development,
utilization, prioritization, replace-versus repair decisions, and asset management systems.

Good asset management is built on carefully defined levels of service (LOS) applied to the design of the
asset and the maintenance of the asset. LOS statements become both design targets for new assets and
maintenance benchmarks for operations. LOS standards are the basis for establishing work processes
(step-by-step instructions for executing operations and maintenance tasks), which, in turn, help set
staffing and equipment levels and determine budget needs. Managers of municipal infrastructure assets
must also make different technical decisions regarding when and how to maintain, repair, or renew their
assets, while working with continuously-shrinking budgets. These managers must allocate funds among
competing yet deserving needs, often having to make decisions based on incomplete data. In addition,
the asset managers’ resources are being challenged from all sides: managers are also being asked to cut
costs, privatize operations, outsource responsibilities and reduce expenditures (Vanier, 1996). This makes
it extremely difficult for long-term decision-making in the area of municipal infrastructure management.

MUNICIPAL ASSET MANAGEMENT SYSTEMS
For the variety of municipal assets, efficient information management is the key to better decision making
for municipal infrastructure (Level, 1996). For many organizations, major issues of service delivery are
“repair and renew” rather than “design and build” (Johnson and Clayton, 1998). Engineers, technical staff,
administrators, and politicians all benefit if decisions about maintenance, repair, and renewal are based
on reliable data, solid engineering principles, and accepted economic values. Significant efforts have
been made to develop management systems to improve efficiency in utilizing limited municipal assets
(e.g. pavement management systems and pipeline management systems). However, there has been
much less work done to develop a “total” municipal infrastructure management methodology that ties
these systems together. Major advantages of integrated infrastructure management systems are as
follows (Gharaibeh, 1997).
      Integrated database and common linear referencing system;
      Compatible analytical procedures;
      Compatible output presentation methods;


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      Potential for reduced software development, maintenance, and operation costs; and potential for
      reduced training costs.
One of the early efforts in the area of urban infrastructure management was made by the Urban Institute
and the International City Management Association in the early 1970s to identify measures of
effectiveness for basic municipal services (e.g., transportation, solid waste collection, water supply,
sewage) (Measuring, 1974). However, the real-world use of these effectiveness measures is still largely
untested (Grigg, 1988). The need for seamless data integration, requirement for enhancement and
standardization of currently available tools were discussed by Vanier (2001).

With the booming of Information Technology, a Geographical Information System (GIS) is recognized as
an intelligent asset management tool (Ghosh, 1995). The system enables location specific information to
be stored, analyzed and displayed against a map background. Integrating asset management and GIS
systems allows input of asset spatial and attribute data with increased accuracy and time saving in
contrast to conventional keyboard entry methods (Howard, 1995). GIS is used to locate and inquire on
asset data and display of asset data such as age profits and items of high fault/maintenance history. The
advantages of transferring information to the GIS system are (Ellwood and McGregor, 1992):
1. Information contained within asset management databases can be presented visually by the mapping
    database
2. Programs developed within the Mapping System enable further analysis of data
3. Interrogation within the GIS system can be cross-checked against information within the Asset
    Management System to enhance reliability of result. The key point is to be able to easily and quickly
    identify the asset both in the office and in the field. GIS is used to illustrate asset age profiles and
    locate and inquiry to the asset attribute data files. A picture is worth a thousand words and a color
    picture is worth a million.
This paper describes a prototype methodology for managing multiple assets by using GIS software.

DESCRIPTION OF THE INTEGRATED METHODOLOGY
Municipal governments manage large and multiple assets. A major task of municipal managers is to
maintain these large assets above minimum performance standards set by the policy makers using a
limited budget. The theory of this thesis is that an integrated system approach to the management of
municipal assets provides a methodology to help municipal managers to make decisions. This integrated
and comprehensive methodology was developed for managing multiple municipal assets in a coordinated
and cost-effective manner. Henceforth, this methodology will be referred to as the “integrated
methodology.”

DEVELOPMENT OF THE INTEGRATED METHODOLOGY
An extensive review of the literature states no comprehensive methodology that is conceptually capable
of integrating the management process of many municipal infrastructure components. The importance of
developing an integrated municipal management system is also specified in previous research.

There are several aspects of infrastructure management integration considered in the integrated
methodology. The descriptions of the analytical procedures, data integration and presentation methods
use the geographic information system (GIS) software system that ties together and implements the data
and management procedures. Together these elements comprise the new methodology.
     Key features of this methodology are summarized as follows:
     Software system (GIS)
     Ranking maintenance priority for one single asset (Network-level integration)
     Coordination of project implementation (Project-level integration)

The aspects and the benefits of integration as considered in the integrated methodology are summarized
in Figure 1. The purpose of network-level integration is selecting one data set (such as sanitary sewer
pipe) and tries to detect the most emergent damage of the asset to do maintenance and repair. The
project-level integration includes identifying adjacent improvement projects from various infrastructure
components that can be implemented to reduce adjacent project disruptions. The project-level integration
is performed in a spatial manner using GIS capabilities. The integrated system approach developed in
this study for the management of assets was applied to five infrastructure components (pavement, power


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cable, sewer pipeline, storm water pipeline and water pipeline) of the asset management system in State
College in central Pennsylvania.
             Integrated                       Network-Level                     Project-Level
            Computerized                       Integration                       Integration
            System (GIS)

           Integrated database                Rank the repair                Do adjacent projects
          Compatible analytical                  priority                    Simultaneously to
               Procedure                     Based-on criteria                    reduce
           Compatible output                                                    Disruptions
                            Figure 1. Integration of Infrastructure Management
Assets selection
As mentioned before, pavement, sanitary sewer, water pipes, storm water pipes and power cables are
chosen in this research among multiple assets. Sanitary sewer pipes are selected as an example when
performing network-level analysis. Pavement, water pipes, storm water pipes and power cables are
considered as potential disturbance at project-level integration.

Data collection
This research was performed by receiving different data sets from various organizations. Pavements,
sanitary sewer and storm water pipes data sets are from Borough of State College, including both GIS
and AutoCAD format. The data for water pipe system was received from State College Borough Water
Authority and only AutoCAD format was available. For power cables, Allegheny Power provided
information for several blocks in downtown State College due to security reasons. Since this research
uses sanitary sewer pipes as an example to execute network-level integration, more detail information
was collected for sanitary sewer pipes in comparison with other assets.

Database development
Following the data collection is database development. As mentioned before, GIS is recognized as an
intelligent asset management tool and it supports multiple data sources and formats. An integrated
database with multiple assets information is developed by GIS in this research.

Network-level and project-level integration
Network-level and project-level are two analysis methods in this research. GIS is utilized at both network-
level and project-level analysis. The purpose of network-level integration is ranking the repair priority for
one single asset. The aim of project-level integration is reducing disturbance from other assets.

Final output
GIS can support not only multiple data formats but also multiple output formats, such as tabular and
graphical representation. Examples of representation will be shown in the following chapters. The
proposed system design for municipal infrastructure management is presented in Figure 2.




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                Figure 2. Proposed System Design for Municipal Infrastructure Management

SOFTWARE SYSTEM
This is a single system architecture that includes the combination of various infrastructure asset
management and information systems. This system incorporates several tools (e.g., data, analytical
methods, information presentation techniques) that extend the potential value of each management
system beyond its individual scope by allowing engineers and engineering managers to coordinate
decisions at the planning, management, and operational levels. Geographic Information Systems (GIS)
arise as a promising technology in this regard. There is a general consensus among GIS professionals
that GIS is a system of hardware, software, data, people, and institutional arrangements for storing,
analyzing, and presenting data referenced to geographic location. An essential tool for applying the new
municipal infrastructure management methodology efficiently is a computer software system that includes
a set of appropriate engineering, economic, and spatial methods.

GEOGRAPHIC INFORMATION SYSTEM
GIS combines layers of information about a place to give a better understanding of that place. What
layers of information should be combined depends on different purposes, such as finding the best
location for a new store, analyzing environmental damage, and viewing similar crimes in a city. Two main
advantages of GIS are improving organizational integration and making better decisions.

Organizational Integration Improvement
One of the main benefits of GIS is to improve management of organization and resources. A GIS can link
data sets together by common location data, such as addresses, which helps departments and agencies
share their data. By creating a shared database, one department can benefit from the work of another—
data can be collected once and utilized many times.

Intelligent Decision-Making
GIS is not just an automated decision support system but a tool to query, analyze, and map data in
support of the decision making process. For example, GIS can be used to help reach a decision about the
location of a new housing development that has minimal environmental impact, is located in a low-risk
area, and is close to a population center. The information can be presented succinctly and clearly in the
form of a map and accompanying report, allowing decision makers to focus on the real issues rather than
trying to understand the data. Because GIS products can be produced quickly, multiple scenarios can be
evaluated efficiently and effectively.

GIS Software
Environment Systems Research Institute (ESRITM) is recognized as the leading supplier of topologically
structured GIS packages. ArcInfoTM, ArcViewTM, ArcGISTM, MapObjectsTM, and IMS TM are leading
products of ESRITM (Tucker, 1999). ArcInfoTM and ArcViewTM are two popular products among them.
ArcViewTM 8.x is the newest version, which consists of ArcCatalogTM, ArcMapTM, and ArcToolboxTM LT.
These applications are stand alone and execute independently of each other. ArcCatalogTM is similar to
Windows ExplorerTM for ArcGISTM. It allows the user to view GIS data; preview geographic information;
view and edit metadata; work with tables; and define the schema structure for geographic data layers.
ArcMapTM provides mapping and editing functions as well as multiple window displays for map-based
analysis. ArcInfoTM 8.1 is the most powerful and functionally rich application in the ArcGISTM product
family. It includes all the ArcViewTM and ArcEditorTM modules, but adds advanced geoprocessing and data
conversion capabilities.

Multiple Data Source and Format
The advantage of GIS is the range of methods available to get data into a GIS includes keyboard entry,
digitizing, scanning and electronic data transfer. Then, methods of data editing and manipulation are
reviewed, including re-projection, transformation and edge matching. The whole process of data encoding
and editing is often called the “data stream”. This is outlined in Figure 3 Data in digital form needs to be
encoded to be compatible with the GIS being used. This would be a relatively straightforward exercise if
all GIS data used the same spatial and attribute data models. However, there are many different GIS data
sources and many different approaches to the handling of spatial and attribute data. The situation is being


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eased by the development of standards for spatial data encoding. Data received in this research contains
multiple formats and GIS can transfer different formats into GIS format.
                        M aps              S a te llite d a ta          D ig ita l d a ta        T a b u la r d a ta         S o ft id e a s



                          D ig itiz in g               S c a n n in g               D a ta tra n sfe r            K e y c o d in g




                                                                   D a ta c a p tu re

                                                                   E d it/c le a n in g

                                                                   R e -p ro je c tio n

                                                                  G e n e ra liz a tio n

                                                   E d g e m a tc h in g a n d ru b b e r sh e e tin g

                                                                        L a y e rin g

                                                           In te g ra te d G IS d a ta b a se


                                                    Figure 3. The Data Stream

NETWORK-LEVEL INTEGRATION
Municipal governments spend large sums of money each year in maintaining assets such as pavements,
sanitary sewer pipelines, and storm water pipelines. However, because of budget limitation each year,
they must detect the most emergent damage and then rank repair priority based on asset condition.
Traditionally, the process for identifying and tracking maintenance information has been through paper-
based documentation. Though useful, paper-based documents have some limitations in comparison to
the more visually detail GIS maps. GIS maps can present asset condition and location in order to help
decision makers. The network level integration focuses on selecting one asset and trying to find the most
emergent damage part of the asset requiring maintenance and repair. The first step establishes the
objectives and criteria for analysis. The second is data collection and preparation for analysis. Step three
focuses on data input and transfer. Step four is analysis for decision-making process. The final step is to
present the result.

CRITERIA AND OBJECTIVES ESTABLISHMENT FOR ANALYSIS
The main objective of this analysis is utilizing the GIS software to prioritize pipeline repair. The network-
level integration uses sanitary sewer pipelines as an example to analyze. After discussing the criteria for
analysis with the Borough of State College, two main factors are considered for decision-making: sanitary
sewer pipelines condition and pipe size. However, pipe condition is more significant than pipe size since
the main concern for maintenance is pipe condition. Pipe condition factor has higher priority than pipe
size factor when setting up the criteria for maintenance. Following the procedure for selecting and ranking
pipeline repair priority, the final decision making process should also consider the pavement condition
since the pavement will be affected during the progress of maintenance. Since it is efficient to repair the
pavement and pipeline at the same time, the final decision-making is a two-way process. If the
maintenance project is to repair pipes, pavement is also taken into consideration after the pipeline is
selected for repair. The same situation happened when the maintenance project is to repair pavement,
pipes are also considered for decision making. The decision-making process is showed in Figure 4.

DATA PREPARATION FOR SPACIAL ANALYSIS
Asset condition is the necessary information for maintenance. However, after discussing with the officers
at Borough of State College, there is no condition index available right now for sanitary sewer pipeline but
this research is under processing. The method used by Borough of State College is videotaping and
analyzing sanitary sewer pipelines condition. In order to present the convenience of GIS software, this
research will assume the condition index for sanitary sewer pipeline and the information is based on the




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repaired record. The range of condition index is from one to ten, which ten means the best condition and
one means the worst condition. The pipelines in worse condition have higher priority for maintenance.




                           Figure 4. Network-Level Decision Making Process

DATA TRANSFER AND INPUT
ArcInfoTM 8 supports viewing and transferring many data formats such as AutoCAD format. The data from
Borough of State College includes both GIS file and AutoCAD drawings of sewer pipes (Figure 5).




                  Figure 5. Sanitary Sewer Coverage is Exported from AutoCAD Drawing

In ArcMapTM, it is convenient to view each pipe’s condition by simple clicking and emerges a dialog box.
The dialog box will show each pipe’s location, pipe type, length, condition index, repair cost, etc. The
information presented in the dialog box is stored in the attribute table (see Figure 6).




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                                                Figure 6. Attribute Table
Items in the attribute table
This attribute table contains the information about features on a map, stored in rows and columns. Each
row relates to a single feature; each column contains the values for a single characteristic. Besides the
basic feature identification information stored in the attribute table, other information about assets
condition are as follows:
Traffic effect
Reducing traffic disturbance is a main concern when pipes are repaired. According to the comparative
traffic load, some streets are considered as “heavy roads” and need trenchless technology when
performing maintenance. Atherton Street, Beaver Avenue, College Avenue and University Drive are
defined as heavy roads by the Borough of State College.
Traffic control cost
It’s contractor’s responsibility to do traffic control and must meet PennDOT Publication. Usually traffic
control costs $400 US per day, including two flag people per eight hours a day, based on prevailing
wages, equipment, and set up time.
Pipe condition index
In order to illustrate the effect of pipe condition, this research assumes the pipeline index from one to ten.
The pipeline index means the condition of the pipeline, which number one represents the requirement for
immediate repair and number ten expresses the new pipe.
Pipe size
The diameter of the pipe, the unit is inch.
Pipe size index
The size of sanitary pipes ranges from 6 to 30 inch. To illustrate the effect of pipe size, this research
makes an assumption for pipe size index and transfers pipelines size into pipe size index.
Pipe type
This means the materials of the pipe, such as VCP, PVC, etc.
Purpose
The purpose of this repair or maintenance, such as reconstruction or rehabilitation
Buffer zone
If other assets (such as water pipes) are inside the buffer zone, they might be affected by sanitary sewer
pipes when performing maintenance; the unit of the radius is ft.
Technology
Trenchless and open-cut methods are utilized in this research. The Borough of State College sets a
higher priority to implementing trenchless technology when performing heavy roads maintenance.
Pipe repair unit cost
The pipe repair unit cost is based on trenchless or open-cut technology, material, etc. The unit is $/ft.
Total cost
It is the total repair cost of this pipe segment. The formula is:
                                          Total Cost = Unit Cost * Length

ANALYSIS FOR DECISION-MAKING PROCESS
When performing maintenance, the first process is to set the criteria. As mentioned earlier, pipe condition
index and pipe size index are recognized as the two main factors for decision-making. After editing the
data, the priority of sanitary sewer pipes can be shown by the sort descending function.




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According to the index system, the pipelines are in worse condition if the pipeline condition index is less
than or equal to three. If the Borough of State College decides to repair the pipes in worse condition in a
particular year, the pipelines with condition index less than or equal to three can be analyzed through
selecting these pipes to a new coverage. Figure 7 presents graphical representation of pipes in worse
condition at network-level. After selecting the pipes in worse condition, because the pipelines with larger
size are more significant than pipes with small size in the whole system, the next step is to rank the
pipeline priority based on the pipeline size index. The example of ranking the pipeline maintenance
priority based on the pipeline size index is presented in Figure 8. With the priority of pipeline
maintenance, the next process is to consider the effect of pavement. If the open-cut method is adopted,
the pavement will be affected.




            Figure 7. Graphical Representation of Pipes in Worse Condition at Network-Level




                             Figure 8. Rank the Priority based on Pipe Size Index

PROJECT-LEVEL INTEGRATION
Project-level integration includes identification of adjacent improvement projects from various
infrastructure components in a particular year that can be implemented simultaneously to reduce time,
cost and traffic disruptions. In the absence of coordination, conflicts in project implementation are likely to
occur. For example, pavement rehabilitation activities may be performed in an area, and then a few
months’ later rehabilitation activities are performed on a sanitary pipe located within the pavement area.
Obviously, such uncoordinated projects increase both agency and user costs. The Project-Level
Integration is performed by choosing several data sets and using GIS to do spatial analysis. The GIS
software can be used to integrate different data sets in a single map and show the geographic
relationships between different projects. This study uses pavements, storm water pipelines and sewer
water pipelines data sets. Figure 9 presents the framework of network-level integration.




                                              Paper G-4-02 - 9
                                     Figure 9. Project-Level Integration
After network-level is performed, the result presents the asset required to repair in a certain year. For
example, the municipal government decides to repair the sanitary sewer pipes which are in worse
condition, so the following pipes with condition index less than or equal to three are selected for
maintenance. Figure 10 shows visualization of pipes in worse condition at project-level.




                    Figure 10. Visualization of Pipes in Worse Condition at Project-Level

CONCLUSION
This research presents the advantage of GIS software in municipal asset management field. The result
exhibits the potential development about using GIS in municipal asset management in the future. The
conclusions are made regarding network-level integration, project-level integration and use of GIS in
municipal pipeline infrastructure management. The framework for network-level integration shows the GIS
software is a useful tool at decision-making process. It gives the municipal government suggestions about
the priority of asset which needs to be repaired. The project-level integration is followed network-level
integration and shows the disturbance from other assets. Municipal governments can be aware of the
potential disturbance before executing the maintenance

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3. Ghosh, J. GIS-An Intelligent Asset Management tool. National Local Government Engineering
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