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Integrating Sanitary Sewer System Automation with GIS
Minhua Wang
Senior GIS Analyst
Geo Decisions,
A Division of Gannett Fleming, Inc.
209 Senate Avenue
Camp Hill, PA 17011
E-mail: mwang@gfnet.com
Minhua Wang
Senior GIS Analyst
Geo Decisions,
A Division of Gannett Fleming, Inc.
209 Senate Avenue
Camp Hill, PA 17011
E-mail: mwang@gfnet.com
Introduction
Sanitary sewer system automation is a computer system to automate sewer management activities involving management and maintenance of public sewer systems, handling complaints of sewer line problems and processing customer accounts and billings. There are many commercial software systems that handle sanitary sewer system automation. However, most of these software products do not have any GIS (mapping) fi.mctions, or only provide certain linkage to an external GIS software for displaying maps. In the other words, GIS is not an integral component in these software systems.
Integrating GIS into sanitary sewer system automation will include GIS as part of the sanitary sewer management system, not only at system function level, but also at database design level. In this paper, a comprehensive sanitary sewer maintenance/management system, known as “Municipal Sewer Management System”, will be presented. The system integrates GIS as an integral component and provides functionality for public sewer system maintenance, private sewer system investigation, sewer system modeling, customer complaints and accounts processes.
Data Model
A data model is a high-level logic design of data interaction between system components. Most sewer management systems include at least three domains: public system, private system and customer. From the database design point-of-view, these are considered as three objects. An object can have attributes or properties, and relationships exist between objects. Figure 1 illustrates the conceptual data model for a sewer management system. Since GIS is an integral part of the system, the spatial entity (e.g., sewer line, manhole) is included as a property of an object in the data model.
Figure 1: Municipal Sewer Management System – Data Model
The Customer object is the user of the sewer system. It has attributes such as house address, owner’s name, account number, etc. The Customer owns the private system and pays bills to the sewer authority for using the sewer lines and for any maintenance activities related to the private system.
The Private System object is the sewer line within a house or a building. It has attributes such as house address, sewer line that it connects to, and the spatial entity of building sewer. Since the private system connects to the public sewer line (Public System), the private system can contribute to problems in the public sewer lines.
The Public System object is the public sewer lines (including manholes and laterals) maintained by the sewer authority. It includes three spatial entities: sewer line, manhole and lateral. Each entity has its own attributes such as type, size, etc. The three entities are related geographically; for example, a sewer segment has an upstream manhole and a downstream manhole.
The data model illustrated in Figure 1 defines the system components and data flow within a sewer management system. The data model provides a logic basis for the system design, which will be discussed in next section. Based on the data model, a database for municipal sewer management system was developed. The database has two parts: a GIS database and a sewer management database. The GIS database is a file-based database with graphic elements, while the sewer management database is a relational database that contains sewer management related information. The linkage between GIS and sewer management database is provided through common fields such as line_id, mh_id, etc.
System Design
The primary function of an automated sewer management system is to provide users with tools for sewer data collection (such as inventory, inspection, etc.), data management (such as billing account management), maintenance planning, and management (such as job scheduling, work order generation, cost estimate, etc.). At the system design phase, a conceptual model of the system design which fi.mctions as building blocks for the system was defined; then the system functionality was determined based upon the municipal sewer management activity needs.
Conceptual Design
Figure 2 illustrates the conceptual model of system design. The Sewer Management/ Maintenance Activities Block provides the driving force for the system design. It incorporates business functions, such as inventory, inspection, rehabilitation, etc., into computerized functions. A management function menu system will be developed for this block. The Graphic User Interface (GUI) Block provides interfaces between management activities and databases. An example could be a command button or a menu item to initiate functions for TV inspection. The GIS Function Block provides embedded GIS functionality through Graphic User Interface. The Database Block supplies data for the system operations.
Figure 2: Conceptual Model of System Design
System Functionality
The system is developed for users at municipal sewer authorities or any sewer management organizations. Because of the diversity of users’ experience with computers and GIS, in particular, using Windows environment, all system functions were designed to be user-friendly. Based on the municipal sewer system business process, the system includes the following functionality:
GIS Functions
System Implementation
Database development is a critical task at implementation phase of the system development. As discussed above, the database is consisted of two components: a GIS database and a sewer management database. Therefore, the database development consists of two separate tasks: creating the GIS database and populating the sewer management database.
GIS Database: the system uses a particular GIS data format from a major GIS vendor. Creating the GIS database includes: 1) digitizing sewer system maps (sewer lines, manholes, laterals, building sewers, etc.); and 2) populating sewer system attributes based on pre-defined database structure, in particular, the identifiers for sewer lines, manholes and laterals, etc. If the sewer system maps are already in digital format (e.g., CADD drawings, other GIS data formats), the map files need to be converted to the GIS data format. Other GIS data, such as street centerline, orthophotograph, building footprints, etc., can be also incorporated into the database.
Sewer Management Database: in the prototype system, Access was used as the database server to manage the sewer management data. However, for system implementation, the database server can be any relational database management system (RDBMS) such as Oracle, SQL Server, etc. To populate the database, the user can either convert existing sewer data into the sewer management database or enter data using the data entry screen (GUI) provided by the system.
The system has been implemented in two municipal sewer authorities, one has existing data, and the other started from scratch. Since the system is developed using standard Windows
application development tools, all graphic user interfaces and programs can be customized to fit the user’s particular needs.
Conclusions
Sanitary sewer system automation provides useful tools for municipal sewer authorities to efficiently manage and maintain public sewer systems, handle complaints of sewer line problems and process customer accounts and billings. Integrating GIS into sanitary system automation greatly enhances the power for sewer system management by embedding GIS functions into a sewer management system. In addition, with GIS as an integral part of a sewer management system, the cost for purchasing a separate GIS software for the sewer management system is reduced. The system described above provides user-friendly graphic user interfaces (GUI), which allow non-GIS users to handle GIS functions with simple point-and-click. The system can be used for both office operation and field data collection. This system will greatly enhance the sewer system operations for municipal public works staff, sewer system managers and administrative professionals.
Sanitary sewer system automation is a computer system to automate sewer management activities involving management and maintenance of public sewer systems, handling complaints of sewer line problems and processing customer accounts and billings. There are many commercial software systems that handle sanitary sewer system automation. However, most of these software products do not have any GIS (mapping) fi.mctions, or only provide certain linkage to an external GIS software for displaying maps. In the other words, GIS is not an integral component in these software systems.
Integrating GIS into sanitary sewer system automation will include GIS as part of the sanitary sewer management system, not only at system function level, but also at database design level. In this paper, a comprehensive sanitary sewer maintenance/management system, known as “Municipal Sewer Management System”, will be presented. The system integrates GIS as an integral component and provides functionality for public sewer system maintenance, private sewer system investigation, sewer system modeling, customer complaints and accounts processes.
Data Model
A data model is a high-level logic design of data interaction between system components. Most sewer management systems include at least three domains: public system, private system and customer. From the database design point-of-view, these are considered as three objects. An object can have attributes or properties, and relationships exist between objects. Figure 1 illustrates the conceptual data model for a sewer management system. Since GIS is an integral part of the system, the spatial entity (e.g., sewer line, manhole) is included as a property of an object in the data model.
Figure 1: Municipal Sewer Management System – Data Model
The Customer object is the user of the sewer system. It has attributes such as house address, owner’s name, account number, etc. The Customer owns the private system and pays bills to the sewer authority for using the sewer lines and for any maintenance activities related to the private system.
The Private System object is the sewer line within a house or a building. It has attributes such as house address, sewer line that it connects to, and the spatial entity of building sewer. Since the private system connects to the public sewer line (Public System), the private system can contribute to problems in the public sewer lines.
The Public System object is the public sewer lines (including manholes and laterals) maintained by the sewer authority. It includes three spatial entities: sewer line, manhole and lateral. Each entity has its own attributes such as type, size, etc. The three entities are related geographically; for example, a sewer segment has an upstream manhole and a downstream manhole.
The data model illustrated in Figure 1 defines the system components and data flow within a sewer management system. The data model provides a logic basis for the system design, which will be discussed in next section. Based on the data model, a database for municipal sewer management system was developed. The database has two parts: a GIS database and a sewer management database. The GIS database is a file-based database with graphic elements, while the sewer management database is a relational database that contains sewer management related information. The linkage between GIS and sewer management database is provided through common fields such as line_id, mh_id, etc.
System Design
The primary function of an automated sewer management system is to provide users with tools for sewer data collection (such as inventory, inspection, etc.), data management (such as billing account management), maintenance planning, and management (such as job scheduling, work order generation, cost estimate, etc.). At the system design phase, a conceptual model of the system design which fi.mctions as building blocks for the system was defined; then the system functionality was determined based upon the municipal sewer management activity needs.
Conceptual Design
Figure 2 illustrates the conceptual model of system design. The Sewer Management/ Maintenance Activities Block provides the driving force for the system design. It incorporates business functions, such as inventory, inspection, rehabilitation, etc., into computerized functions. A management function menu system will be developed for this block. The Graphic User Interface (GUI) Block provides interfaces between management activities and databases. An example could be a command button or a menu item to initiate functions for TV inspection. The GIS Function Block provides embedded GIS functionality through Graphic User Interface. The Database Block supplies data for the system operations.
Figure 2: Conceptual Model of System Design
System Functionality
The system is developed for users at municipal sewer authorities or any sewer management organizations. Because of the diversity of users’ experience with computers and GIS, in particular, using Windows environment, all system functions were designed to be user-friendly. Based on the municipal sewer system business process, the system includes the following functionality:
GIS Functions
- Map manipulation: display sewer system map with different layers, zooming, labeling
- On-map identify: map tips, identify entity
- Red-line mark-up: add text, line, polygon, etc. on the map
- Spatial query: query database by drawing shapes on the map such as line, rectangle, circle, polygon, etc.
- Hyper-link map elements to pictures, sketched drawings, documents
- Print map
- Management function list: inventory, public system, private system, complaints, billing, modeling, report generation
- Activity menu for each function item
- Data collection for inventory
- Data collection for inspection
- Data collection for rehabilitation
- Data collection for maintenance
- Work order for inspection
- Work order for rehabilitation
- Account management
- Generic database management tools
- Phone logging
- System search
- Service request generation
- System query: both from the map and from the database
- Maintenance scheduling
- Mail automation
- Billing status checking
- Design conditions
- Design alternatives
- Overloading search and display
- Sewer system planning
- Customized report generation
System Implementation
Database development is a critical task at implementation phase of the system development. As discussed above, the database is consisted of two components: a GIS database and a sewer management database. Therefore, the database development consists of two separate tasks: creating the GIS database and populating the sewer management database.
GIS Database: the system uses a particular GIS data format from a major GIS vendor. Creating the GIS database includes: 1) digitizing sewer system maps (sewer lines, manholes, laterals, building sewers, etc.); and 2) populating sewer system attributes based on pre-defined database structure, in particular, the identifiers for sewer lines, manholes and laterals, etc. If the sewer system maps are already in digital format (e.g., CADD drawings, other GIS data formats), the map files need to be converted to the GIS data format. Other GIS data, such as street centerline, orthophotograph, building footprints, etc., can be also incorporated into the database.
Sewer Management Database: in the prototype system, Access was used as the database server to manage the sewer management data. However, for system implementation, the database server can be any relational database management system (RDBMS) such as Oracle, SQL Server, etc. To populate the database, the user can either convert existing sewer data into the sewer management database or enter data using the data entry screen (GUI) provided by the system.
The system has been implemented in two municipal sewer authorities, one has existing data, and the other started from scratch. Since the system is developed using standard Windows
application development tools, all graphic user interfaces and programs can be customized to fit the user’s particular needs.
Conclusions
Sanitary sewer system automation provides useful tools for municipal sewer authorities to efficiently manage and maintain public sewer systems, handle complaints of sewer line problems and process customer accounts and billings. Integrating GIS into sanitary system automation greatly enhances the power for sewer system management by embedding GIS functions into a sewer management system. In addition, with GIS as an integral part of a sewer management system, the cost for purchasing a separate GIS software for the sewer management system is reduced. The system described above provides user-friendly graphic user interfaces (GUI), which allow non-GIS users to handle GIS functions with simple point-and-click. The system can be used for both office operation and field data collection. This system will greatly enhance the sewer system operations for municipal public works staff, sewer system managers and administrative professionals.