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Enterprise GIS - Building a Strong Foundation
Teri Boudreau Landrum
City of Grapevine
200 S Main Street
Grapevine, Texas 76051
What is Enterprise GIS?Teri Boudreau Landrum
City of Grapevine
200 S Main Street
Grapevine, Texas 76051
According to The American Heritage Dictionary of the English Language, Third Edition, an Enterprise is defined as 1) an undertaking, especially one of some scope, complication and risk 2) a business organization. The term Enterprise GIS is loosely defined in the GIS community as a GIS that provides an organization with desktop access to GIS data and information. Neither definition encompasses the full meaning of Enterprise GIS although both are quite true.
An Enterprise GIS is –
- a GIS that integrates geographic data across multiple departments and serves the entire organization
- a GIS that provides access to other information systems in the organization by using a map or application as the integrator of the organization’s information
- a GIS that provides desktop access to all users
- a GIS that supports applications that are easy to use and understand
- a GIS that is well-organized and well-managed
- a GIS that is supported by all departments and management
In April of 1999, the City of Grapevine received a government grant that provided the City with the core GIS software they would need to start building a GIS. A few months later, the City, headed by Information Technology, contracted the services of IT Nexus, Inc. to create a GIS System Development Plan. This plan included a Needs Assessment, GIS System Concept Plan and an Implementation Action Plan. It was recommended to the City that they hire a GIS Project Manager and a GIS System Administrator. The City chose to contract the GIS Project Manager through IT Nexus, Inc. It was determined that the GIS Project Manager and the existing Information Technology staff could share the duties of the System Administrator.
Needs Assessment and System Concept Plan
A Needs Assessment is performed to take inventory of the City’s existing resources and current work functions. The existing mapping system at the City of Grapevine was housed in the Public Works department. The graphic data files were unorganized, redundant and inaccessible by other departments. Most departments had to rely on Public Works to make their maps and provide them with graphic information. In addition, the AutoCAD data contained very little attribute information and could not be linked to any external databases. The only tool that was available for viewing and editing the data was AutoCAD.
Since a large portion of the City’s graphic data investment existed in the form of AutoCAD files, it was recommended that the City convert the files to a format that the GIS software could manage and maintain. After the GIS graphic files are built, a relationship between existing systems/databases could be established and new attribute data could be added to the SQL Server relational database. Additional GIS data requirements were determined by finding out what types of applications were most important to the City. A conceptual database design was created to show the relationship between the GIS graphic data, the attribute data stored in SQL Server and the external databases and systems. It was found that the City’s existing computing environment could support an Enterprise GIS if a phased process of upgrading hardware, software and network components was implemented as the project progressed. It was determined from the Needs Assessment that the City of Grapevine would benefit greatly from an Enterprise GIS. Some benefits would include increased work efficiency, better service to customers, improved maintenance planning and enhanced analysis.
Implementation Action Plan
The Implementation Action Plan takes a three-phase approach to building and developing an Enterprise GIS. In order to successfully implement an Enterprise GIS, four essential elements must be in place: Data, Software/Hardware, Applications and People. All are key to the success of the project. The implementation plan takes all four of these elements into account in each phase. At the end of each phase, the City will have approximately one third of its data requirements, a quality control program, four to six priority applications, support staff and the software and hardware necessary to support it. The Implementation Plan also contains a planning level budget estimate for completing the implementation of the City’s Enterprise GIS. The cost estimate was broken down into tasks for each phase of the project.
Status of Phase One
In addition to converting the existing AutoCAD files in Phase One, data was acquired from external agencies such as the Appraisal District, the E-911 District and the Council of Governments. The Appraisal District parcel data required graphic conversion and, in over half the city, redrawing of the linework. Street Centerlines with address ranges for approximately two-thirds of the city were obtained from the E-911 District. Political boundaries and orthophotography were obtained from the Council of Governments. The GIS Data Server, the Intranet/Internet Server, GIS related software and the Relational Database Management System were acquired and currently functioning.
Two administrative groups were formed at the City of Grapevine to oversee the project and provide support and feedback to the GIS Project Manager. The Steering Committee consists of City Managers and Department Directors. The GIS User Group is comprised of representatives from all city departments and most divisions. Temporary and part-time staff was acquired to fulfill the City’s staff support obligation. They performed the functions of data entry, data compilation, research and verification.
The first enterprise application was a browser-based Intranet application called Citywide Ad-Hoc Query. It allows the user to find a location by entering an address, intersection or by querying the tax roll information. Once a location is found, the user can query other data layers, view the orthophotos, create buffers, measure, make a map, etc. Since City staff was already familiar with using an Internet browser, the learning curve was greatly reduced.
Database Design
The database design is the foundation for building an Enterprise GIS. It must be thorough, well-documented, permit modifications and allow continual updates. Many Enterprise GIS efforts suffer from either the complete lack of a database design or one that is so rigid that it can not grow as the organization grows. The database design must support all business functions and provide a means for data integration with external data systems. The design should provide outcome guidelines for data conversion. For example, if the design provides for the linking of tax roll information to the parcel graphics, the conversion must involve populating the parcel polygons with a unique identification number that will link it to a record in the tax roll.
Before any attribute data was collected, converted, acquired or researched, the City had to determine what the City wanted from their Enterprise GIS and what type of data they needed it to manage. IT Nexus initiated the process by conducting a weeklong database design workshop. The design process was divided into subsections based on the GIS data model e.g. Environmental, Parks, Property, Water, Storm. Sample database templates were used to guide the participants through the inquiry process. In most cases, the participants were given assignments to gather more information for the consultants. The purpose of the workshop was to gather enough information to create a custom database design that specifically addressed the needs of the City of Grapevine.
The database design consists of fourteen subsections. Each subsection should have the following data components defined:
- GIS graphic content, structure and format
- SQL Server attribute data content, structure, format and constraints
- Relationships between graphic features and attribute data
- Relationships between attribute data tables
- Data dictionary definitions of graphic features and attribute data
Park Trail Facilities
The Trail Facilities coverage contains points that represent the location of facilities located along the trails in the City of Grapevine parks.
| Coverage Name: | Trailfac |
| Feature Class: | Point |
| Coverage Type: | Point |
| Update Frequency: | Low |
| Aliases: | None |
| Data Sources: | Grapevine paper maps |
| Grapevine Park Master Plan | |
| Grapevine Park Playbook |
Park Trail Facilities Tralifac
Info tables
| Trailfac.Pat | |||
| Item | Format | Null | Item Definition |
| Area | 8,12,F,3 | NA | Inapplicable for point, set to zero |
| Perimeter | 8,12,F,3 | NA | Inapplicable for point, set to zero |
| Trailfac# | 4,5,B | NA | Internal sequence number, generated by A/I. |
| Trailfac-ID | 4,5,B | NA | Internal point ID – do not use as primary key for SQL Server data tables. |
| Trfac_UID | 8,8,C | No | User-defined, unique identifier for each point. Serves as a link to SQL Server data tables. Ex. TRFAC001 |
| Type | 2,2,C | No | Type of park facilities – see D_TRLFAC |
| Last_User | 3,3,C | No | Last user to update coverage |
| Last_Date | 10,10,D | No | Date of last update to coverage |
| Last_Time | 4,4,I | No | Time of last update to coverage |
SQL Server tables
| Trailfac | |||||
| Name | Type | Null | Constraints | Definition | Notes |
| Trfac_UID | Char(8) | No | Primary Key | Unique identifier | Ex. TRFAC001 |
| Trail_UID | Char(7) | No | Foreign Key | Trail along which facility is located | Ref: Trail |
| Trfac_Type | Char(2) | No | Foreign Key | Type of trail facility | D_Trlfac |
| Trfac_Name | Varchar(35) | Yes | Name of trail facility | ||
| Last_User | Char(3) | No | Last user to update record | System generated | |
| Last_Date | Datetime | No | Date of last update to record | System generated | |
Domain tables
| D_Trlfac | ||||
| Name | Type | Null | Constraints | Definnition |
| Trfac_Type | Char(2) | No | Primary Key | Type of park facility |
| Trfac_Desc | Varchar(25) | No | Description of park facility | |
| Last_User | Char(3) | No | Last user to update list | |
| Last_Date | Datetime | No | Date of last update to list | |
| Trail Facility Type Domain List | |
| Trfac_Type | Trfac_Desc |
| BN | BENCH |
| DF | Drinking Fountain |
| HM | Historical Marker/Museum |
| IS | Information Stop |
| RR | Restrooms |
| TH | Trail Head |
| TR | Trash Receptacle |
Information stops include kiosks and points of interest. | |
Entity Relationship Diagram
A very useful tool for demonstrating the relationships within a database design is the Entity Relationship Diagram (ERD.) It is a charting tool that allows the relationships between data elements to be examined more easily. The following illustration is the ERD for the Parks and Recreation subsection.
Issues
Most projects, including those that are well managed and thoroughly planned, have their share of problems and issues. Many of the issues that were discovered at Grapevine were a result of incorrect or incomplete data. The City assumed the data they were providing IT Nexus was correct and complete. Research and more interviewing had to be performed in order to obtain the correct data. In some cases, data that was originally thought to be available could not be found. In the case of the Appraisal District, the City was told that they would be provided with ready-to-use GIS data. When the actual data was received, it required over 200 hours of additional work.
Since the City has formed agreements to maintain and share data with many of the external agencies, the data is becoming more accurate and easier to maintain. The City opted to adopt the E-911 database design for street centerlines to facilitate the update and sharing of GIS data. This agreement has fostered procedural changes throughout the City. These changes have required departments to communicate with one another and work together.
Many of the data systems in the City are being replaced with newer, better systems. Since the database design did not try to replicate the way that those systems store data, the only major change that was involved was modifying the unique identifier. The application will provide the link between the GIS and the system and provide the interface to query the system’s data.
Conclusion
Implementing an Enterprise GIS is a challenge. Cooperation, planning, project management, knowledge, funding and time are all extremely important factors. Building a strong foundation that can support the GIS through its development and into its maturity is vital for the success of the project. This paper discussed the methods for building the foundation and the complexities of implementing an Enterprise GIS that will support the needs of all the primary work functions of a city government.