A cost-effective GIS alternative for small pipeline operating companies

A cost-effective GIS alternative for small pipeline operating companies

Jane Heineman
Senior Engineering Assistant, PPL Interstate Energy Company
214 Shoemaker Rd, Pottstown, PA 19464
Telephone: 610-327-5343
Fax: (610) 327-5341
Email: jheineman@ppliec.com

John F. Dirkman, P.E.
Project Manager, James W. Sewall Company
147 Center St; P.O. Box 433
Old Town, Maine 04468
Telephone: 207-827-4456
Fax: 207-827-3641
Email: john.dirkman@jws.com

Abstract
Many smaller pipeline operating companies see the benefits of implementing a GIS to organize pipeline data, but cannot justify the cost of a large-scale AM/FM/GIS system. PPL Interstate Energy Company is a smaller pipeline company that worked with GIS firm James W. Sewall Company to implement a straightforward GIS solution that leverages existing technology investments. The presenters will discuss the process used to acquire landbase data, to organize existing pipeline data from a variety of paper-based and digital sources, and to integrate these data sets. We will also explore the functionality and benefits of the resultant geographic information system.

Company background

PPL interstate energy company
PPL Interstate Energy Company (PPL IEC) is a wholly owned subsidiary of PPL Corporation based in Allentown, Pennsylvania. The Interstate Energy Company pipeline was built in 1974 for the sole purpose of supplying economical fuel for electric power generation at power plants located in Pennsylvania and western New Jersey.

The pipeline transports No. 6 fuel oil, No. 2 fuel oil and natural gas to PPL’s Martins Creek Power Plant located on the western bank of the Delaware River. The 84-mile, 18-inch-diameter insulated pipeline starts at the Marcus Hook Pump Station adjacent to dock and storage facilities owned by Sun Oil Company, south of Philadelphia, and ends at the 1.9 million barrel oil storage terminal adjacent to the PPL Corporation power plant at Martins Creek, north of Easton, Pennsylvania.

Connected to PPL IEC’s 18” pipeline are the Gilbert Terminal and an 8” lateral pipeline which are owned by Reliant. The 380,000 barrel oil storage terminal is the receiving point for Reliant’s shipments of No. 2 fuel oil. The lateral runs east 10 miles from the terminal to Reliant’s generating station in Holland, New Jersey. PPL IEC operates and maintains the terminal and lateral under an agreement with Reliant.

Natural gas is delivered to the PPL Corporation power plant at Martins Creek. The 18” diameter pipeline is connected to Texas Eastern Transmission’s pipelines near Quakertown, Pennsylvania, and to Columbia Transmission’s pipeline near Bethlehem, Pennsylvania.

The administrative and maintenance center in Pottstown, Pennsylvania, is the headquarters for all operations and maintenance activity associated with the pipeline and terminals.

James W. Sewall company
James W. Sewall Company (Sewall), established in 1880, provides full-service pipeline mapping, data conversion, and application development services to the oil and gas pipeline industry. Services include aerial photography, surveying and GPS, aerial and close-range photogrammetry, GIS implementation, forestry, and engineering.

Prior data and methods

Data
For many years, PPL IEC has maintained alignment sheets in a CAD environment. These sheets contained landbase and pipeline data with enlarged aerial images acquired in the 1980s as backdrops.

In addition, PPL IEC maintained separate Microsoft Excel files containing bends and foreign crossings. Right-of-way data existed in a separate Microsoft Access database. As a result, updates required time-consuming manual changes to each affected alignment sheet area.

Typical PPL IEC alignment sheet
Methods
Because alignment sheets were manually drafted, they had no connection to the separate data files. Changes to these files had to be manually completed.

Current data and methods

Data
Alignment sheet pipeline and facility data now resides in a database connected to the CAD application. Pipeline data is contained in a master CAD file instead of individual alignment sheets.

Methods
Alignment sheet data maintenance is performed via the master CAD file and connected databases. Alignment sheets are generated on an as-needed basis.

Field data access is available through a variety of data viewing applications.

Pipeline asset data is available company-wide via the company Intranet.

Data acquisition and integration process

Data acquisition
Aerial Photography
Monochromatic aerial photography was acquired along PPL IEC’s pipeline route in April 2001. The route was flown 6000 feet above ground level, producing a photo scale of 1"=1000'. Flightlines were laid out prior to flying to ensure capture of a minimum corridor of 250 yards on either side of the centerline of the pipe.

For a portion of the pipeline, Sewall acquired monochromatic aerial photography at an altitude of 3960 feet above ground for 1”=660' (1:7,920) scale photography. This photography was used for mapping along proposed pipeline construction corridors.

Sewall used inertial measurement unit (IMU) and airborne GPS technology to provide high accuracy data for digital orthophoto production.

Ground Control
Sewall surveyors placed ground control targets and captured target coordinates in order to provide mapping that meets National Map Accuracy Standards (NMAS) and American Society of Photogrammetry and Remote Sensing (ASPRS) Class 1 accuracy standards, suitable for engineering-grade contour mapping. Control GPS technology was used to acquire control point coordinates.

Pipeline locating
PPL IEC field crews used GPS units to capture coordinates of above-ground pipeline features. These features included valve stems, casing vents, and road crossings. PPL IEC provided this data to Sewall in ASCII file format for Sewall’s integration with other pipeline data sources. The Pennsylvania South State Plane coordinate system was selected due to the area covered by the PPL pipeline and the opportunities for direct integration of data from local, state, and federal agencies.

Digital orthophoto production
Sewall first scanned the film to a 1' pixel. After producing the digital terrain model on softcopy workstations, Sewall produced the digital orthophotos from the digital terrain model, scanned imagery, photocenter data, and the camera calibration report. Digital orthophotos were then written to CD-ROM in a TIF/TFW format.

Limited planimetric mapping
Sewall provided limited planimetric mapping consisting of roads and bridges, rivers and streams, and railroads. Vector mapping was captured to 250 yards on either side of the pipeline at a 1"=200' mapping scale. For the areas photographed at 1"=660'photo scale, Sewall produced 2-foot contour topographic mapping. This contour data will be used for planning, engineering, and construction for new proposed pipelines.

Data Integration
Sewall first merged and spliced the existing CAD alignment sheets to form a continuous pipeline file. Next, the pipeline was geopostioned and adjusted based on field-collected GPS data. Sewall then captured pipeline objects and object attribute data using data collection tools. Captured objects included:

Sewall worked with PPL IEC to resolve apparent data conflicts that emerged during the data integration process. Identified possible data conflicts were highlighted and transmitted to PPL IEC. After receiving the conflict resolution , Sewall made the appropriate changes to the CAD/database data.

Since prior alignment sheets had ROW data and annotations placed according to the enlarged aerial images, Sewall warped this data to conform to the new digital orthophoto images.

In order to efficiently place images as backdrops in the new alignment sheet map windows, Sewall cropped the TIF/TFW images along the placed alignment sheet boundaries. Because PPL IEC’s field crews expect to find pipeline data on certain alignment sheets, the alignment sheet boundaries were locked, preventing typical system users from repositioning them.

During the data conversion process, a variety of manual and automated processes were used to provide quality control on the converted data. Also, Sewall built data validation rules to check converted data at the time it was entered into the system. The data validation rules provided conversion technicians with an instant feedback mechanism during data conversion.

Database configuration
Sewall’s integrated system is built around pipeline objects with known characteristics and behaviors. PPL IEC can use Sewall’s Object Editor to configure database tables for pipeline objects, fields, and values. Database forms are built on-the-fly from database values with no reprogramming required.

Alignment Sheet Generator Configuration
Sewall edited alignment sheet configuration files to provide alignment sheets that closely matched PPL IEC’s existing alignment sheet layout. PPL IEC’s alignment sheets consist of a ROW/Field Note Band, Map Window, Material Band, Property Owner Table, Ell and Horizontal Field Bend Table, Revision Block and Title Block.

Installation and training
Sewall provided a technical support person for one week at PPL IEC’s office in Pottstown. During this time, Sewall installed the required applications and provided training in the operation of the connected system.

Benefits
This GIS implementation provided PPL IEC with the following benefits:

1. Current and accurate pipeline and landbase data
One immediate benefit of the project was the acquisition of current and accurate pipeline geoposition and landbase data. Field crews, familiar with the operation of GPS units, can readily locate points along the pipeline. More current and accurate landbase data allows better emergency response and pipeline expansion planning.

2. Integrated and organized data
Having integrated CAD and database data makes pipeline data maintenance more efficient. Changes are made in one place and shown via a variety of reports including alignment sheets. Multiple users can access the data simultaneously, with edits handled through dynamic record locking.

3. Current CAD environment utilized
PPL IEC’s new integrated system uses the same CAD environment as the company's previous system. PPL IEC is not required to learn a new CAD system, allowing the system users to use the connected system immediately, avoiding expensive retraining costs.

4. Current alignment sheets
Because alignment sheets are now a report from the integrated system, PPL IEC can generate and publish new alignment sheets on an as-needed basis. Alignment sheets can be plotted or transmitted via the company Intranet.

5. Current pipeline reports
Similarly, a variety of reports can be run at any time. Reports are user-configurable, allowing anyone with sufficient access credentials to build and generate reports containing pipeline data.

6. Reduced alignment sheet maintenance effort
Based on Sewall’s experience with similar clients, the estimated time savings of maintaining alignment sheets in a connected CAD/database system with an automated alignment sheet generation application is approximately 40 percent over the traditional, manual CAD-only process.

7. Integration of external datasets
Since the pipeline system is now placed as a unified, geopositioned CAD file, vector data can be overlaid with existing pipeline and landbase data. A variety of local, state, and federal agencies make available property owner, environmental, transportation, soil type, and land use data. Similarly, external databases with geopositioned records can be imported or linked and viewed in the CAD environment. Specifically for pipeline companies, integrated data can include corrosion data from in-line inspection tools or bell hole inspections.

8. Publishing of pipeline data to XML or SVG formats for web-based viewing
Pipeline data can be expressed in an Extensible Markup Language (XML) or Scalable Vector Graphic (SVG) format. These output files can be stored on an Internet server and viewed via commercially available Internet browser plug-ins.

9. Corporate and field data access
Because pipeline data is stored in a database, corporate users can access, view, edit, and generate reports of pipeline data via the company Intranet. Similarly, data can be published and distributed for disconnected field data viewing and editing. Field crews can use either portable computers or handheld units with attached GPS units.

10. COM-based system
Since Sewall’s integrated system is based on Microsoft COM/ActiveX architecture, a variety of benefits are realized. The application is built from multiple COM components. These components can be individually enhanced and replaced without impacting other components. Also, should PPL IEC choose to change CAD or database applications, only the components that interface directly with these systems would require replacement. Sewall’s use of ActiveX controls allows pipeline object controls and forms to be accessed by users via standard Internet browsers.

11. User alignment sheet format configuration
System users are free to reconfigure existing alignment sheet format configuration files or to create new files. This capability allows users to add or remove data bands and change the type or appearance of data within individual bands.

12. Open pipeline data model
Since the pipeline database is an open data model, users can add, remove, or change pipeline objects including valves, tees, coatings, and casings and their typical attributes without programming or data model changes. Forms are designed to auto-configure on the fly in accordance with the pipeline object’s characteristics. This technology is a great improvement over traditional systems that require reprogramming whenever data model changes are necessary.

Summary
Currently in use, this GIS implementation has proven a practical, cost-effective solution to PPL IEC's pipeline data needs. Utilizing existing CAD applications, this system can serve as a model for other smaller pipeline companies who require GIS functionality at lower cost.