Engineering the GIS way

Over the past couple of years, this editor has addressed the use of Geographic Information System (GIS) technology to help develop pipeline system concepts and provide for mapping information and design criteria to solicit reliable bid pricing without extensive ground surveys especially in remote regions. Various applications have been addressed for developing hydraulic simulation models, assess terrain concerns, quantify obstacles such as road and water or utility crossings and other infrastructure impacts to pipeline construction, and right of way planning. We have described proven applications that have been successful for use in developing large oilfield developments and cross country pipeline transmission systems.

Pipeline GIS applications vary among individual operators for using the technology to track or analyze right of way records, tax assessment information, risk and reliability evaluations, corrosion control, regulatory affairs, maintenance and inspection, flow models, emergency response planning, weather and market demand loadings, environmental compliance, GPS inventory surveys, and a myriad other applications that allow the operator to improve efficiency and effectiveness in the management of their systems.

Previous columns have focused on the use of GIS by owners, engineering firms, and contractors to develop design concepts through Front End Engineering Design (FEED), preparation of bid packages, development of contract documentation, and construction planning and scheduling. The goal here is to address important issues in applying GIS while considering conventional requirements for measuring progress and documenting owner acceptance in project engineering and contract management.

Conventional project engineering progress is based upon document type deliverables such as design calculations, reports, specifications, requisitions, test packages, and drawing production. Man-hours and milestones can be assessed to determine productivity and confirm billings and progress as the project develops over time. Development of a database such as a GIS is somewhat different.

There needs to be a change in culture for pipeline engineering firms to succeed in the future. No longer should man-hour estimates based upon drawings and document deliverables be the key to executing projects. With GIS, you really develop a database. Alignment sheets are generated automatically from the database. A typical drawing is almost obsolete. The details of the drawing can become objects in the database. The Engineer can then arrange those objects into a “design.” This is much the same way that AutoCAD employs database principles for creating a computer aided drawing.

Milestones can still be developed for a GIS-based project. Reports that establish criteria for developing the database and form the design basis for the pipeline project can also be documented for progress status. There will always be ground validation of critical positions and survey control that can establish a milestone. Development of shape files for pipeline objects and typical design criteria for multiple applications can also be standardized for GIS applications to establish additional deliverables.

Construction of the database is very different from the conventional means of developing a series of drawings or alignments sheets in a GIS environment. With drawings, experience has established an estimating basis for creating and advancing drawing status over a project from initial route selection through survey alignment, permitting, design, and construction issues. With the GIS database, the same stages are progressed as the information develops and the project advances but assessment of progress is not as clearly measured. Alignment sheet generation of the database can be used to gauge progress but more creative means of establishing status should be developed between the engineer and the client.

Database construction for pipeline design can include map-base information, pipe specification information, design criteria, survey data, imagery, wetland boundaries, high consequence areas, and database tools such as digital elevation models, land data, environmental data, census data, soils data, and other public and private domain information resources. By converting from a conventional project engineering mode to a GIS-based pipeline project, there will be a substantial increase in productivity and efficiency.