New Construction Methodologies using GIS, GPS, and the Web
The Benefits
The benefit of this approach is the ability to build an accurate model of the real world and place
the pipeline into that model. As adjustments are made, ties to physical features may be measured
using photogrammetric techniques rather than re-surveying the same feature as it relates to the
centerline. The continuous databases built throughout the project are delivered in a GIS format,
eliminating the cost to convert manual records when a GIS is implemented. The following
describes further benefits:
- The initial photo mission is flown, controlled by GPS survey, and the images are ortho
corrected. Ortho corrected imagery is compiled by a digital process that corrects the image to
horizontal scale. This means that all of the compiled digital data is shown on the photo
image at correct scale and in its proper position. Digital data remains intact to scale for
future plotting. It is not altered to fit a rectified image or digital drawing of imperfect scale.
Using only rectified imagery, each route adjustment and each additional feature displayed on
the photo would have to be manually adjusted to fit the photo image, taking additional time.
- This same ortho is used for FERC filings, construction alignment sheets, site-specific
drawings, ROW plats, permit drawings, route refinement, environmental permits, and as a
base for a future AM/FM-GIS.
- The centerline is refined using this methodology with limited access to private property. The
engineers also have access to technology, capabilities, and additional data not available from
viewing hard copy map sheets.
- As-built surveys in the field are expedited, since the physical features around the pipeline
have already been mapped. Only the centerline needs to be modified and new attributes
added. The final alignment sheets are generated from the continuous file using software,
rather than drafting all new sheets in CAD. The attribute data is also available for other
applications and queries.
- Both graphic and a facility databases are included in the final delivery. Hardcopy alignment
sheets will also be delivered. These databases can be loaded directly into a GIS, eliminating
the cost to convert data into a GIS.
- This methodology has been proven over the last 3 years on over 15 major pipeline
construction projects.
The benefits of GIS are another topic altogether. The benefits of the technology are proven and
the cost of hardware and software has been dramatically reduced. Many companies have
implemented a variety of databases and GIS solutions to maintain their facilities—ROW,
environmental, operational data, etc. Pipeline operators are using these systems for DOT
reporting, pipeline integrity, and analysis of corrosion and smart pigging data. Moving to GIS is
the next step in pipeline industry evolution, just as CAD was to manual mapping. However, the
benefits of GIS are even greater now that positional references and bases maps are being created
and maintained in a digital world.
Summary
To really get the full benefit of this technology and create the desired savings, you must integrate
and change the field collection of data and how pipelines are engineered. On this front, Willbros
Engineers has been forward in their approach to pipeline projects and automated many of their
processes. M.J. Harden and Willbros have signed a Strategic Alliance to bring automation and
web technologies to pipeline projects from start to finish. This has provided pipeline companies
with increased access to project information through the web, reduced the project timelines for
all phases of the project, and reduced project costs. With these kind of benefits, why do a project
any other way?
