Understanding & Utilizing
The best asset a pipeline owner can have is the original alignment sheets or “as
built” document. This is basically a blueprint showing the exact route of the
pipeline and virtually all the knowledge that existed for that pipeline when built.
Almost always along the top of the sheet is a landowner’s name and a space
designating his ownership. On some documents it might indicate whether the
land is forest or in cultivation. Other typographical features might be listed as well
such as type of soil, hilly, rolling hills, wetlands, etc.
Generally along the middle section is a line or centerline of the actual pipeline on
a scale of whatever is indicated. There are stations along the way indicated
distance from the starting point to that “station”. These are important reference
points as there also will be various crossings marked off designating oil and gas
pipelines of varying sizes, water lines, sewer lines, underground cables, etc.
Sometimes there might be a more detailed explanation toward the last quarter of
the sheet. The more detailed section might show if there are additional lines in
the easement or corridor.
On the right hand side toward the bottom is sometimes a box that shows
maintenance records showing the nature of repair replacement work and the
date it was done.
More toward the bottom left there is usually a box that shows the description of
the actual pipe laid. The description will include outside diameter of the pipe,
grade, weight per foot and wall thickness as well as type of connection used to
join the individual lengths or joints of pipe.
Usually the description section will include an area showing the type of coating
on the pipe. This could be a tar and felt wrap with various designations such as
TGF-3 or a Fusion Bond Epoxy type coating.
Alignment sheets tell the story of the pipeline and they are an invaluable set of
documents for maintenance, recovery, or potential buyers.