“Engineering is the practice of safe and economic application of the scientific laws governing the forces and
materials of nature by means of organization, design, and construction, for the general benefit of mankind.”
—S.E. Lindsay, 1920
Gases
Electrons
Pipes transport fluids or gases, such
as water or natural gas. The primary
function of a pipe-based utility is to
transport product from point to point
without leakage. Pipes are constructed
of many different types of metallic and
nonmetallic materials.
An underground utility is a
network of pipes and cables
which transport one of the
following products:
1. Fluids
2. Gases
3. Electrons
4. Photons
A damaged underground pipe
or cable can produce a mere
inconvenience or the potential for
disaster. 6
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Cables transport electrons in order to
power the electrical grid. Transporting
electrons must be performed over cables
made of metal. Cables also transport
electrons to enable communication, such
as phone, video, or internet. The transport
of photons, or light energy, also enables
communication but can do so using cables
that contain no metal.
Fluids
At the point of damage, any leaking utility product
might represent a potential immediate hazard to
excavating personnel. The hazard may extend to
those responding to the damage or the general
public as well.
From a damage prevention standpoint,
there are only two possible outcomes
of any excavation activity:
1. No utility damage
2. Utility damage
Excavation damage causes leaks in pipes,
but what about cables? In the sense
that a leak is a diversion of product,
excavation damage causes leaks in cables
too. Excavation damage may result in
diminished service, the complete loss of
utility service, or result in an immediate
hazard to life or property.
For argument’s sake, let’s say 99% of all
excavations result in outcome #1. Why is the
percentage of excavations resulting in damage so
low? The use of a one-call system provides the
excavator with knowledge of where underground
utilities are located at the dig site.
Photons
The dig site is marked by locators responding to the
excavator’s use of the one-call system. The locators
use portable electromagnetic instruments to denote
the location of metallic underground utilities with
colored paint and flags; their instruments cannot
find nonmetallic lines. 7
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