DOE/EIS-0332; McNary-John Day Transmission Line Project Draft ...

2
2-6
Proposed Action and
Alternatives
Figure 2-3. Conductors, Ground
Wires, and Fiber Optic Cable
Tree Clearing
A fiberoptic cable would also
be strung on the towers below
the conductors (see Figure 2-3).
The fiberoptic cable would
have up to 72 fibers. The fiber
would be used for
communications as part of the
power system. Fiberoptics
technology uses light pulses
instead of radio or electrical
signals to transmit messages.
This communication system
can gather information about
the system (such as the
transmission lines in service
and the amount of power being
carried, meter reading at
interchange points, status of
equipment and alarms). The
fiberoptic cable allows voice
communications between
power dispatchers and line
maintenance crews and
provides instantaneous
commands that control the
power system operations.
Most of the vegetation along the corridor is low-growing sagebrush or fields that are
compatible with transmission lines. Tall trees cannot be allowed to grow under or near
the lines because electricity can arc, which can start a fire or injure or kill someone
nearby. The existing corridor does cross some windbreak trees, orchards, and tree farms
that grow deciduous trees for paper products. About 25 acres of trees would need to be
removed; a total of 50 acres would be permanently removed from cottonwood
production. Some trees may also need to be removed between the McNary Substation
and the river crossing.
BPA McNary-John Day Transmission Project
Draft EIS
February 2002