Page 48 - McWane Poles Sales Manual 2024

48
McWane Poles, A Division of McWane Inc.
MARKETING BULLETINS
Ductile Iron Supports KEYS
in Hurricane Irma
Keys Energy Service used ductile iron
poles to storm harden its system, and the
utility did not lose a single one of them
when it was hit by Hurricane Irma – the
worst storm to hit the Keys in more than
fifty years.
After ten named storms and $28B in damage
in 2004 and 2005, the Florida Public Service
Commission (PSC) ruled that each public
utility must develop and implement an Electric
Infrastructure Storm Hardening plan, with a key
requirement to build to NESC Extreme Wind
Loading – Rule 250C.
For Keys Energy Service (KEYS), a board-
controlled public utility that provides electricity to
the lower Florida Keys, this new PSC Rule required
it to build to withstand 150 MPH wind. This strength
requirement prompted the utility to seek a pole
solution beyond its traditional wood poles.
Wood Pile Inspections
A second PSC Rule required utilities to inspect all
wood poles on their systems every eight years.
KEYS’ initial pole inspection in 2006 revealed that
3,000 poles or 27% of its system needed to be
replaced. To meet the new Storm Hardening Rule,
the utility replaced those poles with high strength
concrete poles.
The strength of concrete was sufficient, but the
significantly increased pole weight required KEYS
to buy larger line trucks. The use of concrete poles
led to lower installation productivity and increased
cost. Additionally, the poles showed stress cracks
and spalling. KEYS was concerned about the
longevity of concrete poles.
In preparation for its second wood pole inspection
and replacement project, the utility explored
options for an equally strong yet lighter alternative
to concrete. KEYS considered composite poles, but
ruled them out because of ultraviolet degradation
concerns and excessive deflection. After consulting
with other utilities, KEYS decided to pilot ductile
iron poles. The line crews found the ductile iron
poles much easier to work with than concrete, and
the utility realized a lower total installed cost. Dale
Finigan, the utility’s Director of Engineering, said,
“if we ever go back to concrete poles, I think the
line crew would resist.” KEYS’ second system-wide
inspection in 2014 yielded 470 poles or 4% of its
system for replacement. Instead of using concrete,
this time the utility used ductile iron to storm
harden the system.
Hurricane Irma
On September 10, 2017, KEYS endured a direct hit
from Irma, a category 4 hurricane. It was the worst
storm to hit the Florida Keys in more than fifty
years, with maximum sustained winds of 135 MPH.
The utility lost more than 625 poles and electricity
was cut off to the entire system.
Keys Energy Service installing a ductile iron pole
after Hurricane Irma