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Two sides at loggerheads over
bridge lights
(The Post and Courier,
September 15, 2002)
BY ARLIE PORTER
Of The Post and Courier Staff
On a moonless August night, a few
hundred loggerhead sea turtle hatchlings popped out of the sand at Dewees
Island and scrambled off in the wrong direction - not to the sea, but
toward the glow of city lights above the
dunes.
A turtle was found dead the next
day, 300 yards down the beach.
Not having
found the safety of the ocean, the little, wayward sea turtle from Nest 10
marched instead into the heart of a growing debate over lighting the $650
million Cooper River bridge, now under construction in Charleston
Harbor.
Architects propose to aim searchlights
on the road deck upward, illuminating the bridge's 128 cables and nearly
60-story-high towers. This, they say, will create a virtual "Cathedral of
Light" visible from 30 miles away.
Charleston
architects who have reviewed bridge designs support this idea. The tower
and cables on a cable-stayed bridge give the bridge its shape and
elegance. To not light them at night would be crazy, they
say.
But this puts them at odds with
stargazers and turtle advocates, who say a lighted bridge will pollute the
night sky and disrupt a ritual millions of years
old.
Though the islands where turtles nest are
miles away from the bridge, and though the bridge lights may not outshine
the already bright glow over Charleston, the turtles and their vocal
advocates appear to have won the first round.
A S.C. Department of Transportation official said this week that the state
would consider turtles as the bridge lights are designed. Options -
including turning off ornamental lights during the six-month
turtle-nesting and hatching seasons - will be studied, a spokesman for the
bridge project said this week.
MOON
GLOW
After bubbling up out of the sand,
loggerhead hatchlings instinctively dash off toward the brightest light,
which until modern times has been the moon reflected on the ocean. The
evolutionary scramble is their only defense against marauding ghost crabs
and gulls.
Turtle volunteers say the new
bridge will add to the night glow above Charleston, Mount Pleasant and
North Charleston and further distract the endangered sea turtles from
their race to the sea.
"The brighter the city
becomes, the harder it is for the hatchlings to overcome that, even on
nights where there is a moon," said Sally Murphy, a S.C. Department of
Natural Resources biologist who specializes in sea
turtles.
It happened on Aug. 11, when
hatchlings from Nests 9 and 10 erupted from the sand at Dewees Island, a
barrier island east of the Isle of Palms. The next morning, turtle
volunteers could not find a single track that led to the ocean surf, said
Arla Jesson, the island's environmental-education
director.
In several places, the turtle tracks
ended at tracks left by ghost crabs. Those tracks led to crab holes in the
sand, Jesson said.
Because homes on the beach
that night were not lighted and there was no moon, the turtles had to have
been disoriented by the very noticeable glow over the cities to the west,
Jesson said.
"I strongly oppose this 'Virtual
Cathedral of Light,'" she said. "It will only contribute to the existing
light problem."
Besides hatchlings, the heavy,
awkward adult females are attracted to light. After laying eggs, they have
been known to lumber off toward lights on shore, according to Murphy. An
adult once wound up in a swimming pool on Hilton Head Island. Another,
after laying her eggs, was found swimming in a golf course pond at Fripp
Island.
LIGHTS
OUT
In Sarasota County, Fla., at the Cape
Canaveral Air Force Station at Port Canaveral, and over Brunswick, Ga.,
the skies are not as bright as they once were.
Having documented the effects of distant lights on turtles, biologists and
volunteers have argued effectively for darker
skies.
Lights on a bridge being built in
Sarasota County were turned downward so they could not be seen from the
beach. Lights at the Canaveral station, also visible from the beach, were
dimmed.
And in Brunswick, turtle advocates
were shocked by the brightness of lights on a new cable-stayed bridge,
which could be seen from the important turtle-nesting ground of Little
Cumberland Island.
The number of nests on the
island has declined from 249 in 1964 to 30 this year, according to Mark
Dodd, sea turtle coordinator for the Georgia Department of Natural
Resources.
Bowing under pressure from turtle
advocates, the state changed the lights over the roadway of the Sidney
Lanier Bridge from white to a more turtle-friendly
yellow.
The state transportation department
has yet to decide whether to turn off the bridge's decorative lighting
during the nesting season, Dodd said. "There are some people who want the
bridge lit up," he said.
As in Brunswick, the
number of nests in Charleston has declined sharply. Statewide, turtles
nests are down nearly 50 percent since 1980, according to
Murphy.
Murphy and loggerhead volunteers
acknowledge that lights from homes on the beach more easily lure sea
turtles than a distant glow over a city. But at 570 feet high, the towers
of the main span of the bridge will dwarf all other lighted structures in
the Charleston area and be clearly visible at night from the nesting
beaches at Folly Beach, Morris Island, Sullivan's Island and the Isle of
Palms, they say.
Turtles are not the only
creatures that will see these lights. Stargazers worry that the bridge
will whitewash the night sky.
Among them is
Charleston resident Edwin Gardner.
"In
Charleston we take pride in protecting our environment, but we're trashing
our biggest single natural resource - the night sky," Gardner said. "We're
losing our stars. We're losing the beauty of our
harbor."
State transportation officials have
touted the bridge as being the largest cable-stayed bridge in the nation
and say it is expected to stand 100 years.
But
to Jesson, the bridge has come to mean something else: "The bridge is seen
as a type of poster child for light pollution in
general."
HOW
BRIGHT?
When the bridge architects first
revealed their design, they proposed installing giant blue plastic lights
at the top of each of the two towers of the main span over the Cooper
River. These 56-foot-tall, 30-foot-wide rectangles at the top of the
60-story-high towers would have become the defining feature of the new
bridge, they said.
The state Department of
Transportation did not set aside money for any other decorative lighting,
meaning that cables and towers would not be
lighted.
However, Charleston architects never
cared much for the ultra-modern blue beacons. They said they looked like
Pez dispensers. Instead, they wanted the cables and towers lighted at
night to give the bridge form and beauty.
They
also challenged the yellow lights architects preferred, asking instead for
white lights to illuminate the cables sheathed in white
plastic.
The architects then returned with the
plan in which spotlights would be focused upward on cables and the towers
of the main span.
Up until now, the lighting
design has not taken into account sea turtles, said Charles Dwyer, bridge
project manager for the Department of
Transportation.
But that can change, he
said.
"We want to be responsible to the
environment," Dwyer said. "We're talking about an endangered species here
that has a right to live, and we should do what we can to not take away
the resources it needs to sustain itself."
Dwyer said that a number of alternatives can be considered on the bridge,
ranging from shielding lights, using turtle-friendly lights or turning off
ornamental lights during the turtle-nesting season, which runs from May to
October. For safety reasons, the road deck must be lighted, he
said.
In their presentation, lighting
designers said the spotlights are intended to light features of the
bridge, not empty out into the night sky.
"It
wastes energy if we're not lighting that which we want to light. We don't
want a lot of spillover," Dwyer said.
Dwyer
also said the bridge would not contribute significantly to the existing
nightly glow over the harbor. For instance, ballpark lights on both sides
of the harbor will be brighter, he said.
Charleston Mayor Joseph P. Riley Jr. and city architects said studies are
warranted to study the effect of lighting schemes on the
turtles.
Given the distance of the bridge from
turtle nests and the lighted night sky, it's difficult to believe the
bridge lights could disrupt turtles, said architect Sandy
Logan.
Logan said he doesn't want to appear
insensitive to "cuddly, squeezy things." But unless it's shown that the
bridge lights would disorient turtles, the lighting of the bridge should
take precedence, he said.
"If I had to come
down on one side or the other, I'm for the aesthetic concerns," Logan
said.
Dwyer, Riley and Logan, however, said
they are confident the bridge can be lighted without harm to the adult
loggerheads and hatchlings.
"I don't see why
it has to be lit brightly," Logan said. "It can be lit dim, like a ghost
schooner."
Riley described the currently
proposed lighting plan as gentle.
"Lighting
the bridge is very important, and we want to make sure that we have the
most beautiful bridge in the world," Riley said. "At the same time, it's
not as important as us to be responsible stewards for a species that is
millions of years old."
Arlie Porter covers
Charleston County. Contact him at porter@postandcourier.com or
937-5548. |