The Gateway Arch has a new look, courtesy of a lighting system that is more energy-efficient and friendlier to water fowl.
The new, 1,200-watt LED lights switched on Tuesday use 60% less energy than the 7,000-watt xenon arc bulbs they replace. The new system also illuminates the monument more precisely, sending less light into the night sky, where it can be dangerously disorienting for birds traveling the Mississippi Flyway, a key migration route.
“It's pretty hard to light a stainless steel, curved object. So it's always been a challenge to try to figure out a lighting solution that would light it consistently and light it well. You’re shining light on something that’s basically a mirrored surface,” Gateway Arch National Park Superintendent Jeremy Sweat said.
The nonprofit Gateway Foundation, which has funded nighttime illumination of the monument since 2001, paid just under $1 million for the new system, a spokesperson said.
The most visible change for visitors will be the 30-second lighting sequence, which begins at ground level, with light traveling up each side of the Arch and uniting at its apex.
“The entire premise is that we’re bringing the two sides together to become one, when they join at the top. You can view that as east/west, you can view that as [bridging] people’s personal preferences. However you want to view it, we see it as a beacon that brings everyone together, and that makes St. Louis the gateway,” said Michael O’Keefe, chief operating officer of Technical Productions, the local company that designed and installed the new lighting system.
Wisconsin-based Electronic Theatre Controls designed the computer software that regulates the lights. The software assesses the Arch’s precise latitude and longitude in order to turn on the lights exactly 30 minutes after sunset, even as that time changes slightly every night. Currently, workers reprogram the start time for the lights about once a month. Reed Burkett Lighting Design focused the lights onto the Arch, with additional technology provided by Elation Lighting.
Gateway Arch officials also can adjust the color and temperature of the light, to make it less distracting to birds during periods of high migration. In 2002, officials began keeping the lights off for a few weeks a year during peak season for waterfowl traveling the Mississippi Flyway. This year the monument stayed dark for the full month of May, to account for shifting migratory patterns caused by climate change.
Lighting designers are working with scientists to determine if the new lights can safely stay on for more of the year. But in the meantime, they should pose less of a threat to birds when in use, said O’Keefe.
Nighttime illumination is an important factor in the public’s enjoyment of the Gateway Arch, Sweat said.
“They want to see that Arch lit up. They want to see it from downtown, they want to see it from the highways and interstates,” he said. “And so I think this is just going to enhance that experience that people love so much, of seeing that iconic monument lit up at night.”
Some of the old Arch lights will find new life in the collection at the City Museum.
Correction: An earlier version of this story misidentified the Gateway Foundation.
