Anybody who has ever seen the stunning coloration of Yellowstone’s Grand Prismatic Spring could easily argue that the hot spring is one of the most beautiful natural sites on Earth.
Located in the Midway Geyser Basin a few miles north of Old Faithful, Grand Prismatic Spring’s stunning rainbow-like dispersion of colors has made the United States’ largest hot spring a favorite destination for visitors and nature photographers the world over.
But the best views of Grand Prismatic Spring are from above, where the pool’s rich turquoise waters contrast with the stark, copper-colored land surrounding the spring.
On Aug. 2, 2014, one Yellowstone tourist from the Netherlands, Theodorus Van Vliet, tried to get a eagle’s eye view of the spring with the use of a remote-controlled flying drone. But instead of getting the photograph of a lifetime, the drone instead crashed into Grand Prismatic Spring’s waters.
Though it’s been almost 11 months since the incident, Yellowstone officials have not been able to locate the drone.
A similar fate to Minute Geyser?
Yellowstone National Park geologist Henry Heasler said when officials were first notified of the crashed drone, there was a fear of how it could impact Grand Prismatic’s thermal features.
“We had a lot of questions,” he said. “How big was the drone? Did it leave an impact crater? How big was the battery pack and could the pack affect the chemical levels in the water? Was there anything that could affect flow patterns?”
Scientists were particularly fearful that the sunken drone could clog one of Grand Prismatic’s vents or melt and permanently disrupt the bacteria in the site’s microbial mats, which produce the brilliant colors that have made the spring one of the park’s most popular attractions.
Heasler said that the vast majority of tourists who visit Yellowstone are extremely respectful and conscientious about preserving the park’s unique geothermal features.
But that hasn’t always been the case.
Minute Geyser in the Norris Geyser Basin is a well-known example of how thoughtless human behavior can permanently damage one of Yellowstone’s geothermal sites.
Minute Geyser was named because it once erupted every 60 seconds. However, early visitors to the park threw rocks into the geyser’s larger vent. Now, the eruptions are irregular and usually originate from the geyser’s smaller vent, rarely reaching the 50-foot heights it was once known for.
Even today, park officials have to occasionally deal with reckless visitors throwing objects like rocks and coins into some of the geyser pools.
“One penny might not hurt a lot, but once you get a hundred, you could clog the spring,” Heasler said.
Heasler recalls an incident when a visitor threw a handkerchief into a geyser, only to have it tossed back out, perfectly cleaned by the boiling hot waters.
Needle in a haystack
Park officials faced unique challenges when they tried to recover the downed drone shortly after it crashed last August.
Though there were witnesses to the incident, there was no consensus over where the crashed drone was actually located in the water.
“It was like looking for a needle in a haystack,” Heasler said. “For perspective, the spring is 300 feet in diameter and 160 feet deep, with an estimated 3 million cubic feet of water. The drone was roughly 1 cubic foot in size. One cubic foot is a small percentage of the total volume of the pool.”
Heasler said there were numerous considerations made in the planning of the recovery operations. A proposed idea was to use a small radio-controlled submarine to search Grand Prismatic’s waters for the drone.
But this idea was scrapped because it was considered too invasive to the hot springs, particularly if the submarine malfunctioned and sunk, potentially causing additional damage to the waters.
Plus, the spring’s sulfuric waters can range in temperature from 160 to 200 degrees Fahrenheit, which makes the environment extremely difficult to work in.
Eventually, officials decided the safest and least invasive way to locate the drone was through extensive visual observation.
Helicopter flyovers were utilized, taking photographic and video images that were closely monitored for evidence of the crashed drone. Naturally, park officials made certain that the helicopters were far enough away from Grand Prismatic in case of another crash.
Officials also used high-powered binoculars observing from nearby vantage points, such as the Firehole River, to search Grand Prismatic’s waters.
But in the end, the search for the elusive drone came up empty.
On a hot afternoon last week, the parking lot to Grand Prismatic Spring was full, so hundreds of visitors had to park their cars alongside the shoulder of nearby Grand Loop Road. During the summer months, when park visitation is at its peak, this is not an uncommon sight.
Though the crashed drone is still missing in action, the vivid colors at Grand Prismatic Spring are still as strong as ever. As visitors walk along the hot pools on the wooden boardwalks, that distinctive sulfuric smell permeates the air as clouds of steam rise from the waters and are pushed away by the wind.
Some of the visitors openly discuss their fears that the crashed drone will eventually damage the hot spring forever.
But Heasler said that after 11 months of close observation of both the chemical and physical composition of Grand Prismatic Spring, geologists have good news to report.
“It was a sad search to be involved with,” he said. “We used many techniques, but in the end, we couldn’t find the drone. But the good news is that we have not noticed any measurable changes in Grand Prismatic Spring.”
Heasley also said that by now there’s a low probability that the drone will emerge, though it could someday float to the top. It’s been down there long enough that the microbes in the water may have already consumed it, he said.
But in the foreseeable future, park geologists will continue to closely monitor Grand Prismatic for any changes.
In June 2014, two months before the crash at Grand Prismatic, the National Park Service banned the use of private drone usage within national park lands. Unfortuantely, Van Vliet was not the only Yellowstone visitor last summer to violate the order.
One month after the ban was implemented, a German tourist named Andreas Meissner crashed a drone into Yellowstone Lake near the West Thumb Marina. He was banned from Yellowstone for a year and fined more than $1,500.
A few weeks after the incident at Grand Prismatic, Donald Criswell of Oregon was caught flying a drone over the Midway Geyser Basin, where Grand Prismatic is located. In October, he was ordered to pay $1,000 in fines.
As for Van Vliet, the Dutch tourist was ordered by a U.S. federal judge to pay $1,000 in fines and $2,200 in restitution for the mishap with his drone.