Agency says fireworks don’t hurt lake; more studies to be conducted
Water samples collected last year after fireworks exploded over Lake Tahoe showed a spike of a chemical called perchlorate.
The chemical can be harmful to humans if consumed in large amounts over a long period of time. But the levels of perchlorate detected are not likely to pose a health risk to people who get their drinking water from the lake, according to a report issued by the Lahontan Regional Water Quality Control Board.
Perchlorate, which contains chlorine and oxygen, is a main ingredient in black powder that helps create a controlled explosion in fireworks.
“We are seeing a level quite above drinking water standards right after fireworks, but we don’t anticipate water suppliers being able to detect it,” said Lauri Kemper, Lahontan division manager.
“In terms of us ever closing down the fireworks, it doesn’t appear necessary,” she added. “The results are showing very short-term impacts.”
Water samples to be tested this year will be collected by Pyrodigital Consultants, a company that launches the fireworks from a barge on Lake Tahoe.
“We often rely on self-monitoring,” said Lauri Kemper, division manager at Lahontan Regional Water Quality Control Board. “We’re anticipating the results to be similar to last year, so we have an idea what to expect. We’re hoping to get samples closer to the barge.”
Last year, Lahontan’s samples were collected about 600 feet from the barge. The level of perchlorate went from non-detectable before the display to 63 parts-per-billion after the show.
Dr. Glenn Miller, a scientist at the University of Nevada, Reno, collected samples 25 feet from the barge. He found perchlorate at 96 parts-per-billion after the display.
Lahontan sent copies of its findings concerning perchlorate to businesses that draw drinking water from the lake. The agency recommends water providers test for the chemical before and after the fireworks display.
“The question is, does it have a long-lasting effect?” said Bob Loding, operator of Lakeside Park Water Association, a company that draws from the lake not far from the fireworks barge.
“What this does is it alerts us that there is a possibility of a contaminant entering the system,” he said. “Even though we never have done perchlorate testing, we’ll do it this year to see if something turns up.”
Lahontan’s water testing came as a result of two complaints filed last year to the Tahoe Regional Planning Agency, one in the form of a letter from a Tahoe Meadows resident.
The second complaint was made by Edward Dilley Sr., a Zephyr Cove resident adamant about fireworks being harmful to the lake.
“It showed nothing,” Dilley said. “They took samples 200 yards out from the fireworks. The TRPA is turning its head to it (with) everyone saying nothing is going in. Besides all the chemicals they are throwing in there, it’s all this trash. That’s a joke. There is no clean-up effort. Three divers can’t get it all.”
Steve Teshara, executive director at Lake Tahoe Gaming Alliance, disagrees.
Casinos fund what is probably the best fireworks clean-up program in the country, Teshara said. This year, a modified pontoon boat will collect debris following the show.
“The first thing we do is scoop up any debris off the surface of the lake,” Teshara said. “The next day we come back with divers and retrieve any material that may have floated to the bottom. We also get beer cans, ski boots, whatever’s down there. That’s probably one of the cleanest bottom parts of the lake anywhere.”
Unexploded shells and pieces of cardboard and ski boots aside, algae growth spurred by the exploded fireworks was also an issue presented by Dilley.
Lake Tahoe’s famed clarity is due to its lack of nutrients, such as nitrogen and phosphorous. Scientists say nutrients getting into the lake feeds the growth of algae.
“There was some concern last year about elevated levels of nitrate but it really doesn’t appear to be the case,” said Larry Benoit, water quality program manager at TRPA. “We’ll see what future samples turn up.”
Tahoe Daily Tribune records indicate fireworks have been exploded over the lake for more than 25 years.
— Gregory Crofton can be reached at (530) 542-8045 or email@example.com