By Kathryn Reed
Public health is one of two reasons the Lahontan Regional Water Quality board on Wednesday voted to allow chemicals to be used to rid Lake Tahoe of invasive species – plant or animal. Public safety is the reason people who supply drinking water to thousands of people in the basin spoke against the decision.
Allowing pesticide use at Tahoe is practically revolutionary for the water board. The decision is a 180-degree turnaround from years of not allowing anything potentially harmful from being added to the pristine water.
Staff told the board that the long-term benefits of applying chemicals would outweigh any short-term degradation to the lake.
Tahoe Keys homeowners association is excited to be able to use herbicides to get rid of milfoil. Photo/TRPA
County vector control units have been using chemicals for years with Lahontan’s knowledge, but also in violation of its rules.
Vector control is also a health and safety issue.
Karen Bender with the El Dorado County Environmental Management Agency told Lake Tahoe News vector control rarely sprays in the Lake Tahoe Basin; it’s mostly larvae sites that are treated. She has volumes of records Lahontan could have checked at anytime. The board’s decision likely means Lahontan staff will be getting reports of all future chemical applications assuming pesticide use passes state and federal boards.
While water purveyors lost the battle to keep dangerous chemicals from the drinking supply of thousands, they did get the board to agree to notify all of them when an application will take place so all could comment on the proposed project.
There are 18 water purveyors around the lake, with 21 intakes between them. There are other water purveyors in the Lake Tahoe Basin, like South Tahoe Public Utility District, that use groundwater.
An issue for water purveyors is if the chemical is detected in the drinking water supply it must be mitigated. That can create problems downstream, so to speak. None of those concerns, though, were brought up at Wednesday’s meeting.
Nor was it discussed how one chemical might react with another.
In passing it was acknowledged the chemical to treat the problem could create problems for other aspects of the ecosystem. For instance if milfoil is eliminated, it could impact any species that uses it for habitat.
Besides public health, the other reason chemicals could be put into Lake Tahoe is for ecological preservation.
Three Tahoe Keys representatives spoke at the three-hour meeting at Embassy Suites on Dec. 7 – citing the need for chemicals to eradicate milfoil that is clogging the canals. The South Shore homeowners’ group years ago asked Lahontan for exemptions and was denied each time.
It may still be years before any herbicides are applied. This is because more boards need to approve the Pesticide Basin Plan Amendment. The final overseer to vote will be the federal EPA – maybe in July 2012.
An environmental impact report will need to be done by the Tahoe Keys Property Owners Association before Lahontan votes on that specific project.
All potential projects will undergo a rigorous vetting process, according to Lahontan staff.
“If the project qualifies, then the applicant takes their case to the board,” Mary Fiore-Wagner, Lahontan environmental scientist, told the board. “There will be robust monitoring, and tracking and recovery of species.”
All projects must also meet California Environmental Quality Act requirements.
One issue the board had some problems with was that chemicals under rare circumstances might be used without board approval. They understood emergency criteria – as in if the governor of California issues a mandate to do something. But what took some understanding was the “time sensitive” project that the executive director could approve on behalf of the board.
Staff explained “time-sensitive” could be the introduction of an invasive species to Lake Tahoe that would not reach the level of a state emergency. There are 36 species that have been identified as being a threat to Lake Tahoe, with 20 of them already in the water.
Another issue that changed from earlier versions of the amendment is chemical detection will be allowed to last for more than a week. This is based on how some chemicals are released.
Dan Sussman, Lahontan environmental scientist, said monitoring still must begin one week after the initial application of the chemical.
Any treatment could mean temporary prohibition of swimming, boating and fishing or other recreational activities.
Lauri Kemper, second in charge at Lahontan, after the meeting told Lake Tahoe News, that via CEQA, project applicants are supposed to document past, current and future projects that could impact theirs. Kemper said even if that does not take place, her agency would be aware of what is going on in Tahoe to know if application of one chemical could interfere/conflict with another.
While the decision by Lahontan affects the whole lake – because water moves – the agency only has oversight of California’s portion of the lake.
It is the Nevada Division of Environmental Protection that oversees what goes into Lake Tahoe in the Silver State. They follow requirements outlined by the National Pollutant Discharge Elimination System.
Bob Loding, water-wastewater specialist with Tri-state Water Operations in Zephyr Cove, told Lake Tahoe News that water purveyors are told by NDEP of anything going on with water – including being consulted before the rubber mats were put down to study the Asian clams.
He does not know of any time when chemicals have been allowed to be used in Lake Tahoe originating in Nevada.
Al Tinney, chief of water pollution control for NDEP, was not available for comment.
