Concerns over drinking water mean a program to kill a parasite in Lake Champlain is now in limbo.
The Vermont Department of Health says the LaPlatte River in Shelburne has never been treated before with the chemical that kills lamprey and it's concerned about the public water system. But the Vt. Department of Fish and Wildlife says the intake is in the bay, far enough away to be safe for people.
It's something no angler wants to see: lamprey are parasites feeding on bigger fish. Since 2002, the state has treated the rivers leading into Lake Champlain with a chemical called TFM which kills the lamprey. But this year, the state's health department is saying not so fast over concerns about the lampricide making it into drinking water.
"We think it is very unlikely that this would have an impact," Vt. Fish and Wildlife Commissioner Louis Porter said.
Porter says his department works closely with the federal government which runs the lamprey treatment program. He says the chemical would dissipate or break down before it made it to someone's faucet and he says the program has been very effective.
"We've seen lamprey wounding rates on lake trout and salmon go down quite a bit," Porter said.
He points to data showing that over the last decade, the number of wounded sport fish has been cut in half or more. And he says they also believe the program is helping the state's lake sturgeon, which are significantly affected by lamprey.
"We're very careful to not treat it above the minimum dosage needed for lamprey to avoid the possibility of killing other species," Porter said.
But that minimum dosage may be too much. The health department revised the standard for TFM from 35 parts per billion to 3 ppb following concerns about the original 1973 study on TFM.
"There just wasn't a lot of information in the study," State Toxicologist Sarah Vose said.
Vose says their new standard was set out of an abundance of caution until a new study is completed.
"It's not because of a certain study that shows that TFM is toxic. It's because we really don't know what the long-term effects of this pesticide are," she said.
With the new mandate in place, the federal government and state wildlife department are now working on solutions. They're hopeful they'll be able to find one in the next week or so, otherwise, their fall treatment may not happen and another generation of lamprey will make it to the lake.
"Whether we treat this year or not, that program will continue," Porter said.
There are a few possible solutions. One is to put in a new system that would act a lot like a Brita filter and use charcoal particles to filter out the chemical as it goes through the water system. Another might be to use less of the chemical if they can prove that would be effective against the lamprey.
PO Box 4508