Outside waste had no ill effect on Watertown plant

The 35,000 gallons of flowback fluid treated in January at the Watertown wastewater treatment plant has little or negligible effects on the plant, said plant Supervisor Michael J. Silgar in a memo to the City Council.

Mr. Sligar is scheduled to give a complete report to the council at its meeting Monday night.

The city received permission from the state Department of Environmental Conservation in late December to accept the flowback fluid from the Ross No. 1 well in the town of Maryland. The vertical well operated by a Quebec-based company uses the controversial hydro-fracking process to extract natural gas from the Utica Shale rock formation.

“The sampling results presented in this report show that the loading indicated was not significant as compared with routine daily loadings at the sewage treatment plant and that the plant’s performances were not impacted in any manner by them,” Mr. Sligar wrote. “Further, the relevant conclusion of the toxicity testing is that no martalities or effects were noted in any of the treatments testes for either the vertebrate species or the invertebrate species.”

Environmental protection groups have said that large quantities of flowback fluid introduced in sewage treatment plants can kill the organisms that digest the waste. The groups have also stated that municipal treatment plants are not equipped to treat the fluid, which has a high salt content.