Amador County – Jackson City Council heard a report last week from a consultant who said some alternatives for a sewer plant may not be economically feasible, but the city may still be able to get a permit to discharge year-round into Jackson Creek.

Tom Grovhoug, president of Larry Walker Associates, reported on a review of Jackson’s wastewater treatment plant discharge alternatives. His firm did a “peer review” of former city consultant Stantec’s work.

The review looked at the state discharge permit, and alternatives recommended by Stantec and the public. He said the permit, for 400,000 to 710,000 gallons a day of treatment would not allow for any “critical conditions” due to severe drought, and the permit would require “sizing the system” as dictated by critical conditions.

He said a storage and land application area would need to be large enough to hold treated effluent that would be diverted from flowing into the creek for “up to 16 months” during critical drought times. He said “the sizing and costs would increase to meet the letter of the law always.”

Grovhoug said Ken Berry’s alternative, an “upstream reservoir above the treatment plant” was a good idea, but the hydrologic study shows that in trying to dilute the effluent at the source, you would “start to run out of water.” He said it would require dewatering the reservoir, and any water released “must meet the discharge permit.” He said “it would be a nightmare to run” and “it just won’t work. Its problem is in these critically dry years.”

City Manager Mike Daly noted that Berry sent a comment letter over the Aug. 20 weekend asking for an explanation of how his alternative was interpreted, and they are working on an answer.

Grovhoug said continuing with the current discharge could be done with an upgrade at the plant by installing UV disinfection. But he thought metals could be removed with other system changes.

He said UV treatment helps other plants “discharge year-round to creeks,” but for Jackson, it depends on the permit, and oversight of various agencies. He said “the Department of Fish & Game didn’t want your flow to come out of the creek.” Daly said Division of Water Resources also has its own interpretation, and regulations are “ever evolving.”

Grovhoug said a 20:1 requirement for water-to-effluent ratios in Lake Amador is the most strict requirement in the Central Valley Regional Water Quality Control Board’s jurisdiction, and is based on secondary sewer plants, while Jackson’s is a tertiary plant.

Vice Mayor Keith Sweet said “if 20:1 changes tomorrow, are there other things in the water we need to get rid of?” Grovhoug said those include ammonia, nitrate and aluminum, and they could add lime to the water to help eliminate toxicity. He said regarding endocrine disrupters and pharmaceuticals, “no one in the state is being regulated on those in wastewater.”

The full peer review findings are available on the city’s website.

Story by Jim Reece This email address is being protected from spambots. You need JavaScript enabled to view it.