Talkeetna gets sewer

MAT-SU -- Thanks to two significant grants -- nearly $1.9 million from the Department of Environmental Conservation and a second for $1.3 million from the U.S. Department of Agriculture's Rural Development Agency -- Talkeetna residents will soon have a working sewer system.

To celebrate, the USDA presented a $1.3-million check to Borough Mayor Tim Anderson Saturday at a Talkeetna Elementary Earth Day celebration.

According to information from the Rural Development office, Talkeetna's existing sewer system was completed in 1993 and serves about 500 people. The system, long plagued with inflow and infiltration problems, was issued a notice from DEC last year for violating the department's regulations.

"USDA Rural Development is pleased to help the borough provide Talkeetna with a safe sewage disposal system," said Frank Muncy, USDA's assistant state director. "The existing system is approaching failure and poses a threat to the health of Talkeetna residents and visitors. USDA Rural Development is committed to helping to build utility systems that are sustainable. It is vitally important that the Talkeetna water and sewer system be operated and maintained to meet local needs over the long term. Failure is not an option that anyone should accept."

The problem with the Talkeetna sewer system has a lot to do with geography, according to Jim Swing, the borough public works director. Talkeetna has a high water table that leaked into the sewer system at various points throughout the community, causing the system to process much more water than it was designed to.

"We are treating way over the amount we should be," Swing said.

After reaching the treatment area, the water filtered through the two lagoon cells and into the percolation cell, where it was supposed to gradually flow out into the Talkeetna River. The water in the percolation cell contained a significant amount of proteins, which encouraged the growth of what Swing called a vegetative mat. The mat covered the bottom of the cell and did allow liquid to percolate through, blocking the system.

"We removed the mat a few times," Swing said.

But after the mat was removed last year, the bottom of the percolation cell was determined to be too close to the area's water table. DEC standards call for at least a four-foot separation, and the cell was less than four feet above the table.

The borough hired a consultant to redesign the sewer system and, according to present plans, the percolation cell will be lined for use as a third lagoon. Instead of a replacement percolation cell, Swing said his department is considering using wetland swails instead. The swails are a relatively new technology in which native and newly planted wetland grasses and plants feed off the nutrients in the treated water.

"[It's] a new technology where plants that are put into that wetland … actually take out some of the sewage," Swing said. By the time it flows into the Talkeetna River, the water will be much cleaner than the tertiary treatment the system provided before.

But Swing said that concept has not been finalized just yet.

"This is a proposal," Swing said. "It's not designed yet."

Swing said it's likely the new system will be constructed this year, as will a few other projects that will be funded by the grant money. The sewer piping around Talkeetna will be evaluated and repairs will likely be made to prevent the present inflow problem stemming from the high water table. Manholes, service connectors and pump stations will be repaired where necessary and a maintenance facility -- with additional maintenance equipment -- will be added to allow more on-site work to be completed, Swing said.