However, Wasilla — like Palmer — is facing regulatory issues to the attention of city officials.
City sewer service started in the late 1980s, Wasilla Public Works Director Archie Giddings said. The initial money came from a federal grant aimed at making Wasilla a test case for a small-scale treatment method for small communities, he said.
 ROBERT DeBERRY/Frontiersman Wasilla Public Works Director Archie Giddings talks about the forced main system for waste treatment that is used by the city. Behind Giddings is a sludge digester where sludge is cooked underground then put out to dry. Once dry, it'€™s spread over drain fields. |
The pump vault then forces the liquids through small, plastic pipes to the treatment plant off of Old Matanuska Road.
Once the liquid reaches the treatment plant, it runs through a screening process then drains into a lined pond. The water flows from the beginning of one pond to the end of a second, being aerated in decreasing amounts as it goes.
The air stimulates naturally occurring bacteria that feed on the remaining solids in the water. No chemicals are ever added.
“All you need is air and heat. We don’t have a lot of heat, so we use a lot of air,” Giddings said.
At the end of the second pond, the water enters one of nine drain fields. Each one-acre drain field acts the same way a leach field does for a private septic system — filtering out the bacteria before the water re-enters the water table.
To treat the solids, each building’s tank is pumped about once every three years. The non-organic materials are filtered from the solids, and the solids are combined with what is screened from the liquids.
This sludge is cooked in an underground digester then laid out to dry. Once dry, it’s spread over the top of the drain fields.
“We get great grass,” Giddings said.
Again, the only things added to the sewage throughout the process are heat and oxygen. It is easy to heat the buried sludge digester, but the two lagoons are completely exposed.
The bacteria in the lagoons cannot survive underneath ice. For the six months of the year when the ponds are frozen, the natural breakdown process slows way down, Giddings said.
The effluent water is tested by wells 100 feet away from the point of discharge. State law requires it to meet drinking water standards, but Wasilla’s discharge is consistently too high in nitrates, Giddings said.
To solve this, Giddings would like to cover the lagoons so the bacteria can operate year-round. This would also allow the sewage to be treated in batches, increasing the efficiency while reducing the nitrates even further.
While the solution is known, the urgency is lacking. Because Wasilla operates under state permits, they do not face the harsh federal punishments Palmer does for being out of compliance.
What’s more, Giddings said, the state recognizes the terms of the contract are unrealistic for Wasilla’s current operation. Safe drinking wells have to be drilled to at least 30 feet, he said, but the effluent is still in the surface water at the testing site just 100 feet away. The water has not had time to seep through enough dirt for the natural cleaning process to occur, Giddings said. Testing further down, the water table confirms the discharge is not affecting any wells, he said.
Thus, the state is allowing Wasilla to operate the facility at its current level.
While Palmer received a grant from the American Recovery and Reinvestment Act to solve a similar situation, Giddings said Wasilla is not eligible because the project is not “shovel-ready.” But Giddings did say he has a $1 million federal earmark to pay for covering the lagoons, but the grant must be matched by state funds.
There may not be the same urgency and same availability of funding, but Giddings said he can apply for an larger permit once the ponds are covered. The facility is allowed to process about 400,000 gallons of wastewater every day, a level the facility is currently operating at. Covered, he is comfortable that could be increased to 800,000 to 1 million gallons per day. That would satisfy Wasilla’s growing sewer needs for at least the next 10 years, Giddings said.
Contact Todd L. Disher at todd.disher@frontiersman.com or 352-2252.
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