City urges public to dispose of toxic substances properly after increase of harmful discharge in wastewater system


During the week of Oct. 9, the City and Borough of Juneau Utility detected and responded to three separate instances of discharges of toxic and prohibited substances into the public sewer system.

This comes after CBJ Utility responded to a residential heating oil tank last month at the Juneau Douglas Treatment Plant.

CBJ Production & Treatment Manager Chad Gubala explained each separate instance that took place last week.

“We had in one instance we had a very low pH slug come through one of the plants very early in the morning. So, there was a discharge of some type of acid into the system. The same plant then later in the day got affected by diesel discharge,” he said. “Then, a different plant, we don’t actually know what the substance is right now. It’s still undergoing testing, but we intercepted and took out of line, a very large plug of a milky white substance that we’ve yet to identify.”

None of these substances belong in the sewer system.  

The acid and the diesel were at the Mendenhall Treatment Plant and the unidentified milky substance was at the Auke Bay Treatment Plant.

Gubala said each of these substances poses various threats and costs a lot for the community-owned system to manage.

“Under some circumstances, they can affect human health, they can potentially affect the health and well-being of the operators that we have that operate our waste treatment facilities and also maintain our collection systems. So, we’re very concerned about their health and safety,” he said. “If there’s a large enough discharge and it gets entirely through our treatment plant, and it can discharge to the environment, it can affect people that way through the direct discharges out to the environment.”

Gubala said they are concerned about the environmental impact on marine life. There is also the issue that sometimes the toxicants can create secondary effects on the treatment plant itself.

Discharging toxic and prohibited substances to CBJ’s sewer system constitutes a violation of CBJ’s Sewer Code, Section 75.02.080 – Use of public sewers;

  1. No persons shall discharge or cause to be discharged to any public sewer any harmful waters or wastes, whether liquid, solid or gas, capable of causing obstruction to the flow in the sewers, damage or hazard to structures, equipment and personnel of the sewage works, or other interference with the proper operation of the sewage works.

CBJ Utility staff are currently tracking the source of the discharges detected last week and are conducting an investigation to determine the responsible parties. 

Gubala directs community members to dispose their waste with RecycleWorks.

“I think the biggest thing to basically indicate as well is that we have a lot of different ways of helping people dispose of materials properly and cheaply,” he said.

He encourages residents to hold off on putting anything down the storm drain and divert their waste to the right place.

He said usually, events like these are rare and much more spread out. Gubala gave remarks on September’s incident.

“That was significant enough to actually create a pH violation and, you know, an interruption of our treatment process as well. These plants receive, you know, sewer discharges at the rate of anywhere between one to 3 million gallons a day,” Gubala said. “So, if we actually detect something at a plant, it’s got to be fairly significant because it’s been diluted quite a bit.”

Safe, legal, and often free disposal of toxic materials is easily accomplished by bringing those materials to Juneau’s RecycleWorks, which is located at 5600 Tonsgard Court/Juneau’s landfill.

Operations Manager Stuart Ashton shared details on RecycleWorks.

“There’s going to be people there to greet you and you can drop off electronic waste, basically anything that has a battery or plugs into a wall. As long as it’s not a refrigerator or freezer. They’ll accept that there,” he said. “That place will also take used and old gas, oil, thinners, paint, and anything you will find under your kitchen sink or in your garage.”

RecycleWorks is open from 8 a.m. to 4:30 p.m. For residents, it’s open Thursday, Friday, and Saturday, and businesses are by appointment only.