Copper, zinc levels highlighted in latest Kenai river study

Sep 6, 2018


Gulls are the main culprit in exceedingly high levels of fecal coliform bacteria found in the lower Kenai River.
Credit John Reed/USGS

The salmon run has gone from red to silver, but some summer projects are still being wrapped up on the Kenai River. The Kenai Watershed Forum will conduct its last sample of the season Friday, searching for bacteria and their sources in the river.



Watershed Forum Executive Director Branden Bornemann told the Kenai city council Wednesday night that they’ve been able to do more in their research this year than simply identify levels of bacteria. Namely, fecal coliform. They’ve been able to analyze those contaminated water samples and pinpoint what kind of animal left their mark.

“No surprise to anyone, the highest contributor of bacteria to the mouth of the Kenai River were gulls. Anybody that’s lived here, spent time on the beach can understand this. We did get a few other hits. We got a horse, we got a pig, we got a dog and I believe we got a human. But the principle point is gulls are the source contributor of this bacteria.”

Studies of this sort have been going on for nearly a decade because those bacteria at the mouth, and other factors upriver, put the Kenai in violation of certain water quality standards, and it happens pretty consistently every year. The common wisdom is that regardless of human activity, which is to say dipnetting, there would still be a lot of gulls hanging around the mouth of the river, eating fish, and leaving the remains of their digestive efforts near and in the water. So, in partnership with the Department of Environmental Conservation, researchers are working to establish baseline data over the long term.

“We’ve set ourselves up to be able to talk about this as use patterns change, as recreation patterns change, as the ecosystem itself changes," Bornemann said.

And the ecosystem itself is changing. Those same sampling exercises have also turned up elevated levels of zinc, copper and other pollutants, which is to be expected in any area as it develops. Bornemann says those numbers are getting to a point on the Kenai where more research can be justified.

“If we end up listing it as a Category 1 or Category 2 based on this data, that opens the door to us for further investigation. It gives us an opportunity to spend a little more money, target our sampling, and figure out if we have a source, how often that source is present and potentially, what we can do about it.”

A likely first step is getting all of this information into the state’s integrated water report, but that’s been a struggle. DEC is supposed to turn in such a report to the Environmental Protection Agency on an annual basis. Finger pointing over other water quality issues on the Kenai has held that up, and it’s unclear when the state's report will make its way to the feds.


Note: Branden Bornemann sits on the KDLL Board of Directors.