Clackamas Watershed Collects Pollutants And Drinking Water
by Cassandra Profita
August 12, 2013
On a nursery in Boring, researchers are demonstrating a new high-tech pesticide sprayer for a dozen growers.
Oregon State University extension entomologist Robin Rosetta explains how this so-called “smart sprayer” uses a computerized sensor to detect the shape of plants and tell the nozzles on the machine where to spray and where not to spray. The result, she says, is a dramatic reduction in the amount of pesticides sprayed on empty spaces.
Studies by the U.S. Geological Survey have found 63 different pesticides and herbicides in the Clackamas River Basin. And testing shows some of those chemicals are winding up in the drinking water communities take from the river.
Sam Doane sits on the Clackamas River Basin Council, which looks out for water quality. So he knows about potential sources of pollution in the water. He’s also a horticulturist with Frank J. Schmidt & Son Nursery, so he’s working to reduce the potential for pesticide runoff on his land.
“We live in an environment where there are a number of streams and rivers adjacent to the property, and we need to be cognizant of what’s happening in those streams and rivers,” he said.
Doane spent two years testing the smart sprayer at his nursery in the Upper Clackamas River basin. The result was a 65 percent reduction in pesticide use.
“That’s 65 percent less material that has the potential to be an environmental concern,” said Doane.
Many miles downstream from Doane’s nursery, Kim Swan is one of the people concerned about pesticides on the Clackamas.
She works for the Clackamas River Water Providers – a group that represents nearly 400,000 people who rely on the river for drinking water. The group includes the cities of Lake Oswego, West Linn, Oregon City, Estacada, Gladstone, Happy Valley, Damascus and a lot of the surrounding rural communities.
Swan says a lot of her customers think their water is coming from the protected watershed of Portland’s Bull Run.
“The Bull Run is unique because it’s a much smaller watershed and it’s protected. The public doesn’t have access. There’s no agriculture, no logging,” Swan says.
But the Clackamas watershed is different.
“Our watershed, on the other hand, is very large. It’s approximately 940 square miles.”
Swan points out that on the many miles upstream from drinking water intakes on the Clackamas, there are nurseries, timberland, wastewater treatment plants, houses with septic systems, golf courses and state and county roads.
The Lake Oswego water intake on the Clackamas is just across from the Tri-City Wastewaster Treatment facility.
Water testing in the river reveals numerous pollutants that could be coming from any of those places. Those pollutants include pesticides, gasoline components and flame retardants. But it’s hard to trace the chemicals to any one source.
For Doane, reduction of pesticide use is one answer. In recent years his nursery has reduced its pesticide use by 50 percent even without the smart sprayer. But the new technology could further reduce the potential for runoff.
“I’m really excited about it. I think it provides a great opportunity for growers and landowners and the community at large to reduce environmental impact from pesticide use,” Doane says.
Of the 63 different pesticides and herbicides detected in the Clackamas River Basin, 15 of them were still present in treated drinking water samples.
The levels were really low, and they didn’t exceed any of the limits set by the Environmental Protection Agency for what is safe to drink. In some cases, the amount of pesticide was less than 1 part per trillion, which is the equivalent of one drop in 20 Olympic-size swimming pools.
Kurt Carpenter is a researcher for the U.S. Geological Survey. He did the drinking water studies of Clackamas River water and says the results still raise concerns. Many of the chemicals detected in Clackamas drinking water aren’t regulated at all by safe drinking water laws. So their potential health effects haven’t been studied – especially when you mix them together.
“So, when you find a contaminant at these exceedingly low levels, it doesn’t necessarily mean they’re not going to have an effect – especially when you have two or three different chemicals that might be acting together in an additive or synergistic fashion,” Carpenter says. “It just raises a lot of questions about what does it mean when these things are detected at all.”
In response to the findings, the communities that take their drinking water from the Clackamas are working on ways to prevent pollution before it gets into the river. Swan, who heads the water provider organization, has commissioned detailed maps of aging septic systems upstream that might be at risk of leaking. She’s organized pesticide and pharmaceutical drug collection events. And she’s looked at offering financial incentives for farmers upstream to get organically certified.
“When studies like this come out we’ll often get calls from our customers saying ‘What’s this? What are you doing about it?’ We tell them that we’re aware of it. That we’re trying to be proactive. That our treatment plants have the ability to treat for most of this stuff. Our goal is to not let them get worse,” Swan says.
Despite the potential threats to drinking water on the Clackamas, communities still see the river as a great drinking water source for the future. So great, in fact that they’re asking to take more water from the river.
On the riverbank near Gladstone, workers drive piles for a new water intake facility. The city of Lake Oswego has plans to double the amount of water it takes from the river. And to do that, it will need a bigger intake system.
“Our water system was built in the 1960s,” says Jane Heisler, spokeswoman for the Lake Oswego Tigard Water Partnership, “and we have had a few summers in the last five years or so where we’re bumping up against the max we can deliver with our current system.”
Lake Oswego currently has access to 16 million gallons a day of Clackamas River water. But in the future it plans to tap its full 38 million gallons a day in water rights and sell some of that water to the city of Tigard to pay for the new intake and an advanced water treatment plant.
“We don’t expect that we’ll need that water for many, many years, but at some point in the future we will,” Heisler says.
Other communities are looking to the Clackamas for more water as well. Some are preparing for growth in response to Metro’s expansion of the urban growth boundary into the Happy Valley and Damascus area.
Three other municipalities have applied to further develop their water rights on the river. Altogether, the requests add up to a water demand of 150 cubic feet per second.
That volume has environmentalists worried.
“We’ve already got a critical problem out there.”
John DeVoe is the executive director of the environmental group Water Watch.
He’s worried about the impact of additional water withdrawals to three threatened species of salmon and steelhead on the river.
“If we take more water out of the river, scientists have said we’re going to reach flow levels that are too low for fish. So we’re trying to prevent flow levels from getting that low,” DeVoe said.
DeVoe’s group has gone to court to prevent Lake Oswego, Tigard and three other municipalities from removing water from the river when it’s needed for fish.
The case has made it to the state court of appeals. Oral arguments are expected sometime this fall.