Sauk-Suiattle Tribe monitoring stormwater in Darrington

DARRINGTON – In the foothills of the North Cascades Mountains, the rivers still run clear.

Elsewhere in the region, water near large cities has been polluted and salmon habitat degraded. But the Sauk River, which runs past the small mountain town of Darrington, is relatively pure.

The Sauk-Suiattle Indian Tribe would like to keep it that way.

In partnership with the Darrington town council, the tribe’s Natural Resources Department is monitoring stormwater runoff into the Sauk River.

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With a General Assistance Program grant from the U.S. Environmental Protection Agency, the tribe bought an automatic sampler to collect runoff during storm events.

The sampler’s flow meter sits in the bottom of a culvert at Darrington’s main outfall. When rain flushes runoff into the pipe, the sampler is triggered to suck up water into 24 plastic bottles. The sampler’s computer graphs the storm’s flow fluctuations to determine how much stormwater from each bottle to include in a composite sample for the lab.

“What you want is the stuff coming off the streets and you want it in a representative sample,” said Scott Morris, watershed manager for the tribe.

The tribe is having the water tested for a variety of potential contaminants, including dissolved metals, such as copper, lead and zinc. With a population of about 1,500, Darrington does not have much of a water pollution problem, especially when compared to bigger cities.The data so far do not show alarming levels, Morris said. But copper, which is deposited on pavement as shavings from brake pads, can be deadly to salmon even in very small amounts.

“I’m having the lab test at levels lower than they normally do because this is a pristine water here,” Morris said. “Three parts per billion of copper is still a level that has been shown to affect juvenile fish. That’s pretty minute. It turns off their escape mechanism – their alarm pheromone – and makes them more vulnerable to predators.”

It also impairs salmon’s breathing, brain function and sense of smell, interferes with migration and depresses the immune system.

Results of the water sampling are being analyzed. Morris hopes to continue the monitoring as an anti-degradation measure and to track trends. The tribe has the advantage of starting water quality monitoring before the river has been contaminated by development.

“It’s pretty clear water to start with, let’s make sure it stays that way,” he said.

For more information, contact: Scott Morris, watershed manager, Sauk-Suiattle Tribe at 360-436-0347 or [email protected]; Kari Neumeyer, information officer, NWIFC at 360-424-8226 or [email protected].