I-5’s storm water will be treated in ponds in park

EVERETT – Each year, an estimated 153 million gallons of rainwater falls along the six miles of I-5 in Everett.

For nearly 40 years, all that rain has washed untreated into the Snohomish River. Along the way all the oils, bits of rubber and other pollutants that fall onto the highway have been flushed into Possession Sound.

Now, as part of the state’s $263 million ongoing I-5 widening project, that water will be treated before it is released back into the river, said Mike Cotten, project director for the state Department of Transportation.

The state has built four separate water treatment plants along the length of the widening project, including one that, working with the city of Everett, creates a series of attractive wetlands near the future Everett waterfront project.

The ponds have a short trail that loops through them and ties in with the Riverfront Trail that follows the Snohomish River. Native plants will be planted in and around the ponds next spring, adding habitat and beauty to the area while pulling out toxins from the water.

“It’s a truly wonderful facility,” said Dave Davis, Everett’s director of engineering. “It complements the city’s interest and vision for the riverfront area.”

The water that drains from the highway has to cross over railroad tracks to get down to the treatment ponds, Cotten said. He said the city of Everett contributed to the project to turn what would simply have been a bridge into a pedestrian bridge and aqueduct.

When it opens next summer, that bridge will for the first time give Lowell residents access to the river, the trail and the new wetlands without having to take a long walk around to an at-grade track crossing.

“This bridge is a big deal,” said Jules Anslow, a Lowell artist who works at Lowell Artworks and lives nearby. “It takes you right to the trail and it’ll take you right to the ponds, too. The birds have already started to populate it.”

She said she has seen herons, eagles, ducks and geese use it.

“It’s beautiful just to look at,” Anslow said. “It reflects the trees and the sky around it. It also retains the view. We know for sure we’re going to keep our view of the river and the mountains” because that land won’t be developed.

State law requires that any time new lanes are added to an old state highway, all of the rain that drains from that length of road has to be treated before it is released, Cotten said. He said it’s an important and expensive feature in the project.

The Everett I-5 widening project, scheduled to finish as early as February, adds new carpool lanes from the Boeing Freeway to the Snohomish River. It also adds new merging lanes between U.S. 2 and 41st Street SE.

The northbound merging lane already is open and the carpool lane is on track to open by the end of the year, Cotten said. The southbound lanes won’t be finished until February at the earliest.

Drivers are already using a new 41st Street SE overpass — one ramp is still to come — and a flyover ramp from northbound I-5 to Broadway. Five new overpasses also are being built and 18 were widened.