Project set to rechannelthe Grays

Following last week’s drenching storm, the Grays River flowed in two channels across what was once the hay field at Gorley Springs.

Located at the head of the lowland portion of the Grays River Valley, the Gorley farm is at the point where the river spills out of its steep gorge. The river spreads across the wider valley, loses momentum, and deposits the heavier objects carried in its currents. The Gorley family and allies such as the former Upper Grays River Flood Control District, worked to keep the main channel to the north side of the farm, but in December, 1998, the river ate through a dike protecting the farm and cut a new channel. The event, called an avulsion, cut off access to the family farm and park areas and also washed away a downstream house and severed the Western Wahkiakum Water System main. The flooding effectively forced relocation of the water system well site and destroyed small spring fed channels which chum salmon used for spawning.

Ten years later, work should actually get started to rechannel the river.

Amy Ammer, a habitat restoration specialist employed by the Columbia River Estuary Study Taskforce, has been working on the Mark Linquist/Gorley Springs Project since she joined the organization last year. A consulting engineer presented its draft conceputal design report earlier this month, and the project is scheduled to go to bid in early 2009.

"This is the first phase of a long range project," Ammer said November 13 along the river bank.

The goal is to get the river back into a stable stream channel. Once the river is stable, the spawning channels can be redeveloped, and the Gorley family will be able to use their land again.

The project calls for excavation of a new channel and placement of wood structures to help channel the river and dissipate flood energy.

Six engineered log jams will be constructed of tree trunks with root wads. They'll be placed so that they direct the current away from the Gorley Family buildings on the south bank and into the preferred channel. The jams will catch additional wood in the river and enlarge themselves and promote sediment deposition by breaking up stream power and creating side channels.

The log jams will direct the river toward the new, excavated channel, and a new avulsion should occur during a freshet to lead the streamflow into the new channel.

In an area now covered with alder trees, logs will be placed upstream of the trees. In freshets, the logs will catch on the trees, break up stream flow, and catch sediment.

The contractor will construct flood fencing in the upper and lower ends of the project to deflect freshets away from the south bank property.

"The Gorleys have already constructed one of these between the new channel and their house," Ammer said. "It seemed like a good idea, and we're using it, too."

The flood fence consists of logs driven upright into the ground with other logs attached horizontally to form a six-foot wall. Set back from the river, they'll help stabilize the south bank and deflect current and debris during freshets.

At the lower end of the project another fence and some woody debris structure will reduce velocities near the confluence with the West Fork of the Grays and reduce erosion of Fossil Creek Road.

Ammer said construction will occur during the summer dry season and shouldn't impact stream channels. The contractor will access the the site with a temporary bridge which will be removed.

An important concern, she said, is that the projecton won't adversely affect neighboring property owners.

"I'm requiring the engineer to include a zero rise analysis," she said, referring to the principle that construction in a flood plain shouldn't raise the water level in other areas.

Bonneville Power Administration is funding this project directly. They have a provincial review of proposed projects, Ammer said, which includes a scientific review of the validity of the project.

The total grant from BPA is $1.2 million, spread over three years between CREST for implementation and Pacific Northwest National Lab for monitoring and research.

Research leading to the project last summer involved Naselle/Grays River Columbia Estuary Environmental Education Program students from Naselle High School; they completed a habitat assessment survey, which included a longitudinal survey, cross section surveys, vegetation plot survey, water temperature and dissolved oxygen stations, GPS stationing, and large woody debris survey.

"This helps everyone interested in chum salmon habitat quantify what chum prefer," Ammer said.

The Gorleys are pleased that something is being done to restore use of their land, and they hope the project will set an example for projects in other areas on the river, John Gorley said this week.

"It's been a long process," he said. "About five years ago, Karen Bertroch came to us at the suggestion of (late county Commissioner) Mark Linquist to talk about what could be done."

Linquist and Bertroch, a grant writing consultant working with groups involved in Grays River management, set up a meeting with regional managers of the Washington Department of Fish and Wildlife, and they began talking about what could be done.

"The agencies are very limited in what they can do; it has to benefit fish," Gorley said.

"If you keep an open mind and allow for the fact that the agencies are restricted, and if you work with them, you can make some progress.

"I think this will be a good project that can serve as an example of what can be done on the river."