February 2023 Community Events

Take advantage of the volunteer opportunities and events offered by our partners this month!


City of Hillsboro/Jackson Bottom Wetlands

SOLVE

Friends of Trees

Friends of the Tualatin River National Wildlife Refuge

The Wetlands Conservancy

The Intertwine Alliance

  • No events in Washington County this month!

    For a full list of Intertwine Alliance events, click here.

Tualatin Soil and Water Conservation District

Tualatin Hills Park & Recreation District

Tualatin Riverkeepers


January 2023 Community Events

Take advantage of the volunteer opportunities and events offered by our partners this month!

City of Hillsboro/Jackson Bottom Wetlands

  • Wednesdays in January, beginning January 11, 12:00pm: Nature at Noon

    For a full list of City of Hillsboro/Jackson Bottom Wetlands events, click here.

SOLVE

Friends of Trees

Metro

The Wetlands Conservancy

The Intertwine Alliance

  • No events in Washington County this month!

    For a full list of Intertwine Alliance events, click here.

Tualatin Hills Park & Recreation District

Tualatin Riverkeepers

Washington County Parks

December 2022 Community Events

Take advantage of the volunteer opportunities and events offered by our partners this month!

City of Hillsboro/Jackson Bottom Wetlands

SOLVE

Friends of Tryon Creek

  • Saturdays in December (starting December 10), 10:00am: Guided Hikes

    For a full list of Friends of Tryon Creek events, click here.

Friends of Trees

The Wetlands Conservancy

The Intertwine Alliance

Tualatin Hills Park & Recreation District

November 2022 Community Events

Take advantage of the volunteer opportunities offered by our partners this month!

City of Hillsboro/Jackson Bottom Wetlands

SOLVE

Friends of Tryon Creek

Friends of Trees

Tualatin Riverkeepers

The Wetlands Conservancy

The Intertwine Alliance

Tualatin Hills Park & Recreation District

Dam Removed Carefully in Steps to Protect Fish and Habitat

For decades, an obsolete dam at Balm Grove, 12 miles upstream from the confluence of Gales Creek and the Tualatin River, has acted as a major fish passage barrier for aquatic life in the Tualatin River Watershed. Its removal in September 2022 opened up nearly 35 miles of prime habitat to threatened species such as the winter steelhead and Pacific lamprey, a major step forward in a larger statewide effort in fish habitat restoration. 

A multi-step process ensured the safety of local species and protected the health of the surrounding ecosystem. First, crews dug a diversion channel to temporarily reroute the creek. Culverts were installed so construction crews could access the work site.

Once the diversion channel had been graded and secured with erosion control, a cofferdam (an enclosure built within a body of water to allow the enclosed area to be pumped out) was erected, and 25% of the creek’s flow was diverted into the channel. Starting with a slow flow helped to minimize the dirt moving downstream while also signaling to fish that it was possible to swim upstream through the new channel.

The stream’s diversion marked the first time since 1936 that fish had been able to successfully get around the dam. Crews were heartened to see that salmon almost immediately started to move upstream.

Balm Grove Dam Removal Gallery
Aerial view of the construction site, showing the diversion channel, access culverts, cofferdam and dam. Water pumps beside the dam channel water into an adjacent field (top right).

Aerial view of the construction site, showing the diversion channel, access culverts, cofferdam and dam. Water pumps beside the dam channel water into an adjacent field (top right).

A hydraulic hammer breaks up concrete from the dam. The dam’s demolition resulted in seventy truckloads of concrete and steel rebar, all of which was recycled.

A hydraulic hammer breaks up concrete from the dam. The dam’s demolition resulted in seventy truckloads of concrete and steel rebar, all of which was recycled.

The cofferdam directs water into the channel, while orange and green sandbags hold the plastic down.

The cofferdam directs water into the channel, while orange and green sandbags hold the plastic down.

The dam before its removal, after water has been diverted from the creek.

The dam before its removal, after water has been diverted from the creek.

Crews capture the remaining fish, count and catalog them, and then reinsert them downstream.

Crews capture the remaining fish, count and catalog them, and then reinsert them downstream.

A seine net prevents fish from coming back upstream into the job site after they have been salvaged.

A seine net prevents fish from coming back upstream into the job site after they have been salvaged.

Thanks to the coordinated efforts of our partners, more than 600 salmonids were salvaged in the dam removal process.

Thanks to the coordinated efforts of our partners, more than 600 salmonids were salvaged in the dam removal process.

A crew member holds a steelhead trout.

A crew member holds a steelhead trout.

Crews recover a cutthroat trout.

Crews recover a cutthroat trout.

“Instant gratification is rare in ecological restoration, but we got to experience it by helping Clean Water Services remove a dam that has been impeding migratory fish passage since the ‘30s,” Matt Koozer of Biohabitats notes. “Just like that, miles of habitat opened up for species like coho salmon, Pacific lamprey, and winter steelhead along Gales Creek.”

Once construction of the cofferdam was complete, the creek’s flow was completely diverted. Crews salvaged the remaining fish and removed the dam.

A coalition of Tree for All partners, together with Biohabitats, manage the site’s rehabilitation. Next summer, partners will insert logjam structures to provide shelter and habitat to native species. They will also revegetate the site with native plants and excavate the nearby floodplain to ensure that the creek is able to rise from its channel and saturate the adjacent cottonwood forest.

“Dam removals are the single most important thing we can do to restore our rivers and streams,” says Scott McEwan, executive director of the Tualatin River Watershed Council. “The removal of the dam at Balm Grove is a major win for our environment, and it couldn’t have been done without the coordination and commitment of our partners.”

Stay tuned here for more updates! To learn more about the history of this project, you can read the Balm Grove case study.

Many thanks to our partners on this project: Clean Water Services, the Intertwine Alliance, Metro, Northwest Steelheaders, Oregon Department of Fish and Wildlife, Trout Unlimited, Tualatin River Watershed Council, Tualatin Riverkeepers, and Tualatin Soil and Water Conservation District.

Since 2005, regional partners have been collaborating to restore the Tualatin River Watershed.

Today, they are exploring what comes next.