Willamette Confluence River Restoration Photo Story

Photos by Austin Melcher; Story by Willamette Partnership Staff and Austin Melcher

When we look at a river through the lens of a scientist, we can see there’s more than what meets the eye.

Our summer fellow, Austin Melcher, visited the Oregon Nature Conservancy’s river restoration project, Willamette Confluence, to run our Flood Attenuation and Impact Mitigation Tool (which, by the way, calculates a restoration or development project’s effect on a floodplain’s ability to store and slowly release surface waters and, therefore, reduce flooding downstream). While working, Austin captured a series of photos of the different river restoration techniques The Nature Conservancy used to reconnect the Middle Fork of the Willamette River back to its historic floodplain and improve fish and wildlife habitat in and along the stream. What’s interesting about this particular restoration project is one) it leverages the use of old mining pits, and two) its size: It’s 1,270 acres.

Check it out!

In the middle of the river here you see the remnants of what used to be a strip of land, also known as a berm, that was removed, by redistributing the soil, to expand the river’s access to the floodplain. Now the river has more area to spread out during heavy rains and juvenile fish have shallower, slower waters to grow up in.

Removing the berm on the Middle Fork of the Willamette River created riffles and gravel bars, which are great for fish rearing habitat!

(Learn more about Willamette Partnership’s 6 Strategies for Smarter Floodplain Management here.)

Here we see a side pool area that now exists because the river was reconnected to its historic floodplain. The increased stream bank and floodplain access can slow down flood flows and provide a diversity of habitats for fish and invertebrates living in the river.

This channel where the birds are now hanging out used to be a hollowed out gravel pit used by an old mining operation. A section of the berm was removed to create a backchannel for the river, improving flood attenuation and wildlife habitat. Sidenote: Austin is standing on a section of the berm that was intentionally left to protect the City of Springfield’s surface water intake on the other side of the river as well as the water rights of other downstream users.

Here’s an aerial of part of the restoration site that shows (in blue) the part of the berm that was removed and the new backchannel that was formed to create more floodplain access and river complexity. 

A random pile-up of woody debris? No, this is an engineering feat of over 50 logs used to open up a side channel for the river and to prevent the existing stream bank from eroding. Kind of like an iceberg, two-thirds of the logjam is underground or underwater, creating shade and habitat for fish and adding to the stream’s complexity. The standing logs, used as giant stakes to help hold the pile in place, create new, riverfront real estate for birds to perch.

(Learn more about our ecosystem service quantification tools and policy templates here.)

Here we’re looking to the left of the above wood installation. This is the side channel that it formed, reconnecting the river to the floodplain and creating more habitat for fish and other wildlife. The green vegetation we see are native plants that were planted as part of the restoration effort.

More

If you’d like to visit the Willamette Confluence restoration project, The Nature Conservancy offers free guided tours and volunteer opportunities.

Did you know we’re helping utilities, regulators, and conservation groups make sure their investments in improving water temperature in the Willamette River go where fish need them most? Learn more here!