Reunited And It Feels So Good: A Creek and Its Floodplain, Connected Again

An excavator works on the newly reconstructed channel for Squaw Creek in Summer 2015. Felled trees in the foreground will be placed in the channel and on the floodplain to help trap sediment and slow erosion.

Squaw Creek, in the uppermost headwaters of the Middle Fork John Day River Basin, may be on the small side, but it isn’t small in terms of its potential importance to native, threatened Mid-Columbia River steelhead and other resident fish and wildlife species. Squaw Creek joins with Summit Creek 3.5 miles above Highway 7 and together these two streams become the Middle Fork John Day River (Middle Fork). Over the last century, Squaw Creek’s productive aquatic habitat slowly declined. Now, with a new restoration project, the Malheur National Forest and Oregon Department of Fish and Wildlife are working to re-intertwine the disconnected pieces of this ecosystem.

Near its headwaters, Squaw Creek once meandered lazily through a 70 acre meadow, a mosaic of fens, wet sedges and dry sagebrush. When the river overtopped its banks in spring, the floodwaters created slow-flowing alcoves, side channels and backwaters ideal for young salmon and steelhead to hide, rest, and feed in. The connection of floodplain to river meant that more nutrients, insects and other food from the land traveled into the water and was available to the growing fish.  Steelhead traveled hundreds of miles from the Pacific, unimpeded by weir, dam, or culvert, to spawn here.

Connectivity matters: It’s how a river renews itself. Without longitudinal (upstream-downstream) connectivity, animals like steelhead—whose life cycle depends on the ability to move up and down river systems—can’t access habitat. As flows of nutrients, sediment, wood and gravel from floodplain to river are stopped or slowed through loss of lateral (side-to-side) connectivity, the river’s ability to nourish new generations of fish and wildlife becomes impoverished or lost altogether.

In the case of Squaw Creek, Euroamerican settlement in the Blue Mountains brought beaver trapping, logging, grazing and fire suppression to the watershed, which created a laterally disconnected habitat that is no longer a nurturing environment for young fish to grow and thrive. More recently, road-building and log weir installation longitudinally disconnected Squaw Creek, turning it into a series of semi-isolated segments by blocking fish from getting upstream.

Can connectivity be restored to this once-flourishing stream? That’s where Malheur National Forest Fisheries Biologist Kate Olsen and Hydrologist Hazel Owens come in. Olsen and Owens, in collaboration with Oregon Department of Fish and Wildlife, are leading a multi-year restoration project on Squaw Creek that aims to improve stream habitat, cool stream temperatures, and increase both lateral and longitudinal connectivity. 2015 is Year One. If all goes according to plan, a majority of the project should be finished by 2017—but its effects should last long beyond its completion date, and go much further downstream than the project site.

The restoration team’s strategy to undo the disconnection and knit the isolated pieces of Squaw Creek back together is threefold.

First, the team will return the artificially straightened stream channel to its historically winding, meandering flow path. A stream with more curves and meanders in it helps slow down fast-moving floodwaters, reducing erosion and cooling the water by forcing more of it to flow through gravel bars. The team will also provide places for fish to hide from predators by placing logs and root wads, such as would have been historically present, into the stream. They’ll also create places for fish to rest by making more pools. To help create shade and cool water temperatures for fish, the team is planting aspen, willow, dogwood, and alder near the reconstructed channel.

Second, the team will help reconnect the stream with its floodplain. Currently, the stream runs at the bottom of a deeply carved channel, meaning the floodplain is left high and dry even at high flows, because there simply isn’t enough water to overtop the banks.

To accomplish this lateral reconnection, the team is felling trees, which accomplishes two goals: First, it helps return more water to the stream, because trees use a lot of water. Historically, the trees the team is cutting would not have been present, but a century of fire suppression allowed them to invade the meadow. Secondly, the felled trees will be placed in the channel to help trap sediment and raise the streambed’s elevation. Some trees will be kept on the floodplain to slow the flow of raging floodwaters, reduce erosion, and protect riparian vegetation. Eventually, Squaw Creek will be able to overflow its banks and access the floodplain once again, creating the variety of food-rich, slow-flowing habitats so important to young fish.

Finally, the team will focus on restoring longitudinal connectivity by addressing 85 fish passage barriers over the life of the project. In summer 2015 alone, fourteen log weirs throughout Squaw Creek were removed, along with a culvert that blocks both adult and juvenile steelhead passage. This barrier removal will allow fish to access more habitat where they can effectively spawn or feed and grow.

The Forest Service is monitoring the local impact of the project. Meanwhile, other researchers, part of the Middle Fork Intensively Monitored Watershed collaborative, will monitor downstream of the project site to see if, and how, the Squaw Creek project impacts habitat downstream in the Middle Fork.

After all, this is what connectivity is all about. What goes on upstream in the headwaters of a river can often have a profound impact on the conditions downstream.  Planting shade trees to cool water temperatures for fish, for example, might not work if there is no streamside vegetation for miles upstream of the project, meaning the water flowing through your shaded project is already too hot.  On the other hand, if you effectively restore enough miles of upstream habitat, your downstream restoration project might work. This is what biologists call ‘cumulative impact’—smaller impacts adding up to a whole that is bigger than the sum of its parts. This is part of why connectivity matters so much.

By knitting together a headwater stream with its floodplain, and splicing its isolated segments back together with barrier removals, the Squaw Creek restoration team is restoring part of the inherent nature of this dynamic system: connectedness. Stay tuned for future updates on the Squaw Creek restoration as the project progresses!

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- Emily Davis
Monitoring Coordinator, Oxbow & Forrest Conservation Areas
Confederated Tribes of the Warm Springs Reservation of Oregon