Ochoco Preserve Restoration Design

The Deschutes Land Trust has developed a restoration plan for the Land Trusts Ochoco Preserve. Ochoco Preserve is a 185-acre property on the western urban growth boundary of Prineville, Oregon. The preserve includes 1.25 miles of the Crooked River, the confluences of Ochoco and McKay creeks with the Crooked River, a historic Crooked River oxbow, and dozens of acres of historic/potential wetlands. The primary objective is to restore quality habitat for Mid-Columbia River spring Chinook and Middle Columbia River Steelhead.

Ochoco Preserve is currently in farm use, with 127+ acres of irrigated land devoted to raising alfalfa and grass hay for livestock. Over the past 150 years, the Preserves streams were relocated, straightened, and diked, greatly reducing their ecological value. Oxbows and wetlands were filled to facilitate agricultural use. Restoring the Preserves streams and wetlands will be complicated and expensive. Given the complexity of the site, we have invested significant funds in a conceptual design process that will help identify, prioritize, and sequence restoration actions. The technical restoration design developed here will tier from that conceptual design.

The purpose of the project was to develop a plan to reestablish ecological processes while providing limited public access in strategic locations in order to allow for community engagement and education about local ecology. The plan identifies, prioritizes, and sequences actions that create the pathway for an accessible, ecologically functional Preserve.

Project objectives included in the plan are as follows:

Increased channel length, complexity, and floodplain connectivity of McKay Creek;

Enhanced channel complexity and riparian function of Ochoco Creek, including enlarged floodplain interaction;

Added complexity and channel length to the Crooked River and improved floodplain interaction;

Increased production within, and use of, the waterways on the Preserve by spring Chinook salmon and summer steelhead in order to support reintroduction efforts;

Reestablished wetlands and uplands that contain native plant communities;

Strategically placed nature trails containing interpretive sites that inform and educate Preserve visitors; and Connection of the nature trails to the city of Prineville via a pathway along the highway and footbridges over Ochoco Creek and the Crooked River to the city of Prineville wetland
complex.

The PCSRF funding provided for this project was used to support the design process and result in an engineered design ready for implementation. The restoration plan and design have been submitted along with this report as a deliverable for this funding agreement.

Worksite #1 Activities:

All work occurred at the 184-acre Ochoco Preserve, Crook County, Oregon (Taxlot 1415260000601). We designed restoration actions for all key site components, including McKay Creek, Ochoco Creek, the Crooked River (including relict channels), and wetlands. Metrics are not reported twice for this project given co-funding from OWEB.

Both spring Chinook salmon and summer steelhead use each of the three streams flowing through Ochoco Preserve. The specific purpose of the restoration design will be to support restoration actions that will address limiting factors to increase the quality and quantity of habitat in these reaches. We expect these actions to include the following:

1. Add Large Wood (McKay and Ochoco Creeks). Many studies have found a strong association between large wood and salmon productivity. Large wood is important not only in forming pools, but in providing cover for holding and spawning adults, and for both fry and parr. Large wood and log jams also provide slow-water areas for juvenile fish, create gravel beds for spawning, and increase food availability by trapping nutrients and providing surfaces for algae growth.

2. Increase Pools (McKay Creek emphasis). This could mean adding habitat features to the existing channel, removing streamside levees, and/or actively re-establishing sinuosity and floodplain connectivity. Whatever the extent and magnitude of restoration, a central goal will be to increase the number and quality of pools in the reach. The existing reach includes only one pool 1m deep and one complex pool (>3 LWD). Many studies establish a strong correlation between quality pool habitat and salmon production, particularly as it relates to spawning and parr performance. Providing pools with additional depth may also be important for adult holding. Lower McKay Creek, because it is used to transport Ochoco Irrigation District water, is cool relative to the Crooked River during summer and early fall. Providing holding habitat in this lowermost reach and confluence area could benefit adult salmon that will ultimately move further upstream in the Crooked River or into Ochoco Creek.

3. Restore Riparian Vegetation (Site-wide). Restore willows and other site-appropriate native hardwoods throughout the site. This will benefit salmon and steelhead in the following ways:

a. Provide cover. Numerous studies demonstrate a strong association between salmon and cover at all life stages.
b. Help maintain cool water temperatures by providing shade and creating cool and humid microclimates over the stream.
c. Provide food resources for the aquatic ecosystem including leaves, branches, and terrestrial insects.
d. Provide better habitat for beaver. Several recent studies suggest a correlation between beaver presence and increased salmon productivity.

4. Provide Side Channel Habitat (McKay Creek, Ochoco Creek, Crooked River). These slow water habitats—characterized by fine substrates and abundant vegetation—are critical for the survival of Chinook salmon fry and overwintering parr.

5. Restore Complexity to the McKay and Ochoco Confluences. In summer months both McKay and Ochoco creeks are cool relative to the Crooked River. Restoring complexity to these confluences will provide a range of benefits to Chinook salmon, from enhanced adult holding habitat to more secure and productive fry habitat.

6. Increase Floodplain Interaction and Restore Historic Wetlands. Large areas of the property sit low relative to the Crooked River and McKay Creek. Both streams are held back by berms, but still flood portions of the property regularly. We plan to remove these berms and return these low areas to floodplain and wetland environments. Floodplains and wetlands provide direct habitat and nutrient benefits to Chinook salmon fry and parr, and the capture of flood flows and reestablishment of hyporheic interaction can have significant benefits to water quality.