The Confederated Tribes of the Umatilla Indian Reservation (CTUIR), in cooperation with project partners Bureau of Reclamation (BOR), USDA Forest Service, Wallowa-Whitman National Forest – La Grande Ranger District (USFS), Grande Ronde Model Watershed (GRMW), and Bonneville Power Administration (BPA), propose implementation of floodplain and riverine restoration using CTUIR’s River Vision to restore fluvial processes and ecological functions that support cold water fishery resources.

The Longley Meadows Fish Habitat Enhancement Project is located in the Upper Grande Ronde Subbasin, on the Grande Ronde River, between about RM 144.7 and RM 142.1. The Project reach sits at an elevation of approximately 3,100 feet and with contributing watershed area of 475 mi2, which is predominantly snowmelt-driven. Most of the basin is forested (over 73 percent) and has very little development (less than 0.1 percent estimated impervious area) (USGS 2014). The Project reach includes Wallowa-Whitman National Forest and private lands along State Highway 244 within the Grande Ronde recovery plan assessment units UGC3A and UGS16. The Upper Grande Ronde River Tributary Assessment identifies the Project reach as an unconfined geomorphic reach with a high potential to improve the overall physical and ecological processes that support salmonids in the basin.

Fish habitat suitability within the Project reach has been significantly affected and suppressed by physical alterations of the river and its associated floodplain (splash dam logging, mining, and road construction) that have contributed to severely degraded habitat conditions. Problems include homogenous, high energy, plane bed riffle-run channel types with a lack of large pool habitat, channel complexity, peripheral habitat bed armoring and alteration of sediment sorting and coarsening of streambed gravel, altered groundwater and hyporheic function, and degradation of riparian and wetland plant communities.

Natural habitat recovery is limited by current environmental conditions that suppress development of diverse hydrologic and geomorphic processes, including an armored streambed, lack of mature riparian vegetation and associated complexity/wood loading, and lack of significant floodplain activation/connection.

Core habitat suitability limiting factors affecting juvenile summer and winter rearing and adult holding and migration include: water quality (temperature), channel and bed form and complexity (limited low velocity and large pool habitat), riparian conditions, and sediment.

The long-term rehabilitation vision (CTUIR’s River Vision) for the Bird Track Springs Fish Habitat Enhancement Project is to improve physical and ecological processes by rehabilitating and restoring the project area to achieve immediate and long-term benefits to chinook, steelhead, and bull trout at all life stages.

The restoration plan includes promoting an island braided channel and floodplain system through channel, floodplain, and large pool construction, development of riparian and wetland habitat, and promoting groundwater and hyporheic functions that moderate and improve water quality. A fundamental premise is that self-sustaining, high quality, and diverse habitat provides habitat suitability for all life stages of target fishery resources.

Objectives

1.    Increase habitat diversity and complexity for salmonids

•    LWM - Maximize large wood material density within wetted channels of project reach within confines of geomorphic and physical context of project site with consideration of risk to existing infrastructure. Wood loading objective is to exceed 80 large pieces of wood per stream mile.
•    Pools - Develop 12 sustainable and complex pools per mile for fish use (adult holding and juvenile rearing) at completion of project.
•    Side Channels – Maximize and promote ephemeral and perennial side channels that include complex cover and perennial alcove features within the hydrogeomorphic conditions/constraints of the project area at project completion. Increase side channel habitat by more than twice the length of main channel habitats (10,400 LF and 4,900 LF, respectively).
•    Bedload Retention/Sorting – Improve instream channel diversity within the project reach changing the predominant plane-bed channel conditions associated with homogenous particle size retention to a pool-riffle channel with greater particle size diversity. Increased particle size diversity objective will be monitored utilizing Woleman pebble count surveys and compared to pre-project baseline data.
•    Alcoves and Off Channel Ponds - Maximize off-channel features such as alcove and off-channel pond habitats with preferred depth, velocity, and cover for refuge and rearing of juvenile Chinook. Increase alcove habitat by at least 150 linear feet, and increase floodplain swale connections by at least 1,000 linear feet after project completion.
•    Beaver – Establish side channel conditions and floodplain vegetative health that will increase suitable beaver habitat within the project area within 10 years of project completion. Beaver habitat suitability defined by amount of off-channel habitat (side channels and alcoves) and riparian/wetland habitat (hardwood and shrub for winter food supply and sedge/herbaceous for general food supply). Increase stem density in riparian and floodplain areas by 700 plants per acre with supplemental plantings within one year after project completion.

2.    Improve water temperature conditions for salmonids

•    Thermal Loading:  At project completion, have no net increase in thermal loading in as-built baseflow main channel wetted surface area through decreasing width-to-depth ratio during base flow conditions.  Provide long term decrease in baseflow water surface exposed to solar radiation within project area through increased shading from native riparian plants and a net decrease in width-to-depth ratio.
•    Thermal Diversity:  Channel Sinuosity – Improve thermal diversity at baseflow conditions by increasing hyporheic conductivity pathways by maximizing sinuosity of the main channel alignment within site geomorphic constraints/conditions. Increase main channel sinuosity by increasing current channel by a net gain of at least 800 linear feet.  Increase Water Table – Improve cool water supply and thermal diversity potential within the project area by increasing water storage within the floodplain through increased annual and low flow water table elevation at the completion of the project. Wells containing piezometers installed throughout project area floodplain will be used to monitor increased groundwater elevation objective.
•    Connection to Cold Water Sources:  Improve thermal diversity during baseflow conditions by identifying and connecting the main channel to potential cold water sources of hyporheic and/or groundwater sources including historic relic channels and preferential sub-surface flow paths. Increase suitable micro-habitat connections with main channel, and increase number of annual hours that mean daily temperatures are recorded within preferred range of 10 – 15.6C at these locations.  
•   Bedload Sediment Retention:  Improve thermal diversity at baseflow conditions by promoting channel bed diversity resulting in reduction of bed armor, improved bedload sediment retention, vertical gradients, and sediment storage to create dynamic depositional features with increased and improved hyporheic connectivity.  Increased channel bed diversity objective will be monitored utilizing Woleman pebble count surveys and compared to pre-project baseline data.

3.    Improve riparian corridor and floodplain vegetative diversity and health within the project area

•    Floodplain Connectivity - Maximize floodplain connectivity within the geomorphic and stakeholder confines of the project area. Activate the floodplain on an annual basis during the spring freshet and increase floodplain acres inundated at all flow conditions greater than base flow after project completion, including 50% increase in inundated acres at bankfull.
•    Woody Riparian Vegetation – Increase native woody vegetation stem density by 700 plants per acre by supplemental planting within one year after project completion, including dominant cottonwood, alder, and willows within the limitations of soil structure and hydrology within the project reach to maximize shade on water surfaces 10-years following project completion.
•    Suspended Sediment Retention – Improve suspended sediment retention on floodplain surfaces within the project area by increasing floodplain acres inundated at all flow conditions greater than base flow, and increasing number of floodplain roughness features by at least 135 after project completion.
•    Prevent the establishment  and see no net gain of non-native weeds within the project boundary for first 5-years after construction through active weed management.

4.    Reconnect the Grande Ronde River with its floodplain and expand quality floodplain habitat availability for salmonids within the project boundaries

•    Construct a new channel network that allows floodplain interaction with river flows at a minimum of an annual basis during spring high flow conditions and increase floodplain acres inundated at all flow conditions greater than base flow after project completion, including 50% increase in inundated acres during bankfull events.