Biological Opinions - Bureau of Reclamation

Riparian restoration projects will increase stream shading and instream cover habitat for rearing
juveniles, moderate stream temperatures, and improve water quality through pollutant filtering.
Beneficial effects of constructing livestock exclusionary fencing in or near streams include the
rapid regrowth of grasses, shrubs, and other vegetation released from overgrazing, and reduced
nitrogen, phosphorous, and sediment loading into the stream environment (Line et al. 2000;
Brenner and Brenner 1998). Further, Owens et al. (1996) found that stream fencing has proven
to be an effective means of maintaining appropriate levels of sediment in the streambed.
Another documented, beneficial, long-term effect is the reduction in bankfull width of the active
channel and the subsequent increase in pool area in streams (Magilligan and McDowell 1997).
All will contribute to a more properly functioning ecosystem for listed species by providing
additional spawning and cover habitat relative to their current condition.
2. Water Conservation
Implementing water conservation measures will wholly benefit coho salmon by returning some
flow to the stream at a time when coho salmon require adequate habitat to rear and migrate.
Increasing instream flow levels by diminishing water diversions will provide juvenile coho
salmon with better access to suitable rearing and spawning habitat, especially during the summer
and early fall when flows are lowest. Water conservation projects are most likely to occur in the
tributaries, such as the Shasta and Scott rivers. Therefore, short-term restoration of flows are
expected to affect only the tributaries because the next priority water right user or riparian water
right user is likely to divert those flows and water conserved at the restoration site is likely to
increase instream flows in a relatively small reach of these tributaries.
Installing water measuring devices will likely result in discountable or insignificant effects to
listed species because these activities typically occur in diversion ditches where increased
mobilization of sediment is unlikely to reach the stream channel. Construction of tail water
ponds will improve water quality by minimizing the return of warm, nutrient rich water into the
river.
Therefore, the following components of the proposed restoration actions are expected to result in
insignificant, discountable, or wholly beneficial effects to coho salmon and their designated
critical habitat relative to existing conditions: riparian habitat restoration, development of
alternative stockwater supply, tailwater collection ponds, water storage tanks, and piping ditches.
Some components of the restoration activities also may result in effects, such as temporary
instream habitat disturbance from heavy equipment operation, riparian vegetation disturbance,
chemical contamination, and reduced benthic macroinvertebrate production that are not likely to
adversely affect listed species or their critical habitats. These effects are expected to be
insignificant or discountable as explained further below.
11.4.2.1.1 Spawning Habitat
Spawning habitat is not likely to be adversely affected by the temporary increase in fine
sediment resulting from the proposed restoration activities. Spawning habitat is located where
water velocities are higher, where mobilized fine sediment is less likely to settle. Where limited
280