Draft EIS_072312.pdf - Middle Fork American River Project ...

20120723-4002 FERC PDF (Unofficial) 07/23/2012
there is an established nexus of existing populations of this algae in project waters to
project operations or facilities.
PCWA’s publically available Invasive Mussel Protection Plan (2010a) concluded
that the project has a low level of vulnerability to the introduction of invasive mussels
based on its geographic location, recreational uses, and water quality. Calcium
concentrations within the reservoirs average 3.1 milligrams per liter (mg/L), which is
lower than the 15 mg/L threshold below which poor zebra and quagga mussel health and
population growth have been documented. Effects of low calcium levels on these
invasive mussels include low growth rates, shell degradation, and poor larval production
(California Resources Agency, 2008, as cited in PCWA, 2010a). PCWA’s plan includes
the following measures: (1) public education on how to minimize transfer of invasive
mussels into project waters, (2) annual monitoring, and (3) a rapid response plan, to be
developed in consultation with California Fish and Game in the event that one of these
species is documented. We conclude that these measures would minimize potential
invasions and associated effects on aquatic communities in project-affected waters.
However, we note that the Commission has authority over hydropower licensees. The
Invasive Mussel Protection Plan referenced in the VIPMP would by such reference
become part of the VIPMP. Therefore, the Commission would be able to enforce
compliance with both the approved VIPMP and the Invasive Mussel Protection Plan.
3.3.2.3 Cumulative Effects
Water Quantity
Flows passing through the project are described in section 3.3.2.1 and shown in
tables 3.3.2-3 and 3.3.2-5. As shown in figure 2, the amount of water entering the project
via the Rubicon and South Fork Rubicon River is heavily influenced by operations of
Sacramento Municipal Utility District’s Upper American River Project (FERC No. 2101)
and Georgetown Divide Public Utility District’s Stumpy Meadows Project (a non-FERC
regulated project). In addition, flows downstream of Oxbow powerhouse are influenced
by the following non-project facilities: (1) Foresthill Public Utility District’s Sugar Pine
Dam Project, which diverts flow from a tributary to the North Fork American River for
consumptive use; (2) Pacific Gas and Electric Company’s Drum-Spaulding Project
(FERC No. 2310), which diverts flows for hydroelectric generation from two tributaries
to the North Fork American River; (3) PCWA’s Pulp Mill Canal Diversion Dam Project,
which diverts flows for consumptive use from a tributary to the North Fork American
River; and (4) PCWA’s American River Pump Station, which diverts water from the
North Fork American River for consumptive use. Operation of each of these projects is
expected to be similar in the future compared to current operations with the possible
exception of the Drum-Spaulding Project, which is in the midst of relicensing.
PCWA modeled the cumulative effect of all these flow-related projects, including
the Middle Fork Project, on inflow to Folsom reservoir. Compared to the hypothetical
unregulated watershed upstream of Folsom reservoir, flows entering the reservoir during
128