Final Mitigated Negative Declaration and Response to Comments

CHAPTER 2
PROJECT DESCRIPTION
2.1 INTRODUCTION
This Initial Study/Mitigated Negative Declaration (IS/MND) has been prepared by the
California Department of Parks and Recreation (DPR) to evaluate the potential
environmental effects of the proposed Asian Clam Control Project at Emerald Bay State
Park, located in El Dorado County, California. The proposed project would control a
population of invasive Asian clams near the mouth of Emerald Bay (see map: Appendix
A).
2.2 PROJECT LOCATION
Lake Tahoe is a large, high elevation (approximately 6,223 ft.) lake in the Sierra Nevada
Mountains. The lake sits in a basin encompassed by the Crystal Range to the west and
the Carson Range to the east. The border between California and Nevada divides the
lake. Lake Tahoe Basin is approximately 20 miles southwest of Reno, Nevada and
approximately 80 miles northeast of Sacramento, California.
Emerald Bay State Park (SP) is located around Emerald Bay, a National Natural
Landmark since 1968. It is immediately south and contiguous with D. L. Bliss SP. The
park contains the only island in Lake Tahoe- Fannette Island. In 1994, DPR included
the surrounding water of the bay as a part of the park, making Emerald Bay SP one of
the first underwater parks of its type in the state. The underwater park is managed by
DPR under a lease from the California State Lands Commission. The park is
accessible by State Route 89 near the southwest shore of the lake. The unit is 663 land
acres in size, with the underwater area of Emerald Bay covering an additional 870
acres. There is approximately 14,130 feet of shoreline along Lake Tahoe.
2.3 BACKGROUND AND NEED FOR THE PROJECT
Asian clam (Corbicula fluminea; AC) were first documented in Lake Tahoe in 2002 (U.C.
Davis 2009; Whittmann et al. 2011). Since the initial AC detection, the populations in
South Lake Tahoe increased rapidly from 1 to nearly 200 acres in less than 10 years
with densities up to 6,000 individuals per square meter measured (U.C. Davis 2010). A
relatively sparse population was discovered near the mouth of Emerald Bay in 2009.
Initial surveys estimated this infestation at approximately 3.5 acres in size just inside
and on the south side of the mouth of Emerald Bay, in water depths of 6 to 30 feet (see
map: Appendix A). Surveys in 2011 showed the infestation had spread to
approximately 5.5 acres (2011 U.C. Davis Survey Results; see Appendix A), an
increase in infestation size of over 40% in only two years. An expansion of the Emerald
Bay infestation similar to that seen in South Lake Tahoe would result in considerable
ecological and recreation impacts.
Asian Clam Control Project IS/MND
Emerald Bay State Park
California Department of Parks and Recreation
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