Shadow Cliffs Regional Recreation Area is a

regional park A regional park is an area of land preserved on account of its natural beauty, historic interest, recreational use or other reason, and under the administration of a form of local government. Definition A regional park can be a special park distri ...

on the border of

Pleasanton Pleasanton may refer to: Places * Pleasanton, California * Pleasanton, Iowa * Pleasanton, Kansas * Pleasanton, Nebraska * Pleasanton, New Mexico * Pleasanton, Ohio * Pleasanton, Texas * Pleasanton Township, Michigan Other * Pleasanton High School ...

and

Livermore, California Livermore (formerly Livermorès, Livermore Ranch, and Nottingham) is a city in Alameda County, California. With a 2020 population of 87,955, Livermore is the most populous city in the Tri-Valley. It is located on the eastern edge of Californ ...

, that is part of the East Bay Regional Parks (EBRP) system. Its lake, once a gravel pit, has a sandy beach and is used for swimming, fishing, and recreational boating. The park once featured water slides, which were closed in 2011 and have since been taken down, and are planned to be replaced by an Interpretive Center. The park is also a popular picnic ground.

History

Shadow Cliffs, a former gravel quarry, was donated to EBRP by

Kaiser Industries ''Kaiser'' is the German word for "emperor" (female Kaiserin). In general, the German title in principle applies to rulers anywhere in the world above the rank of king (''König''). In English, the (untranslated) word ''Kaiser'' is mainly ap ...

, the former operator of the quarry, and opened as a park in 1971. The U.S. Bureau of Outdoor Recreation provided a grant of $250,000 for development of park facilities. Thus funded, EBRPD developed a park that included an lake, picnic facilities and large parking lot."Shadow Cliffs Regional Recreation Area." East Bay Regional Park District.
Accessed August 14, 2017.

Activities

Swimming

Swimming is allowed year-round at the swimmer's own risk, although lifeguards are on duty during the summer. The swimming beach on the main lake and a refreshment stand are open on weekends in spring and fall and daily in summer. Pets and glass containers are not allowed on the sandy areas of the beach. Beach wheelchairs are available at no charge on a first-come, first-served basis.

Fishing

Fishing is allowed in the main lake, provided the angler has a Park District Daily Fishing Access Permit. Trout and catfish are planted every week by park personnel. Other species popular with anglers are bluegill and black bass. The

California Office of Environmental Health Hazard Assessment The Office of Environmental Health Hazard Assessment, commonly referred to as OEHHA (pronounced oh-EEE-ha), is a specialized department within the cabinet-level California Environmental Protection Agency ( CalEPA) with responsibility for evaluatin ...

(OEHHA) has developed a safe eating advisory for fish caught in the Shadow Cliffs Regional Recreation Area based on levels of mercury or

PCBs Polychlorinated biphenyls (PCBs) are highly carcinogenic chemical compounds, formerly used in industrial and consumer products, whose production was banned in the United States by the Toxic Substances Control Act in 1979 and internationally by t ...

found in local species.

''E. coli''

Lake water at Shadow Cliffs Beach is tested for bacterial levels weekly during April through October and twice a month from November to March. In July 2014, EBRP closed the lake to swimmers due to extremely high levels of ''

E. coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...

'' bacteria. Testing of water samples demonstrated ''E. coli'' at 6,100 colonies per 100 milliliters at the lake's south beach and 1,000 colonies per 100 milliliters at the north beach. California's state standard for daily maximum exposure is 235 colonies per 100 milliliters. Hal MacLean, the district water management supervisor, suggested that a combination of drought conditions, low water levels and accumulated animal feces—probably from geese—had caused the high bacterial content. EBRP planned to treat the lake with an

oxidizing agent An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or "Electron acceptor, accepts"/"receives" an electron from a (called the , , or ). In ot ...

and "direct geese away from the swim area" in an attempt to lower the levels.

Quagga mussel inspections

As of October 2016, EBRPD requires that all motorized and paddle boats entering Shadow Cliffs Lake be inspected for

quagga mussel The quagga mussel (''Dreissena rostriformis'', also known as ''Dreissena bugensis'' or ''Dreissena rostriformis bugensis'') is a species (or subspecies) of freshwater mussel, an aquatic bivalve mollusk in the family Dreissenidae. It has an aver ...

s. The district charges owners a $7.00 fee to inspect motorized boats, and $3.00 to inspect inflatables, kayaks, canoes, and other vessels carried on top of cars entering Shadow Cliffs Regional Recreation Area.Cuff, Denis. "Pleasanton lake to require boat inspections for mussels." ''East Bay Times''. September 8, 2016.
Accessed September 6, 2017.

References

External links

Ebparks.org: official Shadow Cliffs Regional Recreation Area website
{{coord, 37, 40, 10, N, 121, 50, 22, W, display=title East Bay Regional Park District Parks in Alameda County, California Livermore Valley Geography of Pleasanton, California Livermore, California Protected areas established in 1971 1971 establishments in California