Lake Del Valle

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page lists two swimming beaches, lifeguards during posted periods, boat rentals, and a public launch for boats of any size; it warns that boaters must comply with the Invasive Mussel Prevention Program and mandatory inspections.

   Publisher

   ReserveAmerica / East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: ReserveAmerica / East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   At retrieval, the page stated that a boat launched at Contra Loma would be quarantined for 30 days from inspected lakes including Del Valle; vessels must be cleaned, drained, and dried, and boat bands are honored only by the lake that issued them. It also requires campground guests with watercraft to complete inspection before campground check-in.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   2026-09-20T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

3. Evidence stance: supports · Evidence details

   EBRPD requires watercraft inspection at Contra Loma, Del Valle, Lake Chabot, Quarry Lakes, and Shadow Cliffs. Covered craft include boats, kayaks, canoes, sailboats, inflatable craft, and every form of floating board. Campers with watercraft must complete inspection before campground check-in.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

Claim effective interval: 2023-09-01 to No end bound

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Sections 501.2 and 503.4-503.9 allow car-top and trailered boats at Del Valle without size restriction; limit use to sunrise-sunset or posted hours; cap gasoline-powered boats at 10 mph; prohibit towing people and fuel/oil pollution; and regulate proximity to swim areas and swimmers.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   2023-09-01T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

   Recorded artifact references

   • PDF pages 16, 18-19

   References are not a confirmation of current availability.

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page lists launch and inspection fees of $5 and $10 for motorized vessels and $3 and $5 for non-motorized vessels, a lake-wide 10 mph speed limit, and a prohibition on hydrofoils and E-Foils. It permits any-size boats at the public ramp.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

Claim effective interval: 2023-09-01 to No end bound

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Sections 501.2 and 503.4-503.9 allow car-top and trailered boats at Del Valle without size restriction; limit use to sunrise-sunset or posted hours; cap gasoline-powered boats at 10 mph; prohibit towing people and fuel/oil pollution; and regulate proximity to swim areas and swimmers.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   2023-09-01T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

   Recorded artifact references

   • PDF pages 16, 18-19

   References are not a confirmation of current availability.

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page lists launch and inspection fees of $5 and $10 for motorized vessels and $3 and $5 for non-motorized vessels, a lake-wide 10 mph speed limit, and a prohibition on hydrofoils and E-Foils. It permits any-size boats at the public ramp.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   Evidence notes: Section 503.6(a).

   Sections 501.2 and 503.4-503.9 allow car-top and trailered boats at Del Valle without size restriction; limit use to sunrise-sunset or posted hours; cap gasoline-powered boats at 10 mph; prohibit towing people and fuel/oil pollution; and regulate proximity to swim areas and swimmers.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   2023-09-01T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

   Recorded artifact references

   • PDF pages 16, 18-19

   References are not a confirmation of current availability.

Claim effective interval: 2026-09-20 to 2026-09-20

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   At retrieval, the page stated that a boat launched at Contra Loma would be quarantined for 30 days from inspected lakes including Del Valle; vessels must be cleaned, drained, and dried, and boat bands are honored only by the lake that issued them. It also requires campground guests with watercraft to complete inspection before campground check-in.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   2026-09-20T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   The current notice reports golden mussels at Contra Loma and states that a boat launched there is quarantined for 30 days from inspected lakes including Del Valle. All vessels should be cleaned, drained, and dried, and bands are honored only at their issuing lake.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   2026-09-20T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

Claim effective interval: 2023-09-01 to No end bound

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Sections 801.1-801.3 prohibit dog swimming at Lake Del Valle from Oak Point north to the East Marina; require leashes in developed areas including campgrounds; cap leashes at six feet and dogs at three per person; and require campground animals to be attended and leashed or confined.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   2023-09-01T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

   Recorded artifact references

   • PDF pages 25-27

   References are not a confirmation of current availability.

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   EBRPD reports regular lake and shoreline monitoring with warnings and closures posted when appropriate. Drinking water from the Del Valle treatment plant is regularly tested for effects from reservoir blooms.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

Claim effective interval: 2023-09-01 to No end bound

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Sections 501.2 and 503.4-503.9 allow car-top and trailered boats at Del Valle without size restriction; limit use to sunrise-sunset or posted hours; cap gasoline-powered boats at 10 mph; prohibit towing people and fuel/oil pollution; and regulate proximity to swim areas and swimmers.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   2023-09-01T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

   Recorded artifact references

   • PDF pages 16, 18-19

   References are not a confirmation of current availability.

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page lists launch and inspection fees of $5 and $10 for motorized vessels and $3 and $5 for non-motorized vessels, a lake-wide 10 mph speed limit, and a prohibition on hydrofoils and E-Foils. It permits any-size boats at the public ramp.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page lists two swimming beaches, lifeguards during posted periods, boat rentals, and a public launch for boats of any size; it warns that boaters must comply with the Invasive Mussel Prevention Program and mandatory inspections.

   Publisher

   ReserveAmerica / East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: ReserveAmerica / East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page advises keeping water out of the mouth, showering and towel-drying promptly after swimming, avoiding lake swimming for three days after rain, checking posted water-quality signs, and keeping dogs away from the water.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The Del Valle swimming page lists lifeguards 11 AM-6 PM on weekends and holidays from May 16 through September 27, two beaches, and year-round swimming without lifeguards north of the boat ramp.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

Claim effective interval: 2026-09-20 to 2026-09-20

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   At retrieval, the page stated that a boat launched at Contra Loma would be quarantined for 30 days from inspected lakes including Del Valle; vessels must be cleaned, drained, and dried, and boat bands are honored only by the lake that issued them. It also requires campground guests with watercraft to complete inspection before campground check-in.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   2026-09-20T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   The current notice reports golden mussels at Contra Loma and states that a boat launched there is quarantined for 30 days from inspected lakes including Del Valle. All vessels should be cleaned, drained, and dried, and bands are honored only at their issuing lake.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   2026-09-20T00:00:00+00:00

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Del Valle beaches are sampled for bacteria weekly April-October and twice monthly November-March, with two sample sites per beach. Posted stop-light signs combine latest bacteriological tests and blue-green algae conditions.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   EBRPD routinely monitors recreational and drinking water, storm water, wastewater, lakes and creeks, and responds to sewage, oil, and hazardous-material incidents. Natural swim areas are sampled weekly April-October in collaboration with county environmental-health departments, with current data posted for safe recreation choices.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The District lists Del Valle among waters stocked with rainbow trout from fall through spring and channel catfish in summer, and manages other gamefish including bass, bluegill, sunfish, and crappie.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   Anglers age 16 or older need a California fishing license for eligible District inland waters and a District fishing permit unless fishing at one of four named exceptions; Del Valle is not an exception. Current alerts should be checked.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   Wayproof source review

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page identifies Del Valle Regional Park as an East Bay Regional Park District park about ten miles south of Livermore, with a 4,316-acre park around a five-mile-long lake; it lists 7000 Del Valle Road, Livermore, California 94550 and coordinates 37.56917, -121.68722.

   Publisher

   ReserveAmerica / East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: ReserveAmerica / East Bay Regional Park District

No claim effective interval recorded.

Spatial scope IDs: scope-lake-del-valle

1. Evidence stance: supports · Evidence details

   The page identifies Del Valle Regional Park as an East Bay Regional Park District park about ten miles south of Livermore, with a 4,316-acre park around a five-mile-long lake; it lists 7000 Del Valle Road, Livermore, California 94550 and coordinates 37.56917, -121.68722.

   Publisher

   ReserveAmerica / East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: ReserveAmerica / East Bay Regional Park District

2. Evidence stance: supports · Evidence details

   The EBRPD page places Del Valle ten miles south of Livermore, describes a five-mile lake in a 4,395-acre park, gives the address 7000 Del Valle Road, and calls the park the eastern gateway to the 28-mile Ohlone Wilderness Trail.

   Publisher

   East Bay Regional Park District

   Observer / attribution

   user-supplied page transcription

   Observed at

   Unknown

   Retrieved at

   2026-09-20T00:00:00+00:00

   Retrieval time does not establish when an event occurred.

   Observation details · Source details · Original source: East Bay Regional Park District