EBRPD Harmful Algal Bloom Monitoring Program

Monitoring program

Plan with 10 source-backed facts, 0 related records, and explicit uncertainty.

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Requirements and current conditions

Advisory fish guidance

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

Avoid unnecessary water contact
Yes
Cook thoroughly
Yes
Discard guts and liver
Yes
Wash fillet with safe water
Yes
Wash hands after wet contact
Yes
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    During an algae advisory, EBRPD advises avoiding unnecessary water contact and washing hands after handling fish or wet equipment. Fish fillets should be washed with tap or bottled water, guts and liver discarded, and fish cooked thoroughly. Reservoir fish are tested annually; at retrieval the page reported no microcystin detected to date in fish flesh from District-managed waters.

    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

Bloom conditions

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

  • low water
  • limited circulation
  • increased temperature
  • increased light
  • low oxygen
  • high phosphorus
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    Blue-green algae are cyanobacteria. Low water, limited circulation, increased temperature and light, low oxygen, and high phosphorus can favor blooms and potential toxin release; toxin production remains incompletely understood.

    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

Facilities and services

Dog exposure risk

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

High susceptibility
Yes
Routes
  • drinking
  • swimming
  • wading
  • grooming fur or paws
  • eating dried shoreline algae
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    Exposure to toxic algae by ingestion, inhalation, or skin contact can cause rashes, eye or skin irritation, allergic reactions, breathing difficulty or congestion, gastrointestinal illness, and in high exposures serious illness or death. Dogs face special risk from drinking, swimming, wading, grooming contaminated fur or paws, or eating dried shoreline algae.

    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

Optional swim registration

Recorded for: East Bay Regional Park District

Named facilities
  • Castle Rock/Diablo Foothills
  • Cull Canyon
  • Don Castro
Pass hours
  • 11:00
  • 18:00
People per registration
5
Price usd
6
Refundable
No
Transferable
No
Water exit
17:30
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    EBRPD describes six lakefront beaches, two chlorinated lagoons, two pools, and two bay beaches. Walk-ins at open facilities are first-come until capacity. Optional weekend/holiday registration is named only for Castle Rock/Diablo Foothills, Cull Canyon, and Don Castro; registered sessions cost $6 per person, limit each registration to five entrants, and run 11 AM-6 PM with water exit at 5:30 PM.

    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

Water quality program scope

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

  • recreational water
  • drinking water
  • storm water
  • wastewater
  • lakes
  • creeks
  • water related emergencies
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. 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

More planning facts

Bacterial stoplight meanings

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

Green
indicator results below maximums meet state standards
Indicators
  • total coliform
  • fecal coliform
  • Enterococcus
  • E coli
Red
beach closed for water quality issue
Yellow
one or more indicators exceed daily maximum
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    California swim-water evaluation uses total coliform, fecal coliform, Enterococcus, and E. coli indicators. Green means results are below maximums and meet state standards; yellow means one or more indicators exceeds a daily maximum; red means the beach is closed for a water-quality issue and visitors must not enter.

    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

Del valle beach monitoring

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

April october
weekly
November march
twice monthly
Sample sites per beach
2
Sign inputs
  • bacteria
  • blue green algae
Evidence and sources (2)

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

Human exposure risk

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

Effects
  • rash
  • skin eye irritation
  • allergic reaction
  • breathing difficulty
  • congestion
  • gastrointestinal illness
  • serious illness
  • death
Routes
  • ingestion
  • inhalation
  • skin contact
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    Exposure to toxic algae by ingestion, inhalation, or skin contact can cause rashes, eye or skin irritation, allergic reactions, breathing difficulty or congestion, gastrointestinal illness, and in high exposures serious illness or death. Dogs face special risk from drinking, swimming, wading, grooming contaminated fur or paws, or eating dried shoreline algae.

    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

Monitoring practice

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

Lakes and shorelines
regular
Posts warnings and closures
Yes
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  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

Published fish testing result

Recorded for: EBRPD Harmful Algal Bloom Monitoring Program

Frequency
annual
Microcystin in flesh detected to date
No
Evidence and sources (1)

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

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    During an algae advisory, EBRPD advises avoiding unnecessary water contact and washing hands after handling fish or wet equipment. Fish fillets should be washed with tap or bottled water, guts and liver discarded, and fish cooked thoroughly. Reservoir fish are tested annually; at retrieval the page reported no microcystin detected to date in fish flesh from District-managed waters.

    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

Explore related places

No related canonical records are published yet.

Before you go

These open questions need confirmation; Wayproof does not fill them with guesses.

Which activities are allowed or prohibited at each EBRPD algae advisory level?

This page gives general health guidance but does not define the operational rules for Caution versus Danger; the linked beach-conditions material is still needed.

Open question. Linked evidence does not resolve this gap.

Swimming advisory

caution
Evidence and sources (4)

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

Spatial scope IDs: scope-del-valle-east-beach

  1. Evidence stance: supports · Evidence details

    At retrieval, the EBRPD page posted a blue-green algae Caution Advisory for the East Swim Beach and stated that the West Swim Beach had no water because of low lake levels.

    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

    At retrieval, the current-conditions table listed a Caution Advisory for the Del Valle East Swim Beach and no advisory for the West Swim Beach, where it reported no water because of low lake levels.

    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

    At retrieval, East Beach had a blue-green algae Caution Advisory and West Beach had no water because of low lake levels.

    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

  4. Evidence stance: supports · Evidence details

    At retrieval, the table listed a Caution algae advisory at Del Valle East Beach and no advisory at West Beach, where there was no water because of low lake levels.

    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

Advisory fish guidance

Avoid unnecessary water contact
Yes
Cook thoroughly
Yes
Discard guts and liver
Yes
Wash fillet with safe water
Yes
Wash hands after wet contact
Yes
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    During an algae advisory, EBRPD advises avoiding unnecessary water contact and washing hands after handling fish or wet equipment. Fish fillets should be washed with tap or bottled water, guts and liver discarded, and fish cooked thoroughly. Reservoir fish are tested annually; at retrieval the page reported no microcystin detected to date in fish flesh from District-managed waters.

    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

Dog exposure risk

High susceptibility
Yes
Routes
  • drinking
  • swimming
  • wading
  • grooming fur or paws
  • eating dried shoreline algae
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    Exposure to toxic algae by ingestion, inhalation, or skin contact can cause rashes, eye or skin irritation, allergic reactions, breathing difficulty or congestion, gastrointestinal illness, and in high exposures serious illness or death. Dogs face special risk from drinking, swimming, wading, grooming contaminated fur or paws, or eating dried shoreline algae.

    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

Human exposure risk

Effects
  • rash
  • skin eye irritation
  • allergic reaction
  • breathing difficulty
  • congestion
  • gastrointestinal illness
  • serious illness
  • death
Routes
  • ingestion
  • inhalation
  • skin contact
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    Exposure to toxic algae by ingestion, inhalation, or skin contact can cause rashes, eye or skin irritation, allergic reactions, breathing difficulty or congestion, gastrointestinal illness, and in high exposures serious illness or death. Dogs face special risk from drinking, swimming, wading, grooming contaminated fur or paws, or eating dried shoreline algae.

    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

How do Del Valle algae advisory levels combine with the now-defined bacterial traffic-light designation?

Green/yellow/red bacterial meanings are now defined, but the source does not explain how a simultaneous algae Caution or Danger changes allowed activities.

Open question. Linked evidence does not resolve this gap.

Bacterial stoplight meanings

Green
indicator results below maximums meet state standards
Indicators
  • total coliform
  • fecal coliform
  • Enterococcus
  • E coli
Red
beach closed for water quality issue
Yellow
one or more indicators exceed daily maximum
Evidence and sources (1)

No claim effective interval recorded.

Spatial scope IDs: scope-ebrpd-water-quality-program

  1. Evidence stance: supports · Evidence details

    California swim-water evaluation uses total coliform, fecal coliform, Enterococcus, and E. coli indicators. Green means results are below maximums and meet state standards; yellow means one or more indicators exceeds a daily maximum; red means the beach is closed for a water-quality issue and visitors must not enter.

    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

Sources, evidence, and history

Planning facts above are readable first. Open these records when you need to audit a source or see when knowledge changed.

Evidence for 10 published claims
Published ChangeSet history

Canonical data is historical evidence, not a guarantee of current conditions. Recheck volatile facts before travel.