≡ Categories

ALERT: Restore the Delta is sharing this message from the California Regional Water Quality Control Board, Central Valley.

Cyanobacteria Bloom-Central Delta 7/28/20

Good Afternoon, 

Central Valley Water Board staff has observed moderate cyanobacteria blooms in various Delta locations during routine recreational water quality monitoring activities. Cyanobacteria water samples were collected at five locations on 7/16/20 and sent to Bend Genetics for lab analysis. 

Incident Details:    

  • Moderate cyanobacteria HABs throughout the San Joaquin River, Disappointment Slough and Honker Cut.  
  • Two cyanobacteria genera (Microcystis and Aphanizomenon) detected at the locations sampled.  
  • Microcystins exceeding the Warning Guidance for posting of planktonic blooms at Potato Point and exceeding the Caution Guidance at Tinsley Island and Lost Isle. (https://mywaterquality.ca.gov/habs/resources/habs_response.html#posting_guidance)  
      Microcystins (ug/L)  Recommended Signage  
Sample #  Site  Water Sample  Scum Sample  
11 San Joaquin River at Potato Point  10.56 Not collected Warning  
12 San Joaquin River at Tinsley Island 1.07 Not collected Caution 
13 San Joaquin River at Lost Isle 2.98 Not collected Caution 
14 Disappointment Slough ND Not collected  No Advisory 
15 Honker Cut ND Not collected   No Advisory 

Next Steps:   

Thank You, 

Matt Krause 

Environmental Scientist 

Region 5 Harmful Algal Bloom Coordinator 

California Regional Water Quality Control Board 

Central Valley Region (5) 

Surface Water Ambient Monitoring Program