Water Quality Test Results

Ocean Monitoring

Humboldt County is funded by the U.S. Environmental Protection Agency Beach Environmental Assessment and Coastal Health Act (BEACH Act) to monitor for the presence of bacteria in ocean water areas. Water samples are taken near creek mouths that deliver stormwater into the ocean.

Current Results

No beaches are currently posted.

*Our beach sampling season ended October 31, 2019 and will resume in April 2020.*

Water quality test results by location and date.
Locations Resample Sample  Date 
E.Coli Exceeds
Enterococcus Exceeds
Clam Beach County Park No 10/29/2019 2,489 No 31 No 30 No
Luffenholtz Creek No 10/29/2019 754 No 10 No 20 No
Moonstone Beach No 10/29/2019 132 No 86 No 52 No
North Mad River Mouth No 10/29/2019 41 No <10 No <10 No
Trinidad State Park / Mill Creek No 10/29/2019 712 No <10 No <10 No

Previous results are available for download (XLS).


All units are in are in MPN/100 ml. MPN = "most probable number".

State water quality standards for bacteria in recreational waters are not to exceed:

  • Total coliform = 10,000 MPN/100ml*
  • E. coli (a fecal coliform) = 400 MPN/100 ml
  • Enterococcus (E. faecalis) = 104 MPN/100 ml

*Fecal coliform to total coliform ratio exceeds 0.1, and the total coliform count exceeds 1,000 MPN

NOWCAST Predictions

NOWCAST Predictive Modeling now includes Luffenholtz Beach. Visit beachreportcard.org and enter "Luffenholtz" into the "search for your favorite beach" form field.

For more information, visit beachreportcard.org.