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 (PDF) that deliver stormwater into the ocean.

Current Results

The following beach is posted: Clam Beach/Strawberry Creek
Water quality test results by location and date.
Locations Resample Sample  Data 
E.Coli Exceeds
Enterococcus Exceeds
Clam Beach County Park Yes 8/16/2017 4,106 No 109 No 146 Yes
Trinidad State Park / Mill Creek Yes 8/16/2017
1,137 No 52 No 63 No
Clam Beach County Park No 8/14/2017 3,654 No 84 No 135 Yes
Luffenholtz Creek No 8/14/2017 3,873
No 20 No 20 No
Moonstone Beach No 8/14/2017 1,956
No 63
No 10 No
North Mad River Mouth No 8/14/2017 1,314 No <10 No
<10 No
Trinidad State Park / Mill Creek No 8/14/2017 2,613 No 63 No 171 Yes
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