California Water Quality Directory
Find detailed information about water quality in cities and ZIP codes across California. Discover which contaminants might be present and understand how they compare to EPA and recommended limits.
Cities starting with "H"
Hacienda Heights
Half Moon Bay
Hamilton City
Hanford
Happy Camp
Harbor City
Hat Creek
Hathaway Pines
Hawaiian Gardens
Hawthorne
Hayfork
Hayward
Healdsburg
Heber
Helendale
Helm
Hemet
Herald
Hercules
Herlong
Hermosa Beach
Hesperia
Hickman
Hidden Valley Lake
Highland
Hilmar
Hinkley
Hollister
Holtville
Homeland
Homewood
Honeydew
Hood
Hoopa
Hopland
Hornbrook
Hornitos
Hughson
Hume
Huntington Beach
Huntington Park
Huron
Hyampom
Hydesville
About Water Quality
Water quality is a measure of the suitability of water for a particular use based on selected physical, chemical, and biological characteristics. In California, water quality can vary significantly by location, affected by factors such as:
Understanding Contaminants
Water contaminants include a wide range of substances from natural minerals to industrial chemicals. Some have health implications, while others affect taste, odor, or appearance of water.
EPA Standards
The Environmental Protection Agency (EPA) sets legal limits for contaminants in drinking water. These standards protect public health by limiting the levels of contaminants allowed.
Health Guidelines
Beyond EPA limits, there are often stricter health-based guidelines recommended by scientists and health organizations for optimal water quality.
Common Contaminants
Common water contaminants in California include arsenic, lead, nitrates, bacteria, pesticides, and industrial chemicals that can vary by region.