Report terms

CCR: Consumer Confidence Report, an annual drinking-water report from many public water systems.

MCL: Maximum Contaminant Level, an enforceable regulatory limit for certain contaminants.

ppm / ppb: Parts per million or parts per billion, common units in water reports.

Hardness terms

Hardness: A measure of dissolved minerals, mainly calcium and magnesium.

gpg: Grains per gallon, often used for softener sizing.

mg/L as CaCO3: A common way to report hardness as calcium carbonate.

System terms

provider ID: Public Water System Identifier.

Community water system: A public water system serving the same people year-round.

Provider matching: Identifying which utility or water system likely serves a location.

Treatment terms

Water softener: Equipment designed to reduce hardness minerals.

Carbon filter: A filter type often used for taste, odor, and some certified contaminant-reduction goals.

Reverse osmosis: A treatment method that can reduce certain dissolved substances depending on system design and certification.