Cuore Hard Water Index

A first-party index built only from verified Cuore water measurements.

The Cuore Hard Water Index is intended to compare observed water-hardness conditions across locations using Cuore's own documented samples. It is a research and consumer-information index, not a drinking-water safety rating or regulatory compliance score.

Index design

The index will use verified measurements of total hardness, expressed as mg/L as CaCO3, with the underlying sample record available for methodological review. TDS will be reported separately and will not be used as a substitute for hardness.

When a location can receive an index

A location will only receive a published index value after Cuore has enough documented samples to support a location-level summary. Until that threshold is met, the location will remain unranked.

How locations will be compared

Cuore will report the observed distribution of verified hardness values and the location's position within the Cuore dataset. The index will be updated as the dataset grows, with the measurement period and sample count stated alongside published results.

Important limitations

• Water quality can vary by source, supply network, building and time.
• A city-level index cannot determine the hardness of an individual household's water.
• The index does not establish that hard water causes a particular medical or cosmetic outcome.

Current status

Index framework established; rankings pending verified first-party measurements.

Explore Cuore Water Intelligence for the underlying data framework.