Water Authorities - As introduced, establishes that public water systems have a maximum allowable hardwater level of 180 mg/L, measured as calcium carbonate equivalents; creates compliance and reporting requirements; exempts measurements that exceed the limit due to seasonal runoff in certain circumstances. - Amends TCA Title 68, Chapter 221, Part 7.

SB 1962 sets a maximum hardwater level of 180 mg/L (measured as calcium carbonate) for public water systems in Tennessee. It requires systems receiving state funds for major upgrades (costing $25,000+) after July 1, 2026, to comply with this standard upon completion. Systems not using state funds for such upgrades are exempt until they later qualify for state-funded projects. Temporary exemptions for seasonal runoff (like snowmelt) are allowed with documentation and a 90-day return-to-compliance deadline, but cannot exceed 120 days yearly without department approval. All affected systems must monitor and report hardwater levels as part of annual water quality reports.