Conn. Gen. Stat. § 19a-37k
The owner of any residential or commercial property shall notify each tenant of any leased or rented unit located on such property and the lessee of such property whenever any testing of the water supply for such property indicates that the water exceeds a maximum contaminant level applicable to water supply systems for any contaminant listed in the regulations of Connecticut state agencies or for any contaminant listed on the state drinking water action level list established pursuant to section 22a-471. As soon as practicable, but not later than forty-eight hours after receiving notification of the results of such testing, the owner shall forward a copy of such notification to each such tenant and lessee. The local director of health shall take all reasonable steps to verify that such owner forwarded the notice required pursuant to this section.
Conn. Gen. Stat. § 19a-37k