part_subject: "NATIONAL PRIMARY DRINKING WATER REGULATIONS"
subpart_code: "B"
subpart_subject: "Maximum Contaminant Levels"
section_number: "141.13"
section_subject: "Maximum contaminant levels for turbidity."
cfr_reference: "40 CFR 141.13"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 136 to 149"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
---
The maximum contaminant levels for turbidity are applicable to both community water systems and non-community water systems using surface water sources in whole or in part. The maximum contaminant levels for turbidity in drinking water, measured at a representative entry point(s) to the distribution system, are:
(a)One turbidity unit (TU), as determined by a monthly average pursuant to § 141.22, except that five or fewer turbidity units may be allowed if the supplier of water can demonstrate to the State that the higher turbidity does not do any of the following:
(b)Five turbidity units based on an average for two consecutive days pursuant to § 141.22.
At 54 FR 27527, June 29, 1989, § 141.13 was amended by adding introductory text; however, the amendment could not be incorporated because introductory text already exists.