40 CFR § 131.13 - General policies.

---
identifier: "/us/cfr/t40/s131.13"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 131.13 - General policies."
title_number: 40
title_name: "Protection of Environment"
section_number: "131.13"
section_name: "General policies."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "D"
subchapter_name: "WATER PROGRAMS"
part_number: "131"
part_name: "WATER QUALITY STANDARDS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "33 U.S.C. 1251"
regulatory_source: "48 FR 51405, Nov. 8, 1983, unless otherwise noted."
cfr_part: "131"
---


# 131.13 General policies.

States may, at their discretion, include in their State standards, policies generally affecting their application and implementation, such as mixing zones, low flows and variances. Such policies are subject to EPA review and approval.