---
kind: "section"
citation: "33 C.F.R. § 157.10a"
title: "33"
number: "157.10a"
heading: "Segregated ballast tanks, crude oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000 DWT or more."
url: "https://uscodex.org/cfr/33/157.10a"
---

# §157.10a. Segregated ballast tanks, crude oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000 DWT or more.

- (a) An existing vessel of 40,000 DWT or more that carries crude oil and a new vessel of 40,000 DWT or more but less than 70,000 DWT that carries crude oil must have:
  - (1) Segregated ballast tanks with a total capacity to meet the draft and trim requirements in [paragraph (d)](#d) of this section; or
  - (2) A crude oil washing system that meets the design, equipment, and installation requirements of subpart D of this part.
- (b) [Reserved]
- (c) An existing vessel of 40,000 DWT or more that carries products and a new vessel of 40,000 DWT or more but less than 70,000 DWT that carries products must have:
  - (1) Segregated ballast tanks with a total capacity to meet the draft and trim requirements in [paragraph (d)](#d) of this section; or
  - (2) Dedicated clean ballast tanks that have a total capacity to meet the draft and trim requirements in [paragraph (d)](#d) of this section and that meet the design and equipment requirements under [subpart E](/cfr/33/subpartE.md) of this part.
- (d) In any ballast condition during any part of a voyage, including that of lightweight with either segregated ballast in segregated ballast tanks or clean ballast in dedicated clean ballast tanks, each tank vessel under paragraph [(a)(1)](#a-1), or (c) of this section must have the capability of meeting each of the following without recourse to the use of cargo tanks for water ballast:
  - (1) The molded draft amidship (dm) in meters, without taking into account vessel deformation, must not be less than dm in the following mathematical relationship:
  - (2) The drafts at the forward and after perpendiculars must correspond to those determined by the draft amidship under [paragraph (d)(1)](#d-1) of this section, in association with a trim by the stern of no more than 0.015L.
  - (3) The minimum draft at the after perpendicular is that which is necessary to obtain full immersion of the propeller.
- (e) Each tank vessel that meets paragraph [(a)(1)](#a-1), or (c) of this section may be designed to carry ballast water in cargo tanks as allowed under [§ 157.35](/cfr/33/157.35.md).

## Notes

### Amendments

[CGD 77-058b, 45 FR 43707, June 30, 1980, as amended by CGD 82-28, 50 FR 11626, Mar. 22, 1985; USCG-1998-3799, 63 FR 35531, June 30, 1998]

### Authority

Authority: 33 U.S.C. 1903; 46 U.S.C. 3703, 3703a (note); Department of Homeland Security Delegation No. 0170.1. Subparts G, H, and I are also issued under section 4115(b), Pub. L. 101-380, 104 Stat. 520; Pub. L. 104-55, 109 Stat. 546.

### Source

Source: CGD 74-32, 40 FR 48283, Oct. 14, 1975, unless otherwise noted.

### Amendments

[CGD 77-058b, 45 FR 43707, June 30, 1980, as amended by CGD 82-28, 50 FR 11626, Mar. 22, 1985; USCG-1998-3799, 63 FR 35531, June 30, 1998]