46 CFR 140.725: Additional navigation equipment on towing vessels

Last reviewed: October 14, 2026

This section lists extra navigation equipment that towing vessels must carry, as applicable to the area of operation. The list covers a fathometer, a search light, an electronic position-fixing device and an illuminated compass or swing-meter. A note points to 33 CFR 164.72 and 33 CFR 164.46 for some vessels.

Applies toTowing vessels, with each item required as applicable to the area of operation.

What it says

  1. Towing vessels must carry the listed equipment, as applicable to the area of operation.

    “Towing vessels must be equipped with the following equipment, as applicable to the area of operation:”

  2. Towing vessels must have a fathometer, except on Western Rivers.

    46 CFR 140.725(a)“Fathometer (except Western Rivers).”

  3. Towing vessels must have a search light that is controllable from the vessel's operating station and can illuminate objects at a distance of at least two times the length of the tow.

    46 CFR 140.725(b)“Search light, controllable from the vessel's operating station and capable of illuminating objects at a distance of at least two times the length of the tow.”

  4. A towing vessel must have an electronic position-fixing device, satisfactory for the area in which it operates, if it tows seaward of the navigable waters of the U.S. or more than 3 nautical miles from shore on the Great Lakes.

    46 CFR 140.725(c)“Electronic position-fixing device, satisfactory for the area in which the vessel operates, if the towing vessel engages in towing seaward of the navigable waters of the U.S. or more than 3 nautical miles from shore on the Great Lakes.”

  5. Western Rivers vessels only must have an illuminated magnetic compass or an illuminated swing-meter.

    46 CFR 140.725(d)“Illuminated magnetic compass or an illuminated swing-meter (Western Rivers vessels only).”

  6. The compass or swing-meter must be readable from each operating station.

    46 CFR 140.725(d)“The compass or swing-meter must be readable from each operating station.”

Common questions

Does a towing vessel on the Western Rivers need a fathometer?

No. The fathometer requirement excepts Western Rivers.

“Fathometer (except Western Rivers).”

When does a towing vessel need an electronic position-fixing device?

It needs one if it tows seaward of the navigable waters of the U.S. or more than 3 nautical miles from shore on the Great Lakes. The device must be satisfactory for the area in which the vessel operates.

“Electronic position-fixing device, satisfactory for the area in which the vessel operates, if the towing vessel engages in towing seaward of the navigable waters of the U.S. or more than 3 nautical miles from shore on the Great Lakes.”

How far must a towing vessel's search light reach?

It must be capable of illuminating objects at a distance of at least two times the length of the tow. It must also be controllable from the vessel's operating station.

“Search light, controllable from the vessel's operating station and capable of illuminating objects at a distance of at least two times the length of the tow.”

Are other navigation requirements possible for towing vessels under this section?

Yes. The note says certain towing vessels subject to this section are also subject to 33 CFR 164.72 and the Automatic Identification System requirements of 33 CFR 164.46.

“Certain towing vessels subject to § 140.725 are also subject to the requirements of 33 CFR 164.72 and Automatic Identification System requirements of 33 CFR 164.46.”

The text of 46 CFR 140.725

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Additional navigation equipment

Towing vessels must be equipped with the following equipment, as applicable to the area of operation:

(a) Fathometer (except Western Rivers).

(b) Search light, controllable from the vessel's operating station and capable of illuminating objects at a distance of at least two times the length of the tow.

(c) Electronic position-fixing device, satisfactory for the area in which the vessel operates, if the towing vessel engages in towing seaward of the navigable waters of the U.S. or more than 3 nautical miles from shore on the Great Lakes.

(d) Illuminated magnetic compass or an illuminated swing-meter (Western Rivers vessels only). The compass or swing-meter must be readable from each operating station.

Note to § 140.725. Certain towing vessels subject to § 140.725 are also subject to the requirements of 33 CFR 164.72 and Automatic Identification System requirements of 33 CFR 164.46.

Sections it refers to

The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.