This subpart applies to each self-propelled hopper dredge—

(a) For which a working freeboard assignment is desired after January 1, 1990; and

(b) That operates with a working freeboard assigned under this subpart.

Hopper dredge means a self-propelled dredge with an open hold or hopper in the hull of the dredge that receives dredged material.

Working freeboard means one-half the distance between the mark of the load line assigned under this subchapter and the freeboard deck.

To request a working freeboard, calculations, plans, and stability information necessary to demonstrate compliance with this subpart must be submitted to the:

(a) Commanding Officer, Marine Safety Center, U.S. Coast Guard, 2703 Martin Luther King Jr. Avenue SE., Washington, DC 20593, for visitors. Send all mail to Commanding Officer (MSC), Attn: Marine Safety Center, U.S. Coast Guard Stop 7430, 2703 Martin Luther King Jr. Avenue SE., Washington, DC 20593-7430; or

(b) American Bureau of Shipping, ABS Plaza, 16855 Northchase Drive, Houston, TX 77060.

[CGD 76-080, 54 FR 36977, Sept. 6, 1989, as amended by USCG-1998-4442, 63 FR 52190, Sept. 30, 1998; USCG-2000-7790, 65 FR 58459, Sept. 29, 2000; USCG-2007-29018, 72 FR 53965, Sept. 21, 2007; USCG-2009-0702, 74 FR 49228, Sept. 25, 2009; USCG-2013-0671, 78 FR 60147, Sept. 30, 2013; USCG-2016-0498, 82 FR 35089, July 28, 2017]

A hopper dredge may be issued a working freeboard on a limited service domestic voyage load line certificate or a Great Lakes load line certificate if the following are met:

(a) The hopper dredge structure must have adequate strength for any draft up to the working freeboard draft. Dredges built and maintained in conformity with the requirements of a classification society recognized by the Commandant usually meet this requirement.

(b) The hopper dredge must—

(1) Meet subpart I of part 174 of this chapter; and

(2) Have on its bridge remote draft indicators that:

(i) Show the fore, aft, and mean draft of the dredge at all times while the dredge is operating; and

(ii) Have each indicator marked with the assigned freeboard and the working freeboard.

(a) Each hopper dredge assigned a working freeboard may be operated at drafts from the normal freeboard to the working freeboard if the—

(1) Seas are not more than 10 feet;

(2) Winds are not more than 35 knots;

(3) Area of operation is not more than 20 nautical miles (37 kilometers) from the mouth of a harbor of safe refuge; and

(4) Specific gravity of the spoil carried is not more than the highest specific gravity of spoil used in the stability calculations required by subchapter S of this chapter.

(b) The Assigning Authority designates on the face of the dredge's load line certificate—

(1) Each restriction contained in paragraph (a)(1) through (a)(3) of this section; and

(2) The maximum specific gravity of the spoils allowed to be carried.