5 U.S.C. § 5947 : US Code - Section 5947: Quarters, subsistence, and allowances for employees of the Corps of Engineers, Department of the Army, engaged in floating plant operations

      (a) An employee of the Corps of Engineers, Department of the
    Army, engaged in floating plant operations may be furnished
    quarters or subsistence, or both, on vessels, without charge, when
    the furnishing of the quarters or subsistence, or both, is
    determined to be equitable to the employee concerned, and necessary
    in the public interest, in connection with such operations.
      (b) Notwithstanding section 5536 of this title, an employee
    entitled to the benefits of subsection (a) of this section while on
    a vessel, may be paid, in place of these benefits, an allowance for
    quarters or subsistence, or both, when - 
        (1) adverse weather conditions or similar circumstances beyond
      the control of the employee or the Corps of Engineers prevent
      transportation of the employee from shore to the vessel; or
        (2) quarters or subsistence, or both, are not available on the
      vessel while it is undergoing repairs.

      (c) The quarters or subsistence, or both, or allowance in place
    thereof, may be furnished or paid only under regulations prescribed
    by the Secretary of the Army.