Thomas, J., concurring
Stat. 1151 (codified, as amended, at 33 U. S. C. §403). In addition, §13 of the Act, sometimes referred to as the “Refuse Act,” prohibits throwing, discharging, or depositing “any refuse matter … into any navigable water of the United States, or into any tributary of any navigable water from which the same shall float or be washed into such navigable water.” 30 Stat. 1152 (codified, as amended, at 33 U. S. C. §407). Section 13 also prohibits depositing material “on the bank of any navigable water, or on the bank of any tributary of any navigable water, where the same shall be liable to be washed into such navigable water … whereby navigation shall or may be impeded or obstructed.” Ibid.
Three things stand out about these provisions. First, they use the terms “navigable water,” “water of the United States,” and “navigable water of the United States” interchangeably. 33 U. S. C. §§403 and 407; see also V. Albrecht & S. Nickelsburg, Could SWANCC Be Right? A New Look at the Legislative History of the Clean Water Act, 32 Env. L. Rev. 11042, 11044 (2002) (Albrecht & Nickelsburg). As a result, courts have done the same in decisions interpreting the River and Harbor Acts. See, e.g., United States v. Stoeco Homes, Inc., 498 F. 2d 597, 608–609 (CA3 1974); New England Dredging Co. v. United States, 144 F. 932, 933–934 (CA1 1906); Blake v. United States, 181 F. Supp. 584, 587–588 (ED Va. 1960).
Second, Congress asserted its authority only to the extent that obstructions or refuse matter could impede navigation or navigable capacity. Thus, in United States v. Rio Grande Dam & Irrigation Co., 174 U. S. 690 (1899), this Court recognized that any “act sought to be enjoined” under the 1890 Act must be “one which fairly and directly tends to obstruct (that is, interfere with or diminish) the navigable capacity of a stream.” Id., at 709; accord, Lake Shore & Michigan Southern R. Co. v. Ohio, 165 U. S. 365, 369 (1897) (holding
