---
kind: "section"
citation: "16 U.S.C. § 817"
title: "16"
title_heading: "Conservation"
number: "817"
heading: "Projects not affecting navigable waters; necessity for Federal license, permit or right-of-way; unauthorized activities"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/16/817"
units:
  - "Chapter 12 — Federal Regulation and Development of Power"
  - "Subchapter I — Regulation of the Development of Water Power and Resources"
---

# §817. Projects not affecting navigable waters; necessity for Federal license, permit or right-of-way; unauthorized activities

- (1) It shall be unlawful for any [person](/usc/16/796.md?p=4), [State](/usc/16/796.md?p=6), or [municipality](/usc/16/796.md?p=7), for the purpose of developing electric power, to construct, operate, or maintain any dam, water conduit, reservoir, power house, or other works incidental thereto across, along, or in any of the [navigable waters](/usc/16/796.md?p=8) of the United States, or upon any part of the [public lands](/usc/16/796.md?p=1) or [reservations](/usc/16/796.md?p=2) of the United States (including the Territories), or utilize the surplus water or water power from any [Government dam](/usc/16/796.md?p=10), except under and in accordance with the terms of a permit or valid existing right-of-way granted prior to June 10, 1920, or a license granted pursuant to this chapter. Any [person](/usc/16/796.md?p=4), association, [corporation](/usc/16/796.md?p=3), [State](/usc/16/796.md?p=6), or [municipality](/usc/16/796.md?p=7) intending to construct a dam or other [project works](/usc/16/796.md?p=12), across, along, over, or in any stream or part thereof, other than those defined in this chapter as [navigable waters](/usc/16/796.md?p=8), and over which Congress has jurisdiction under its authority to regulate commerce with foreign nations and among the several [States](/usc/16/544.md?p=r) shall before such construction file declaration of such intention with the [Commission](/usc/16/544.md?p=c), whereupon the [Commission](/usc/16/544.md?p=c) shall cause immediate investigation of such proposed construction to be made, and if upon investigation it shall find that the interests of interstate or foreign commerce would be affected by such proposed construction, such [person](/usc/16/796.md?p=4), association, [corporation](/usc/16/796.md?p=3), [State](/usc/16/796.md?p=6), or [municipality](/usc/16/796.md?p=7) shall not construct, maintain, or operate such dam or other [project works](/usc/16/796.md?p=12) until it shall have applied for and shall have received a license under the provisions of this chapter. If the [Commission](/usc/16/544.md?p=c) shall not so find, and if no [public lands](/usc/16/796.md?p=1) or [reservations](/usc/16/796.md?p=2) are affected, permission is granted to construct such dam or other [project works](/usc/16/796.md?p=12) in such stream upon compliance with [State](/usc/16/796.md?p=6) laws.
- (2) No [person](/usc/16/796.md?p=4) may commence any significant modification of any [project](/usc/16/796.md?p=11) licensed under, or exempted from, this chapter unless such modification is authorized in accordance with terms and conditions of such license or exemption and the applicable requirements of this subchapter. As used in this paragraph, the term “commence” refers to the beginning of physical on-site activity other than surveys or testing.

## Source credit

(June 10, 1920, ch. 285, pt. I, § 23(b), 41 Stat. 1075; renumbered pt. I and amended, Aug. 26, 1935, ch. 687, title II, §§ 210, 212, 49 Stat. 846, 847; Pub. L. 99–495, § 6, Oct. 16, 1986, 100 Stat. 1248.)

## Notes

### Editorial Notes

### Codification

Section consists of subsec. (b) of section 23 of act June 10, 1920, as so designated by act Aug. 26, 1935. Subsec. (a) of section 23 of act June 10, 1920, is set out as section 816 of this title.

### Amendments

1986—Pub. L. 99–495 designated existing provisions as par. (1) and added par. (2).

1935—Act Aug. 26, 1935, § 210, amended section generally, inserting first sentence, and substituting “with foreign nations” for “between foreign nations”, “shall before such construction” for “may in their discretion” and “shall not construct, maintain, or operate such dam or other project works” for “shall not proceed with such construction”.

### Statutory Notes and Related Subsidiaries

### Effective Date of 1986 Amendment

Amendment by Pub. L. 99–495 applicable to licenses, permits, and exemptions without regard to when issued, see section 18 of Pub. L. 99–495, set out as a note under section 797 of this title.