Title 33 › Chapter CHAPTER 9— - PROTECTION OF NAVIGABLE WATERS AND OF HARBOR AND RIVER IMPROVEMENTS GENERALLY › Subchapter SUBCHAPTER I— - IN GENERAL › § 403a
It bans making any blockage in waters under U.S. control unless the law specifically allows it. Keeping such a blockage in place is also illegal, except for bridges, piers, docks, wharves, and similar business structures. Each week the blockage remains counts as a separate crime. People and companies who make or keep illegal blockages can be charged with a misdemeanor. They can be fined up to $5,000. A person (not a company) can also be jailed up to one year, or receive both jail and a fine. A federal district court can order the blockage stopped and removed, and the Attorney General can start those court actions.
Full Legal Text
Navigation and Navigable Waters — Source: USLM XML via OLRC
Legislative History
Reference
Citation
33 U.S.C. § 403a
Title 33 — Navigation and Navigable Waters
Last Updated
Apr 6, 2026
Release point: 119-73