409K's

What is POTUS possibly communicating here?

Removal of Water Obstruction!!! Watch the Water

https://www.law.cornell.edu/uscode/text/33/409

LII U.S. Code Title 33. NAVIGATION AND NAVIGABLE WATERS Chapter 9. PROTECTION OF NAVIGABLE WATERS AND OF HARBOR AND RIVER IMPROVEMENTS GENERALLY Subchapter I. IN GENERAL Section 409. Obstruction of navigable waters by vessels; floating timber; marking and removal of sunken vessels