The Coast Guard can now block boats on the Potomac for a funeral

The Coast Guard will enforce a temporary security zone on the Potomac and Anacostia Rivers in Washington, DC. This means boats cannot enter or stay in certain areas without permission during a state funeral.

This is a routine, temporary measure for a specific event. It shows how quickly and broadly federal agencies can restrict public access to waterways when they declare a security need. The authority to do this is always present, but it is rarely exercised so broadly for a non-military event.