[Scan-DC] Potomac Harbor Units Follow Up

[Thomas Philip Clouse]

Only MPD Harbor Branch and USCG have a regular law enforcement function in
D.C. waters.  Neither Park Police nor Border/Customs/ICE have any maritime
enforcement function in D.C. waters - the Anacostia and Potomac rivers from
Wilson Bridge to north of Georgetown.   Sounds like it was MPD Harbor
branch.  They do have a few different kind of boats, including small ones.
They operate on Citywide (Ch. 12) and 1D zones, as well as SOD.