SCOWS
| Date | Clue |
|---|---|
| 2019-04-14 | Junk transporters |
| 2018-08-02 | Trash boats |
| 2017-05-08 | Garbage-carrying boats |
| 2016-05-17 | Garbage transporters |
| 2014-06-09 | Garbage boats |
| 2010-11-05 | Junk vehicles |
| 2009-10-29 | Punts, e.g. |
| 2008-05-15 | Barges |
| 2008-04-03 | Barges |
| 2002-06-29 | Tugs' tows |
| 1999-06-20 | Some coal carriers |
| 1998-07-26 | Garbage haulers |
| 1994-10-01 | Harbor haulers |